What size of new borewell compressor do you need?
A new compressor is a ten-year decision, so size it for the work you will actually do across that period, not only the next contract. Begin with three questions: what is the largest hammer you will run, how deep will you drill, and how much water will you meet?
- Hammer air consumption. Take the hammer maker’s chart for each hammer size you plan to use and read consumption at your preferred operating pressure. Consumption climbs steeply with pressure.
- Hole cleaning. Check that flow is enough to clear cuttings at your largest bit and smallest pipe. Drillers commonly aim for roughly 15–25 m/s (about 3,000–5,000 ft/min) of uphole velocity in dry rock.
- Water head. Every 10 metres of water above the hammer adds roughly 1 bar (14.5 psi) of back-pressure. Size pressure for your deepest wet hole, not your average one.
- Site conditions. Summer afternoons above 40 °C and dust from the hole reduce cooling margins. Ask for the machine’s high-ambient rating.
- Future work. Decide whether you need headroom for larger hammers or deeper work. Extra capacity costs fuel and capital, so give it a clear purpose.
Build a pressure budget, not just a cfm figure
A statement such as “buy a 1,000 cfm compressor” is incomplete. The compressor must supply the hammer’s working pressure plus every loss between the discharge valve and the bit: hose and fitting losses, the drill-string and rotation head, the water column above the hammer and any back-pressure from wet, sticky cuttings, with a sensible margin on top. A hammer that works at 20 bar does not mean a 20-bar compressor is enough once the bore is deep and wet.
The same thinking applies to cost. Judge the purchase by cost per metre drilled over its life, which includes fuel, servicing, downtime and resale value, not only the purchase price. A machine that is slightly dearer but drills faster in your formations and holds its pressure in deep water can be the cheaper machine to own.
Our DTH hammer duty comparison tool and DTH hammer air requirement guide walk through the numbers in more detail.
Typical new-machine classes for borewell work
| Class | Flow (cfm) | Pressure | Suits |
|---|---|---|---|
| Medium pressure | 600–900 | 200–250 psig (13.8–17.2 bar) | Agricultural and domestic bores, softer formations, smaller hammers |
| High pressure | 800–1,200 | 250–300 psig (17.2–20.7 bar) | Hard rock, medium to deep bores, larger hammers |
| Deep-hole | 1,000–1,500 | 300–400 psig (20.7–27.6 bar) | Deep wet holes, larger diameters, heavy water inflow |
| Very high pressure | By duty | Up to 35 bar (507.6 psig) | Special deep or high-head drilling |
These are general classes, not a statement of models in stock. Every proposal names the actual model, its rated flow and pressure, and the delivery basis.
Which brands do we supply?
We are an independent multi-brand specialist, not an authorised dealer of any one maker. We have tie-ups with all major and reputed brands. We sell, rent and service machines from ELGi, Atlas Copco, Ingersoll Rand, KAESER, Chicago Pneumatic and other makers. Brand names and trademarks belong to their owners.
Being independent means we can put two or three suitable options in front of you and explain the trade-offs: flow and pressure at your duty, fuel use, engine type, parts availability in your area and service support. You choose the machine; we help you choose well. See compressor brands we support and our multi-brand philosophy.
Engine choices for a new borewell compressor
Nearly all borewell compressors are diesel portables or truck-mounted units, because sites rarely have grid power. The engine is half the machine and often decides running cost.
- Power margin. The engine must hold rated speed at full flow and full pressure in high ambient temperature. A marginal engine is the first thing to suffer on a hot afternoon in a deep hole.
- Fuel consumption. Ask for fuel use at your typical load, not only at full load. Over thousands of hours, fuel is usually the biggest running cost.
- Emissions standard and fuel quality. Newer engines meet stricter emission norms and may be more sensitive to fuel quality and filtration. Check that the engine suits the diesel you will actually buy on remote sites.
- Service network. Engine service and parts must be reachable where you drill, across Telangana, Andhra Pradesh or further afield.
- Engine-driven or separate power. On truck-mounted rigs, some compressors run off the truck engine or a deck engine; on others, the compressor carries its own engine. Each affects weight, fuel and maintenance.
Electric-drive units suit fixed yards and test benches with a reliable supply, but are rarely the first choice for field drilling. See diesel portable compressors for more.
