Airend Condition, Performance Degradation & Overhaul Decision Engineering

AIREND CONDITION, PERFORMANCE DEGRADATION & OVERHAUL DECISION ENGINEERING

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Provisional new-series slug: /compressed-air-engineering/airend-condition-performance-degradation-overhaul-decision/ | CTA: Review My Airend Condition

Do not overhaul an airend because it has hours. overhaul it when the evidence shows that restoring internal condition is the right lifecycle decision

It prevents capacity, temperature, vibration or energy symptoms from being assigned to the airend before package and system causes are tested.

Capacity loss may arise from intake restriction, controls, leakage, separator restriction, cooling, speed/load state or measurement error. High temperature may arise from cooling or fluid problems. Vibration may arise from motor, coupling, foundation or piping. An overhaul decision therefore follows a controlled diagnostic chain and exact airend identification.

1 — Airend Identity

Airend Decision Foundation: govern airend identity using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

2 — Compressor Identity

Airend Decision Foundation: govern compressor identity using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

3 — Airend Technology

Airend Decision Foundation: govern airend technology using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

4 — Drive Arrangement

Airend Decision Foundation: govern drive arrangement using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

5 — Lubrication Architecture

Airend Decision Foundation: govern lubrication architecture using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

6 — Operating Hours

Airend Decision Foundation: govern operating hours using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

7 — Load Hours

Airend Decision Foundation: govern load hours using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

8 — Starts/Cycles

Airend Decision Foundation: govern starts/cycles using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

9 — Pressure History

Airend Decision Foundation: govern pressure history using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

10 — Ambient History

Airend Decision Foundation: govern ambient history using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

11 — Maintenance History

Airend Decision Foundation: govern maintenance history using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

12 — Overhaul History

Airend Decision Foundation: govern overhaul history using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

13 — Failure History

Airend Decision Foundation: govern failure history using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

14 — Current Symptoms

Airend Decision Foundation: govern current symptoms using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

15 — Decision Owner

Airend Decision Foundation: govern decision owner using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

16 — Required Fad

Functional Performance: govern required FAD using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

17 — Measured Fad

Functional Performance: govern measured FAD using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

18 — Required Pressure

Functional Performance: govern required pressure using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

19 — Delivered Pressure

Functional Performance: govern delivered pressure using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

20 — Specific Power

Functional Performance: govern specific power using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

21 — Input Power

Functional Performance: govern input power using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

22 — Speed/Load Relationship

Functional Performance: govern speed/load relationship using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

23 — Loaded Temperature

Functional Performance: govern loaded temperature using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

24 — Unloaded Behaviour

Functional Performance: govern unloaded behaviour using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

25 — Load/Unload Cycling

Functional Performance: govern load/unload cycling using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

26 — Vsd Envelope

Functional Performance: govern VSD envelope using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

27 — Oil-Carryover Context

Functional Performance: govern oil-carryover context using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

28 — Noise Condition

Functional Performance: govern noise condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

29 — Vibration Condition

Functional Performance: govern vibration condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

30 — Accepted Baseline

Functional Performance: govern accepted baseline using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

31 — Intake Restriction

Degradation Screening: govern intake restriction using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

32 — Air-Filter Condition

Degradation Screening: govern air-filter condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

33 — Inlet-Valve Function

Degradation Screening: govern inlet-valve function using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

34 — Separator Restriction

Degradation Screening: govern separator restriction using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

35 — Oil-Filter Restriction

Degradation Screening: govern oil-filter restriction using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

36 — Cooler Condition

Degradation Screening: govern cooler condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

37 — Lubricant Condition

Degradation Screening: govern lubricant condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

38 — Thermostatic/Bypass Condition

Degradation Screening: govern thermostatic/bypass condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

39 — Minimum-Pressure Valve

Degradation Screening: govern minimum-pressure valve using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

40 — Blowdown System

Degradation Screening: govern blowdown system using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

41 — Internal Leakage Suspicion

Degradation Screening: govern internal leakage suspicion using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

42 — External Leakage

Degradation Screening: govern external leakage using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

43 — Controls/Setpoint Issue

Degradation Screening: govern controls/setpoint issue using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

44 — Sensor Accuracy

Degradation Screening: govern sensor accuracy using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

45 — Measurement Uncertainty

Degradation Screening: govern measurement uncertainty using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

46 — Airend Vibration

Mechanical Condition: govern airend vibration using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

47 — Bearing Vibration

Mechanical Condition: govern bearing vibration using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

