Frequently asked questions

You need two numbers: air flow (m³/min) and pressure (bar). Pressure is the sum of the hammer's working pressure, hole depth, water in the hole and hose losses. Air flow is the larger of the hammer's rated air consumption and the air needed to clear cuttings, corrected for rock, depth, temperature and altitude. Or use the selection wizard on this site — answer six questions and get recommended models.

No. Pressure has little to do with hammer size. From 3.5" to 14", standard high-pressure hammers run at 1.7–1.8 MPa and ultra-high-pressure hammers at 2.0–2.4 MPa. What changes is air consumption — about 7.5–9 m³/min for 3.5" and 68–80 m³/min for 14". A larger piston already delivers more impact energy at the same pressure; it needs more air to keep its blow rate and clear the hole.

Three things: the hammer's design class (standard 1.7–1.8 MPa, ultra-high 2.0–2.4 MPa), hole depth (deeper holes mean more friction loss and back-pressure), and water — every 10 m of water above the bit adds 0.1 MPa of back-pressure.

Air gets thinner with altitude, so the air actually delivered drops. Published industry data show a loss of roughly 7.5% per 1,000 m above 1,500 m — about 15% at 2,000 m. Size high-altitude projects one step up from the sea-level figure, and choose a turbocharged, high-altitude configuration with enlarged cooling.

Decide by pressure. Up to 13 bar, single-stage is simpler and cheaper to buy. From 20 bar, two-stage is the only option. Between 14 and 19 bar both exist: single-stage costs less up front, two-stage uses less fuel or power at the same pressure — we recommend two-stage for long continuous duty.

It depends on whether there is stable grid power on site. With power, choose electric (DM / LGDY / DMT) — lowest running cost, less noise, longer service intervals. Without power, or if the unit moves often, choose diesel (CM / LGCY). Fixed quarries, urban work and grid-connected mines are typical electric applications.

Models with two sets of figures, such as CM360-31/25-33/18K, have two preset duty points selected with one switch on the controller: 31 m³/min at 25 bar or 33 m³/min at 18 bar. One machine covers both high-pressure and high-flow work, so you don't need to change units when the job changes.

Both share the same engineering standards and quality system. M is the flagship for mining, large projects and continuous heavy duty, with higher-spec power platforms, more cooling margin and more options. LG is the mid-range value series, optimised for purchase cost while keeping reliability — suited to more conventional duty and tighter budgets. Their ranges overlap widely, so choose by budget and how demanding the site is.

The DMT tunnel series: low pressure and high flow (7–8 bar, 36–66 m³/min) with a permanent-magnet variable-speed drive that follows the changing demand of drilling, shotcreting and mucking, plus noise reduction and damp protection for enclosed tunnels.

Take CM430-34/26-36/18K: CM means diesel portable (DM electric, DMT tunnel VSD, LG prefix for the value series); 430 is the power — horsepower for diesel, kW for electric; 34/26 is duty point 1, 34 m³/min at 26 bar; 36/18 is duty point 2; the suffix K means Cummins, X means Xichai and no suffix means Yuchai.

Yes, as a check. Thicker rods leave less annular space, so the same air flow gives a higher up-hole velocity. Aim for about 900–2,100 m/min: below that, cuttings are not cleared, get re-crushed and can jam the string; above it, rods and hole wall wear faster. If the check shows too high a velocity, change the rod size rather than the compressor.

With casing advance the annulus is smaller and the casing has to be driven, so air consumption rises noticeably. Allow 10–15% extra air and one step more pressure. For these jobs we recommend a dedicated calculation by our engineers.

Large holes (over 10") or deep holes (over 200 m) usually need several units in parallel. That involves unit sizing, control strategy and receivers — ask our engineers for a dedicated proposal.

We don't recommend oversizing. A unit far larger than needed runs at low load most of the time, which raises fuel use and wear per cubic metre of air. Add 10–15% margin to the calculated demand and apply the correction factors for altitude and heat.