Airend choices: single-stage, two-stage and variable pressure
Most modern borewell compressors use an oil-injected rotary screw airend. The main differences are in staging and pressure control.
| Option | How it works | Why it matters for drilling |
|---|---|---|
| Single-stage screw | One pair of rotors compresses from inlet to final pressure | Simple and robust; common at medium pressures |
| Two-stage screw | Two airends in series share the pressure ratio | Better efficiency and lower temperatures at high pressures |
| Variable pressure / flow | Operator selects pressure; flow adjusts within the engine’s power | One machine can run high flow at lower pressure or high pressure at lower flow |
| Booster with primary compressor | A booster raises the pressure of a primary machine’s air | Reaches very high pressures for deep holes |
Pressure costs power. As a rule, each extra bar of discharge pressure takes about 7% more power at the same flow, so buying more pressure than you need costs fuel every hour. Read more on variable pressure portable compressors.
Features worth checking before you sign
- Safety shutdowns for high discharge temperature, low engine oil pressure and high coolant temperature, plus a correctly rated safety valve.
- Cooling package sized for high ambient temperature, with cores that are easy to reach and clean of drilling dust.
- Heavy-duty air filtration suited to dusty sites, with a restriction indicator.
- Service access: filters, oil drains and separator reachable without dismantling the canopy.
- Fuel tank size for a full shift or more, and good fuel filtration with a water separator.
- Controls and gauges that a site operator can read and understand.
- Chassis, axle and towing arrangement suited to rough approach roads, or skid mounting for truck rigs.
Comparing offers fairly
Two machines with the same headline flow can be very different purchases. Put each offer on one sheet and compare:
- rated flow at your working pressure, under stated reference conditions;
- engine make, rated power and fuel use at typical load;
- what is included: hoses, lubricator, tool kit, documents, delivery, commissioning and operator familiarisation;
- the manufacturer’s written warranty terms and who handles claims;
- parts availability and the route for service in your area.
Warranty terms come from the manufacturer and are stated in writing in each proposal. Finance, trade-in or buyback are not assumed; ask if you need them.
Service backing after you buy
A new compressor that cannot be serviced near your work becomes an expensive problem. We support what we sell with servicing, breakdown repair, overhaul and spares. Parts are identified from the machine’s make, model, serial number and nameplate, and fit is confirmed before quoting. If you run several units, we can plan maintenance across the fleet; see borewell compressor service and repairs and compressor AMC.
If your demand is uncertain or seasonal, compare borewell compressor hire before buying. If budget is the main constraint, a used or reconditioned compressor may be worth a look.
How Reddy Compressors helps
For borewell rig owners we supply all types, all brands and all models of borewell compressors: new sales, used and refurbished machines, rentals, service and spare parts.
Since 2002 we have sold, rented and serviced compressed-air equipment for industry and drilling. As an independent multi-brand specialist we help you size the machine against your hammer and depth, shortlist suitable models from several makers, and compare offers on one sheet. We then deliver, commission and support the machine with our team of more than 20 service engineers and technicians.
Our service teams cover all of Telangana and Andhra Pradesh, and we supply new compressors and spares across India. For long-term projects we can supply a brand-new compressor directly to site. Our office is at Srinilayam, 12-13-200, First Floor, Street No. 1, Tarnaka, Secunderabad 500017. Call +91 99590 60718 or +91 92468 88812, WhatsApp +91 99590 60718, or email reddycompressors@gmail.com.
What to send us
- Rig make and model, hammer sizes and bit diameters you plan to use.
- Typical and maximum drilling depth, water-strike depth and formation.
- Expected running hours per year and regions you work in.
- Any preferred brand, engine or mounting (trailer, skid or truck).
- Delivery location and preferred timing.
Frequently asked questions
Which compressor is best for borewell drilling?
There is no single best compressor. The right one matches your largest hammer’s air consumption at your working pressure, clears cuttings from your largest hole and has enough pressure for your deepest wet bore. Most borewell work needs 600 to 1,500 cfm at 200 to 400 psig. We compare models from several makers against your duty.
What pressure compressor do I need for a 1,000 ft borewell?
It depends mainly on how much water stands above the hammer. Roughly every 10 metres of water adds about 1 bar of back-pressure, on top of the hammer’s working pressure. A deep wet bore of around 300 metres often needs 300 to 350 psig or a high-pressure unit up to 35 bar. Send us water-strike depth and hammer details to confirm.
Should I choose a single-stage or two-stage borewell compressor?
Single-stage screw compressors are simple and common at medium pressures. Two-stage machines share compression between two airends, which runs cooler and more efficiently at high pressures. If most of your work is deep and above about 250 psig, a two-stage or variable-pressure machine is worth comparing. Fuel use at your typical load should decide it.
Are you an authorised dealer for borewell compressor brands?
