The district from a compressed-air point of view
Prakasam divides into three compressed-air countries. The granite belt around Chimakurthy, Ballikurava, Martur, Podili and Kanigiri is high-pressure, high-flow, dusty, hot work: hundreds of quarries, each with portable diesel compressors on the bench, and the cutting and polishing yards along the Ongole road that run electric screw compressors with dryers. The coast from Chirala through Ongole to Kandukur is aquaculture, tobacco processing, dairy, rice and the port-linked trade, which need clean, dry, often food-grade air in a humid, salty climate. The interior around Markapur, Giddalur and the Nallamala edge is slate and limestone quarrying, cement-linked work and borewell drilling in hard rock. Ongole town itself has workshops, hospitals, colleges, construction and the district’s trading economy.
| Area | Approximate road distance from Tarnaka | Typical route | What we are usually asked for there |
|---|---|---|---|
| Chimakurthy, Ballikurava and Martur | 320–340 km | Via Nalgonda, Miryalaguda and Vinukonda, or via Guntur | Quarry drilling compressors, wire-saw air, cutting and polishing yards, drilling contractors |
| Ongole town | 340–370 km | Via Chimakurthy or via NH 16 | Cutting yards, workshops, hospitals, construction, aquaculture processors |
| Podili and Kanigiri | 300–330 km | Via Miryalaguda and Vinukonda | Granite quarries, borewell rigs, agro-processing |
| Markapur and Giddalur | 290–330 km | Via Nalgonda and Markapur road | Slate and limestone quarries, cement-linked contractors, drilling |
| Chirala, Vetapalem and Kandukur | 350–400 km | Via Guntur or NH 16 | Aquaculture, tobacco, rice, handloom units, coastal sites |
Black granite: The hardest stone and the hardest duty
Chimakurthy’s stone is dense and hard, and the quarrying method has moved from blasting towards drilling, wire sawing and controlled splitting to protect the block, which means more compressed air per cubic metre of stone than almost any other quarrying in the two states.
| Operation | Equipment on air | Pressure and flow | What decides the compressor |
|---|---|---|---|
| Primary bench drilling and line drilling | DTH hammers on crawler or wagon drills, 3–4.5 inch holes, deep vertical and horizontal lines | 17–25 bar g at 15–30 m³/min | Pressure at the hammer after hose and heat losses, flow for several drills from one machine, fuel consumption over long shifts |
| Secondary drilling and splitting | Jackhammers, plug-and-feather drilling, pneumatic splitters and wedges | 7–8 bar g at 5–15 m³/min | A separate lower-pressure machine rather than a high-pressure machine throttled down |
| Diamond wire sawing | Flushing and cooling air where water is short, pneumatic tensioning, blow-down | 7–8 bar g, intermittent | Receiver sizing for intermittent draw, dry air for pneumatic controls |
| Block handling and loading | Pneumatic tools, tyre bays for loaders and trucks, cleaning | 7–8 bar g, intermittent, large receivers | A receiver sized for inflating loader tyres |
| Cutting and polishing yards | Gang-saw and multi-wire blow-down, polishing-line cylinders, resin and epoxy lines, edge tools | 6–8 bar g at 3–15 m³/min electric screw | Dry, clean air for resin and polishing, protected intake against stone dust and slurry mist |
Four lessons from the Chimakurthy belt are worth stating plainly, because each one costs quarries money every season. First, a portable diesel compressor rated at 25 bar g and 25 m³/min delivers less of both on a 44 °C bench in May, and a machine chosen with no margin runs flat out, overheats and wears out early; we size with a summer derating margin and compare makes on heat rating and specific fuel consumption. Second, one high-pressure machine feeding several drills through long hoses loses pressure in the hoses before it reaches the hammers; hose diameter, length and the number of drills decide the pressure at the hammer, and the DTH drilling guide sets out the arithmetic. Third, a high-pressure machine throttled down to run jackhammers and splitters all day burns fuel for nothing; a 7 bar machine for the secondary work pays for itself in diesel. Fourth, black-granite dust is fine and abrasive, and intake filters, radiators and oil coolers are cleaned on an inspection calendar, not the manual’s. We service quarry compressors of every make, supply the spares they consume, and supply new and inspected used quarry compressors with test sheets.
Cutting and polishing yards along the Ongole road
The yards that saw, polish and pack the stone for export run on electric screw compressors, and their problems are cleanliness and reliability rather than pressure. Stone dust and slurry mist are drawn into compressor rooms placed inside the shed; resin and epoxy lines fail when the air is wet or oily; polishing-line cylinders wear when the air carries dust; and a yard with a container to load cannot stop for a compressor fault. The answers are a compressor room outside the shed with a clean-side intake and heavier filtration, a refrigerated dryer sized for a 45 °C inlet with the coastal humidity allowed for, a coalescing filter pair before the resin line, electronic drains, a receiver sized for the blow-down peaks, and a maintenance contract with a standby arrangement. The receiver sizing page and the refrigerated dryer notes give the figures.