Yes. Our engineers visit the site and work out air demand, pressure loss, altitude and duty cycle, then tailor connections, duty points and modules — rather than simply picking the nearest standard model.

Day to day the operator uses three buttons: power, start and stop. Warm-up and loading, unloading before stop, pressure control and engine fuelling are all handled by the controller, which prevents shutdowns under pressure and oil carry-over caused by operating errors.

Always unload first and wait until system pressure is below 4 bar. Stopping under pressure is the most common cause of oil at the air filter.

If a phase-sequence alarm appears, switch off and swap any two of the three phases. After electrical repairs, check the rotation of the airend and fan before starting.

In cold weather or with thick oil, jog the compressor with the start button for about 2 seconds, stop it with the emergency stop, wait until the pressure has vented, then start normally. For long-term work in severe cold, choose the pre-heater and cold-start system.

Oil level, fuel (diesel) or phase sequence (electric), air-filter indicator, coolant level, leaks at hoses and fittings, and free ventilation around the unit. After starting, watch discharge temperature and pressure.

Keep the area around the unit well ventilated and stop hot air from recirculating — turn the unit if necessary. Clean the cooler fins more often. In hot regions, choose the enlarged cooling package.

As a rough guide, hourly fuel use is the engine power in kW × 0.16 litres. Actual consumption depends on load, duty, altitude and maintenance — measure on site for an exact figure.

Yes. The machines are designed for long continuous full-load operation, with generous cooling to stay in thermal balance. Filters and oil still have to be changed on schedule and the coolers kept clean.

The high-strength steel chassis, isolation mounts, heavy-duty drawbar and hard-wearing tyres are built for frequent moves on unpaved roads. The LG Series has a parking brake as standard for slopes and uneven ground.

Multi-layer acoustic panels and isolation mounts damp noise from the airend and motor mounts to the canopy lining. The DMT tunnel series and the LG Series have extra acoustic work to help meet limits in plants, towns and tunnels. Ask us for measured sound levels for a specific model.

Use clean diesel to the applicable standard, with a cloud point below the local temperature — otherwise winter starting suffers. Use only the screw-compressor oil grade specified by the manufacturer and do not mix brands or grades. The grade is given in the operation manual.

We advise against it. Different base oils and additive packages can cause carbon, sludge and blocked separator elements when mixed, and may affect warranty claims. Use the specified grade.

By running hours, in three kits: 500 h, 1,500 h and 2,500 h, each with its own parts list. Enter your model in the parts & service lookup to see which parts to change and how many.

Air filters, oil filters, separator elements and compressor oil are consumables, replaced at each service interval; they are normal wear items and not covered by warranty.

The interior follows the service route: oil filter, air filter and separator are within reach of the doors and can be changed without removing other parts. Some models have wide gull-wing side doors. Each unit carries a document box and a tool box.

Our parts are widely interchangeable and reasonably priced. With proper maintenance, the main components typically last more than twice the warranty period.

It depends on dust. In deserts, gravel plains and open-pit mines clean much more often; if discharge temperature rises or a high-temperature alarm appears, check the oil cooler for blockage first.

Drain condensate, fill the fuel tank to prevent rust, and disconnect the battery negative. In cold regions, make sure the coolant protects to the lowest local temperature. Before restarting, check oil level, belt tension and hose seals.

Yes. Too much condensate emulsifies the oil and raises oil consumption. Drain it as the manual specifies — more often in humid climates and with frequent short starts.

When the maintenance indicator says so, not by calendar. In dusty conditions it may be needed earlier. The filter has a main and a safety element; never clean and re-use the safety element.

Yes. For deserts, gravel plains and open-pit mines there is a heavy-duty desert air-filter kit that keeps intake air clean and extends filter life.

Routine filter and oil changes can be done by your own staff — the full procedure is in the documents supplied with the unit. Work on the airend, inlet valve or pressure control should be done by us or an authorised service centre so warranty is not affected.

Air filters, oil filters, separator elements, compressor oil and servo cylinders are consumables and are not covered.