48 — Bearing Temperature

Mechanical Condition: govern bearing temperature using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

49 — Rotor-Contact Suspicion

Mechanical Condition: govern rotor-contact suspicion using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

50 — Gear Condition

Mechanical Condition: govern gear condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

51 — Coupling Condition

Mechanical Condition: govern coupling condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

52 — Shaft Condition

Mechanical Condition: govern shaft condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

53 — Seal Condition

Mechanical Condition: govern seal condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

54 — Lubrication Evidence

Mechanical Condition: govern lubrication evidence using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

55 — Wear Debris

Mechanical Condition: govern wear debris using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

56 — Abnormal Noise

Mechanical Condition: govern abnormal noise using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

57 — End-Float Boundary

Mechanical Condition: govern end-float boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

58 — Alignment Context

Mechanical Condition: govern alignment context using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

59 — Foundation/Piping Influence

Mechanical Condition: govern foundation/piping influence using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

60 — Specialist Review

Mechanical Condition: govern specialist review using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

61 — Capacity Decline

Performance Degradation: govern capacity decline using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

62 — Specific-Power Increase

Performance Degradation: govern specific-power increase using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

63 — Temperature Increase

Performance Degradation: govern temperature increase using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

64 — Pressure Instability

Performance Degradation: govern pressure instability using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

65 — Unloaded-Power Increase

Performance Degradation: govern unloaded-power increase using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

66 — Cycling Increase

Performance Degradation: govern cycling increase using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

67 — Separator-Dp Increase

Performance Degradation: govern separator-DP increase using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

68 — Intake-Dp Increase

Performance Degradation: govern intake-DP increase using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

69 — Cooler-Approach Increase

Performance Degradation: govern cooler-approach increase using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

70 — Oil-Consumption Change

Performance Degradation: govern oil-consumption change using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

71 — Carryover Change

Performance Degradation: govern carryover change using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

72 — Vibration Trend

Performance Degradation: govern vibration trend using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

73 — Noise Trend

Performance Degradation: govern noise trend using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

74 — Alarm Frequency

Performance Degradation: govern alarm frequency using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

75 — Degradation Rate

Performance Degradation: govern degradation rate using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

76 — External Inspection

Inspection & Evidence: govern external inspection using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

77 — Borescope Boundary

Inspection & Evidence: govern borescope boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

78 — Oil Analysis

Inspection & Evidence: govern oil analysis using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

79 — Vibration Analysis

Inspection & Evidence: govern vibration analysis using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

80 — Thermal Analysis

Inspection & Evidence: govern thermal analysis using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

81 — Performance Test

Inspection & Evidence: govern performance test using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

82 — Leak Test

Inspection & Evidence: govern leak test using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

83 — Control Review

Inspection & Evidence: govern control review using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

84 — Service Records

Inspection & Evidence: govern service records using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

85 — Parts History

Inspection & Evidence: govern parts history using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

86 — Failure Debris

Inspection & Evidence: govern failure debris using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

87 — Filter/Separator Evidence

Inspection & Evidence: govern filter/separator evidence using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

88 — Cooler Evidence

Inspection & Evidence: govern cooler evidence using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

89 — Photographic Evidence

Inspection & Evidence: govern photographic evidence using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

90 — Measurement Traceability

Inspection & Evidence: govern measurement traceability using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

91 — Bearing Replacement Boundary

Overhaul Scope: govern bearing replacement boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

92 — Seal Replacement Boundary

Overhaul Scope: govern seal replacement boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

93 — Gasket/O-Ring Boundary

Overhaul Scope: govern gasket/O-ring boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

94 — Rotor Inspection

Overhaul Scope: govern rotor inspection using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

95 — Housing Inspection

Overhaul Scope: govern housing inspection using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

96 — Shaft Inspection

Overhaul Scope: govern shaft inspection using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

97 — Gear Inspection

Overhaul Scope: govern gear inspection using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

98 — Clearance Measurement

Overhaul Scope: govern clearance measurement using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

99 — Surface-Condition Review

Overhaul Scope: govern surface-condition review using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

100 — Cleaning Process

Overhaul Scope: govern cleaning process using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

101 — Parts Traceability

Overhaul Scope: govern parts traceability using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

102 — Assembly Cleanliness

Overhaul Scope: govern assembly cleanliness using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

103 — Special Tools

Overhaul Scope: govern special tools using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

104 — Metrology Requirement

Overhaul Scope: govern metrology requirement using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