Aquaculture, tobacco, dairy and the coast
The Prakasam coast is aquaculture country, with hatcheries, feed mills and processing plants around Ongole, Chirala and Kandukur that need food-grade air in a wet, salty environment, and the question of blower against compressor for aeration duties; the notes on the Nellore page apply directly. Tobacco grading and processing uses air for conditioning and packing in a humid shed; dairy plants need food-grade air for filling and packing; rice mills need stable, dry, clean sorter air. Coastal sites are specified for salt: coated coolers, sealed cabinets, coated receivers, dryers sized for the humidity and electronic drains, as set out on the Visakhapatnam page. The food-grade air page explains the air-quality classes.
Markapur slate, limestone and the interior bores
Markapur’s slate and limestone quarries drill and split stone at 7 to 25 bar g in dust and heat, and the cement-linked contractors of the belt need portable air for maintenance, blasting and construction. The interior around Giddalur, Kanigiri and Podili is drilled for borewells in hard rock, often deep, with the pressure-margin, water-column and booster questions of the rest of the Deccan; the DTH drilling guide and the booster-assisted drilling page set out the method.
Key facts for a Prakasam site
- Distance: about 330 km from Tarnaka to Chimakurthy by the Nalgonda–Miryalaguda–Vinukonda road and about 370 km to Ongole; a rental delivery is a long day each way; service visits are planned trips, often grouped with Nalgonda and Guntur work.
- Climate: hot; May highs around 42 °C inland and humid on the coast, with the north-east monsoon heavier than in the north and a cyclone season from October to December.
- Atmosphere: black-granite dust at quarries and yards, slate dust at Markapur, salt and humidity on the coast, red-soil dust at rig sites.
- Fuel: diesel is the largest running cost of a quarry compressor by far; the own-or-hire calculator shows how it dominates.
- What we do here: sales of new machines through our supply tie-ups, inspected used and refurbished machines from our Secunderabad yard, rental from our own fleet by the month, service and repair of all makes, maintenance contracts, airend, engine and booster overhauls in Secunderabad, spares, dryers and filters.
Sales: New, used and refurbished
A quarry buying a 25 or 30 m³/min, 25 bar g drilling compressor is making a decision that fuel and heat will dominate for ten years; we size for the drills and hammers that will actually run from it, the hose lengths and the bench, with a summer margin, and we compare makes on heat rating, specific fuel consumption and how the machine is built for dust. We have supply tie-ups with all major makes, we are not the authorised dealer of any, and we recommend from the job; the selection guide explains the method. For a yard, an inspected used or refurbished electric screw compressor from our yard, load-tested with a six-month warranty and its test sheet, with a new dryer, is often the right value; inspected used quarry compressors come with their test sheets and a plain statement of the pressure and flow they deliver. The used compressors page sets out what is inspected.
Rental in the granite belt
Rental here is by the month, because the delivery is a long day each way. Our fleet supplies portable diesel compressors for bench drilling, line drilling, splitting and construction, delivered with hoses and a commissioning check by a service engineer, and skid-mounted electric screw compressors with dryers to keep a cutting yard running through a season or an overhaul. Fuel for a diesel machine is the hirer’s. A quarry opening a new bench, or a yard with an export order it cannot miss, usually hires for the season and buys once the duty is known.
Service, repair and maintenance contracts
| Situation | What we need first | What then happens |
|---|---|---|
| Quarry compressor losing pressure or overheating | Nameplate, hours, gauge readings under load, number of drills and hose lengths, photographs of the cooler and filters | A service engineer with filters, cooler-cleaning equipment, the likely valve or sensor and instruments to test under load on the bench; often a hose or sizing answer as much as a repair |
| Yard compressor fault, wet or oily air at the resin line | Compressor and dryer nameplates, controller display, drain condition, room location | Telephone diagnosis, then a visit with the parts the symptom points to; the fix is often in the dryer, drains or intake |
| Rig compressor stalling at depth | Nameplate, hours, hammer, hole depth and water level | A sizing check and a visit with filters and valves; a booster where the water column takes the pressure |
| Overhaul, airend, engine or booster rebuild | Hours, noise and vibration history, oil analysis if available | The unit goes to our Secunderabad workshop; a rental machine covers the quarry or yard |
| Maintenance contract | Machine list with nameplates, hours, criticality, season dates | A visit calendar from hours and seasons, consumables carried, dryers and drains included, visits grouped with other Prakasam work |
At this distance a maintenance contract, with filters and a thermostatic element held on site, is what turns unplanned trips into planned ones; the AMC page explains the structure.