The machine serial number. Our products are continuously improved, so parts can differ between production batches of the same model — the model alone is not enough to identify the right part.

We have a dedicated after-sales department for technical support, and our regional dealers keep service teams and common wear parts in stock to respond locally. Response times are as agreed in the contract and with your local centre.

Besides dealer stock, we keep consumables in stock all year with staff on duty, so parts can be shipped any day.

Leaks are rare in normal use. If one occurs, check hoses, fittings and components and contact your service centre; parts under warranty are handled under the warranty terms.

We export to more than 30 countries and support customers through local dealers plus remote technical support. Find your country on the service network page; if there is no local centre yet, contact our overseas service team directly.

Yes. Our training covers operation, start-up and shut-down, maintenance, the working principles of each system and alarm troubleshooting, on site or remotely, for customers and dealers.

Check in order: is demand higher than the unit's output; are hoses or valves leaking; is the air filter blocked (see the indicator); is the separator element blocked; is the pressure regulator out of adjustment or faulty; is engine speed low (check the fuel filter); is the inlet valve not opening fully (check the control lines). If all are fine, ask a service engineer to check the airend rotors for wear.

Check whether demand exceeds the unit's capacity, whether the air filter is blocked, whether hoses or valves leak, and whether the pressure regulator is out of adjustment or damaged. The regulator is a stock part and can be replaced directly.

Check for low oil in the separator tank, a dirty oil cooler, a loose or damaged fan belt, a failed thermostatic element, blocked oil lines from the thermostatic valve to the airend, a blocked main oil inlet, a blocked oil filter and a blocked scavenge line — and whether hot air is recirculating or the ambient temperature is too high.

Most often because the unit was stopped under pressure without unloading — unload and wait until pressure is below 4 bar before stopping. The next most common cause is a damaged inlet-valve seal, which means replacing the inlet valve.

Check for a blocked scavenge line, leaks in the lubrication system, a damaged separator element, low system pressure (check the minimum-pressure valve and silencer orifice), overfilling and excess condensate.

Check the regulator setting, the blow-down valve, leaks in control lines, a sticking inlet valve, blocked controls, a faulty regulator and the safety valve itself.

Check the pressure regulator (adjust or replace) and the solenoid valve (check wiring or replace).

Check fuel level and fuel system, coolant temperature, level and thermostat, the fan, oil pressure and oil filter, switches and the electrical circuit.

Check for low engine speed, loose pulley or damper bolts, unbalanced pulley, damper or fan, loose or worn mounts, and misfiring or unstable engine speed.

In order: fuel in the tank, blocked fuel lines, the lift pump, a blocked fuel filter and the injection pump.

Low cranking speed (battery, starter and connections), the cold-start aid, fuel quality, a fuel cloud point above ambient temperature, a blocked air filter, air in the fuel system, and injection timing and valve clearance.

Check for too low an idle setting, starting under load (always start unloaded), poor fuel, and air in the fuel system that needs bleeding.

Switch off and swap any two of the three supply phases. Before starting, check the rotation of the airend and fan.

Nine types: phase sequence, voltage out of range, airend overload, airend stall, low water, high discharge temperature, over-pressure, current imbalance and phase loss. The panel shows the fault code; follow the manual supplied with the unit.

Yes. CE compliance documents are available for the models indicated in our brochure — please confirm the model range with our sales team.

Our range is offered with power platforms for several non-road emission and control standards, configured to the destination country's requirements. Tell us the country and the standard when you contact us.

Apply on the Become a Partner page. The process is: registration, qualification review, prospective partner, agreement review and signing, then official partner. Tell us the products you want to represent, your company details and your business background.

Brochures, selection guides and operation & maintenance manuals can be downloaded from the download centre after a short form. Certificates are shown there for reference; for verification or other technical documents, please contact us.

Send us the machine serial number and the parts you need; we identify the exact part numbers, quote and ship. We recommend ordering a set of common wear parts with the machine to avoid downtime.