105 — Scope Deviation Control

Overhaul Scope: govern scope deviation control using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

106 — Rotor-To-Rotor Clearance Boundary

Internal Condition: govern rotor-to-rotor clearance boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

107 — Rotor-To-Housing Clearance Boundary

Internal Condition: govern rotor-to-housing clearance boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

108 — End-Clearance Boundary

Internal Condition: govern end-clearance boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

109 — Bearing-Fit Boundary

Internal Condition: govern bearing-fit boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

110 — Shaft-Fit Boundary

Internal Condition: govern shaft-fit boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

111 — Gear-Backlash Boundary

Internal Condition: govern gear-backlash boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

112 — Preload Boundary

Internal Condition: govern preload boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

113 — Seal Running Surface

Internal Condition: govern seal running surface using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

114 — Housing Condition

Internal Condition: govern housing condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

115 — Rotor Coating Boundary

Internal Condition: govern rotor coating boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

116 — Corrosion/Erosion

Internal Condition: govern corrosion/erosion using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

117 — Scoring/Rubbing

Internal Condition: govern scoring/rubbing using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

118 — Deposit Formation

Internal Condition: govern deposit formation using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

119 — Measurement-Temperature Context

Internal Condition: govern measurement-temperature context using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

120 — Oem Data Requirement

Internal Condition: govern OEM data requirement using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

121 — Repairability

Overhaul vs Replacement: govern repairability using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

122 — Parts Availability

Overhaul vs Replacement: govern parts availability using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

123 — Airend Age

Overhaul vs Replacement: govern airend age using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

124 — Repeat-Failure History

Overhaul vs Replacement: govern repeat-failure history using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

125 — Housing/Rotor Condition

Overhaul vs Replacement: govern housing/rotor condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

126 — Bearing-Seat Condition

Overhaul vs Replacement: govern bearing-seat condition using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

127 — Obsolete Design

Overhaul vs Replacement: govern obsolete design using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

128 — Replacement-Airend Availability

Overhaul vs Replacement: govern replacement-airend availability using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

129 — New-Compressor Alternative

Overhaul vs Replacement: govern new-compressor alternative using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

130 — Energy-Performance Gap

Overhaul vs Replacement: govern energy-performance gap using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

131 — Future Capacity Need

Overhaul vs Replacement: govern future capacity need using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

132 — Future Pressure Need

Overhaul vs Replacement: govern future pressure need using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

133 — Downtime Exposure

Overhaul vs Replacement: govern downtime exposure using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

134 — Warranty/Support Boundary

Overhaul vs Replacement: govern warranty/support boundary using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

135 — Lifecycle Economics

Overhaul vs Replacement: govern lifecycle economics using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

136 — Assembly Verification

Post-Rebuild Validation: govern assembly verification using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

137 — Rotation/Free-Movement Check

Post-Rebuild Validation: govern rotation/free-movement check using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

138 — Lubrication Readiness

Post-Rebuild Validation: govern lubrication readiness using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

139 — Leak Check

Post-Rebuild Validation: govern leak check using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

140 — Initial Start

Post-Rebuild Validation: govern initial start using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

141 — Temperature Stabilisation

Post-Rebuild Validation: govern temperature stabilisation using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

142 — Vibration Baseline

Post-Rebuild Validation: govern vibration baseline using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

143 — Noise Baseline

Post-Rebuild Validation: govern noise baseline using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

144 — Pressure Control

Post-Rebuild Validation: govern pressure control using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

145 — Capacity Verification

Post-Rebuild Validation: govern capacity verification using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

146 — Power Verification

Post-Rebuild Validation: govern power verification using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

147 — Specific-Power Comparison

Post-Rebuild Validation: govern specific-power comparison using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

148 — Carryover Observation

Post-Rebuild Validation: govern carryover observation using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

149 — Alarm/Trip Review

Post-Rebuild Validation: govern alarm/trip review using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

150 — Handover Baseline

Post-Rebuild Validation: govern handover baseline using exact compressor and airend make/model/serial, operating history, configuration, measured performance and condition evidence. Separate confirmed defects from symptoms and assumptions. Exact bearings, seals, fits, preload, internal clearances, torque values, rotor geometry and acceptance limits must come from current manufacturer/specialist data for the identified airend. Preserve as-found evidence before cleaning/disassembly removes it and verify the as-left state after intervention.

151 — Premium Airend Condition & Decision Register

152 — Overhaul Decision Matrix

153 — Diagnostic Separation: Airend or System?