Spare parts to Chimakurthy and Ongole
Intake filters, separator elements, oil, belts, inlet and minimum-pressure valves, thermostatic elements, hammer and hose fittings, booster valves and seals, dryer filters, drain valves and controller sensors are what the belt consumes, and black-granite dust consumes intake filters faster than almost any other quarrying we serve. Parts travel with the service engineer for planned work or by road and courier for a quarry’s own fitter. We identify a part from the nameplate and a photograph of the component, not from the canopy name; the spare parts page explains what to photograph. A quarry should hold a season of intake filters, belts, a thermostatic element and hose fittings on site.
A worked example: One compressor feeding three drills at Chimakurthy
A quarry runs three crawler drills with 4 inch DTH hammers from one 25 bar g, 30 m³/min portable compressor through 60 to 90 metres of hose, and finds the farthest drill slow and the compressor running flat out all afternoon. Each hammer wants about 8 m³/min at 17 to 20 bar g; three together want about 24 m³/min at the hammers, which the compressor can supply at the reference condition but not on a 44 °C bench once engine and airend derate. Worse, the long, undersized hoses drop several bar before the farthest hammer, so it works at 15 bar g while the nearest works at 19. The answer is in three parts: larger-bore hose to the far drills and a manifold near the bench so that each drill has a short run; a second compressor so that the three drills are fed by two machines with a summer margin rather than one at its limit; and a separate 7 bar machine for the splitters and jackhammers that were also being run from the high-pressure supply. Fuel per cubic metre of stone falls because neither high-pressure machine is working flat out, the far drill speeds up because it sees the pressure the hammer was designed for, and the cooler-clean and filter intervals are set at the first service from what the filters look like.
Common mistakes at Prakasam sites
- Feeding several drills through long, undersized hoses and blaming the compressor for the far drill’s slowness.
- Choosing a quarry compressor by nameplate flow with no margin for a 44 °C bench.
- Running a high-pressure machine throttled down for splitters and jackhammers all day.
- Putting a yard compressor inside the shed where stone dust and slurry mist are thickest.
- Installing an inland-specification compressor at a coastal aquaculture plant.
- Ordering a part by the canopy name rather than the number on the component.
How Reddy Compressors helps
Chimakurthy’s quarries are among the most demanding compressed-air users anywhere in the two states, and the belt is where much of what we know about multi-drill high-pressure supply was learned. We are an independent, multi-brand business with supply tie-ups across all major makes, our own rental fleet, our own yard of inspected used machines, a workshop for airend, engine and booster work, and more than 20 service engineers and technicians, all working from Tarnaka in Secunderabad.
What to send us
- A photograph of the compressor nameplate and, for a fault, the gauges or controller under load.
- Where the site is: the quarry, yard, processing plant or village and the nearest landmark.
- For a quarry: the drill and hammer models, hole sizes, the number of drills on one compressor and the hose lengths.
- For a yard or plant: the list of air users, the pressure, the air-quality requirement and the hours.
- For rental: the duty, pressure, flow, period, and whether the site has three-phase power.
Frequently asked questions
Do you have a branch in Ongole or Chimakurthy?
No. Our only office and yard is at Tarnaka, Secunderabad, about 330 km from Chimakurthy. We work in the district as projects and contracts: rental by the month, maintenance contracts with a calendar, and service visits grouped with other Prakasam, Nalgonda and Guntur customers.
Watch
Short explainers on this topic
Slide-by-slide engineering explainers from Reddy Compressors. More in the video library.
Can one compressor run three drills at Chimakurthy?
Only if its flow, after summer derating, covers all three hammers with margin and the hoses are short and large enough to deliver the pressure to the farthest drill. Send the drill and hammer models and the hose lengths and we will check it.
What pressure does black-granite line drilling need?
DTH hammers for 3 to 4.5 inch holes want 17 to 20 bar g at the hammer, which means more at the compressor once hose and heat losses are counted. Splitters and jackhammers want 7 to 8 bar g and are best run from a separate machine.
Do you rent quarry compressors for a season?
Yes, from our own fleet, delivered by road, commissioned on site and hired by the month. Fuel is the hirer’s.
Can you supply dry, clean air for resin and polishing lines at a yard?
Yes. A compressor room outside the shed, a dryer sized for the humidity, coalescing filtration before the resin line and electronic drains, designed as part of the supply.
Can you service a compressor of a make you did not supply?
Yes. We service and repair every major make of compressor, booster and dryer and supply parts for them. Send the nameplates.
Do you cover the aquaculture plants on the Prakasam coast?
Yes. Food-grade lubricated or oil-free compressors with the filtration and drying for a wet, salty environment, and an honest answer on blower against compressor for aeration.
Is a used quarry compressor sensible?
For a known duty, yes, provided its pressure and flow are stated honestly. Inspected used quarry compressors from our yard come load-tested with a test sheet and a plain statement of what they deliver.
Related pages
Technical content reviewed by D. Srinivas Reddy, Managing Partner and service engineer, Reddy Compressors. Last updated 4 November 2026. How our engineering content is reviewed.