No. Reddy Compressors is an independent multi-brand specialist. We sell, rent and service ELGi, Atlas Copco, Ingersoll Rand, KAESER, Chicago Pneumatic and other makes, but we are not an authorised dealer of any of them. This lets us compare several makers against your duty and recommend the one that suits your work.
What warranty comes with a new borewell compressor?
The warranty on a new machine comes from its manufacturer and varies by make and model. We state the applicable terms in writing in each proposal, including what is covered and how claims are handled. We do not quote a general warranty period on this page because it depends on the specific machine you choose.
Should I buy or hire a borewell compressor?
Buy if you have steady drilling work across most of the year and can maintain the machine. Hire if your work is seasonal, a single contract or uncertain, or if you want to try a size before buying. Our rental versus ownership calculator compares the two using your own running hours and costs.
Related pages
Calculators and worked examples
These tools give indicative figures for screening, comparison and for preparing an enquiry. They run in your browser and send nothing. No prices or tariffs are assumed: enter your own to see costs. Efficiencies and other figures shown are example values: replace them with your own. Results are not a performance guarantee or a design certificate; final selection is confirmed by a service engineer against the machine data sheet and the site.
DTH hammer duty against two compressors
Check whether each of two compressors can supply a DTH hammer’s documented air consumption at the pressure the hammer needs, after hose, string and water-column losses, and with what margin.
The worked example below shows the method with fixed numbers. Turn on JavaScript to change the inputs.
Worked example
Inputs
- Hammer working pressure at the hammer (bar g): 21
- Hammer air consumption at that pressure (cfm): 950
- Pressure loss from compressor to hammer (bar): 1
- Water column above the hammer to be lifted (m): 0
- Compressor A: maximum working pressure (bar g): 17
- Compressor A: data-sheet flow at the required pressure (cfm): 1150
- Compressor B: maximum working pressure (bar g): 24
- Compressor B: data-sheet flow at the required pressure (cfm): 1000
- Site derating of delivered flow: heat, altitude, condition (%): 0
Result
- Hammer working pressure: 21 bar g = 305 psig
- Water column allowance: 0 bar
- Required compressor discharge pressure: 22 bar g = 319 psig
- Hammer consumption: 950 cfm = 26.9 m³/min
- Compressor A: Fails: cannot reach 22 bar g (maximum 17 bar g); its flow does not count
- Compressor B: flow available at 22 bar g: 1,000 cfm = 28.3 m³/min
- Compressor B: margin: +5.3 % (covers the duty)
- Result: Only compressor B covers the duty
Method. Required discharge pressure = hammer working pressure + pressure loss from compressor to hammer (hose, swivel, drill string, check valves) + water column to be lifted (0.0981 bar per metre of water). A compressor whose maximum working pressure is below the required pressure fails, whatever its flow. Available flow = data-sheet flow at the required pressure × (1 − site derating). Margin (%) = (available flow − hammer consumption) ÷ hammer consumption × 100. Use the same flow basis (FAD or scfm) for hammer and compressor. 1 bar = 14.504 psi; 1 m³/min = 35.31 cfm. Hole cleaning (annular velocity) is a separate check.
What to take from it. Compare flows at the same pressure. More cfm at a lower pressure does not run a hammer that needs higher pressure.
Technical content reviewed by D. Srinivas Reddy, Managing Partner and service engineer, Reddy Compressors. Last updated 17 October 2026. How our engineering content is reviewed.
Annular area and return velocity
In drilling, the air must lift the cuttings up the annulus. Check the return velocity from the hole and rod size.
The worked example below shows the method with fixed numbers. Turn on JavaScript to change the inputs.
Worked example
Inputs
- Hole diameter (mm): 115
- Rod outside diameter (mm): 89
- Free air supplied (m³/min): 12
- Bottom-hole back pressure (bar g): 1
- Target return velocity (m/s): 15
Result
- Annular area: 41.7 cm²
- Return velocity: 24.16 m/s = 4,757 ft/min
- Free air needed for the target velocity: 7.45 m³/min = 263 cfm at 15 m/s
- Assessment: Within the commonly quoted range
Method. Annular area = π/4 × (D_hole² − D_rod²). Actual flow at the back pressure = free air × (P_atm / (P_back + P_atm)). Velocity = actual flow ÷ area. A return velocity often quoted for efficient cuttings lift is around 15–25 m/s; confirm for your material.
What to take from it. Low return velocity leaves cuttings in the hole; very high velocity wears the rods and hammer. Both are warnings, not verdicts.