Confirm flow measurement boundary before declaring capacity loss.

Confirm discharge pressure and representative load.

Check intake restriction and inlet-valve behaviour.

Check separator DP and minimum-pressure valve.

Check cooler, ventilation and fluid condition before blaming high temperature.

Check external leakage and demand changes.

Check controller, sensors, VSD and sequencing.

Check motor/drive/coupling before attributing vibration to airend.

Correlate oil wear evidence with vibration and inspection.

Compare against accepted baseline/reference.

Account for ambient/altitude where relevant.

Do not use one symptom as proof of internal failure.

Escalate to specialist inspection when evidence justifies it.

Preserve uncertainty when measurements are incomplete.

Avoid unnecessary dismantling solely to obtain evidence.

154 — Overhaul Work-Pack Architecture

Exact airend/compressor identification.

Reason for removal and symptoms.

Pre-removal performance/condition evidence.

Isolation, lifting and handling plan.

Cleanliness controls.

As-found photographs.

Authorised as-found measurements.

Traceable parts list.

Inspection disposition for rotors/housing/shafts/gears/bearings/seals.

Specialist repair/acceptance evidence.

Controlled assembly and cleanliness.

Exact OEM/specialist assembly data.

Deviation/nonconformance record.

Reinstallation/alignment checks.

Post-rebuild commissioning and baseline.

155 — Failure-Mechanism Review

Lubrication starvation or unsuitable lubricant.

Contamination ingress or poor cleanliness.

Overtemperature / thermal stress.

Water/moisture contamination.

Operation outside approved pressure envelope.

Misalignment/drive influence.

Foundation or piping loads.

Bearing deterioration.

Seal degradation.

Gear deterioration where applicable.

Rotor contact/scoring/coating damage.

Corrosion/erosion/process contamination.

Foreign-object damage.

Maintenance-induced assembly error.

Unresolved root cause from earlier failure.

156 — Lifecycle Economics & Decision Logic

Compare more than repair price: restored performance, parts/support availability, downtime, energy performance, repeat-failure risk, remaining package condition, controls obsolescence, future demand and temporary-air or lost-production exposure.

A repairable airend may still be the wrong investment if the package is obsolete, inefficient for the duty or unsupported. Conversely, a newer compressor should not be replaced merely because an airend bearing requires a technically supportable overhaul. State assumptions and compare overhaul, replacement airend, verified exchange/remanufactured options, complete compressor replacement or system redesign on a defined horizon.

157 — Technical / Airend Verification Gate

Exact compressor/airend identity verified

Symptoms separated from confirmed failure modes

External causes screened

Flow/power/pressure boundaries controlled

Vibration/oil/thermal evidence correlated

Internal dimensions/assembly data model-specific

No generic bearing/seal/clearance/preload/torque published

As-found condition preserved

Parts applicability/traceability controlled

Repair processes preserve geometry/integrity

Repeat failure triggers RCA

Economics include downtime/future duty/obsolescence

Post-rebuild validation establishes new baseline

Specialist rebuild capability claims evidence-gated

When does an airend need overhaul?

When model-specific condition/performance evidence shows internal degradation best corrected by specialist rebuild—not merely because a generic hour threshold is reached.

Does low capacity mean worn airend?

Not automatically. Intake, controls, speed, leakage, separator restriction, measurement error and demand can mimic capacity loss.

Can vibration prove bearing failure?

It can support diagnosis with trend and corroborating evidence; high-impact decisions require competent analysis.

What should be measured before removal?

Where safe: flow, pressure, power, temperatures, vibration, oil condition, operating state and package restrictions/settings.

What is checked during overhaul?

Depending on design: bearings, seals, rotors, housing, shafts/gears, fits/clearances and evidence of rubbing, contamination, corrosion or overheating.

Can generic bearing numbers be used?

No. Exact bearings, fits, preload and related data must be verified for the identified airend.

Should rotors always be recoated?

No universal rule applies; rotor/coating condition and approved repair process are design-specific.

Is overhaul always cheaper than replacement?

No. Compare downtime, efficiency, obsolescence, future duty, supportability and package condition.

What if failure repeats after overhaul?

Preserve evidence and investigate root cause before repeating the same rebuild.

How is a rebuilt airend accepted?

Through controlled reinstallation/startup and verification of relevant temperature, vibration, pressure, capacity/power and alarm behaviour.

Can AI decide overhaul?

AI can organise evidence; exact limits, repairability and acceptance require identified equipment data and specialist review.