Product
Ingersoll Rand 99273906 Air Filter Element | M37 Compressor OEM Part
Ingersoll Rand 99273906 air filter element for M37 rotary screw compressors rated 6 m³/min at 0.7 MPa. 270 mm OD × 120 mm H, 2–10 μm filtration, ≥98% efficiency at ≥5 μm, 380 g dust-holding capacity. Export-ready OEM/ODM supply with part-number verification and bulk packing.
- Export packaging & documentation support
- OEM / ODM customization available
- Sample and bulk order workflow
Product Overview
99273906 is the intake air filter element for the Ingersoll Rand M37 rotary screw air compressor. It is mounted inside the air filter housing at the intake, upstream of the inlet valve. As the compressor draws in ambient air, dust, sand, fibres, water mist and oil mist are captured by the filter media before reaching the airend — surface filtration blocks coarse particles while depth filtration holds fine ones. Only clean air is allowed into the rotor meshing zone.
The condition of this element directly affects airend service life. Unfiltered air accelerates wear on rotors and bearings and contaminates the downstream oil separator element, oil filter and lubricant, shortening all three at once. A heavily clogged element also restricts intake volume, reducing discharge capacity and raising energy consumption; in extreme cases oil carry-over can cause airend seizure. Replacing the air filter on schedule is the lowest-cost protection available for the airend.
Core Specifications
| Item | Value |
|---|---|
| Part number | 99273906 |
| Product name | Air Filter Element |
| Application | Ingersoll Rand M37 rotary screw compressor |
| Unit discharge | 6 m³/min @ 0.7 MPa |
| Outer diameter | 270 mm |
| Height | 120 mm |
| Effective filtration area | Approx. 1.3 m² |
| Filtration rating | 2–10 μm |
| Filtration efficiency | ≥98% for particles ≥5 μm |
| Initial pressure drop | Approx. 0.5–1.0 kPa |
| Alarm resistance | 6.0–6.5 kPa |
| Recommended service interval | Approx. 2,000 hours or 3 months, adjusted to operating conditions |
Technical Parameters
Filtration Performance
| Parameter | Value / Notes |
|---|---|
| Filtration rating | 2–10 μm |
| Filtration efficiency | ≥98% for particles ≥5 μm |
| Filter class | Not classified under the EN 779 G/M/F ventilation filter system; air filter elements are characterised per ISO 5011 by efficiency, intake resistance and dust-holding capacity |
| Dust-holding capacity | Approx. 380 g |
Flow and Resistance
| Parameter | Value / Notes |
|---|---|
| Rated air flow | Matched to M37 unit discharge of 6 m³/min @ 0.7 MPa |
| Face velocity | Approx. 0.077 m/s |
| Initial pressure drop | Approx. 0.5–1.0 kPa |
| Operating differential range | Approx. 1.0–6.0 kPa |
| Alarm / final resistance | 6.0–6.5 kPa |
| Pressure drop vs. energy | Each 1 kPa rise in intake resistance increases unit energy consumption by approx. 1% |
Pressure Drop and Energy Consumption
Based on an M37 discharge pressure of 0.7 MPa (gauge) and atmospheric pressure of 101.3 kPa, intake resistance raises the compression ratio:
| Intake resistance | Compression ratio | Relative energy increase |
|---|---|---|
| 0 kPa (new element) | 7.91 | Baseline |
| 2 kPa | 8.07 | +2.0% |
| 4 kPa | 8.24 | +4.1% |
| 6 kPa (near alarm) | 8.41 | +6.3% |
From new to alarm condition (0 → 6 kPa), unit energy consumption rises by roughly 6% over the element's life. On a 37 kW unit running 6,000 hours per year, this represents continuous excess power draw during the later part of the service interval. The saving from running a clogged element is far smaller than the additional electricity cost.
Dimensions and Installation
| Parameter | Value / Notes |
|---|---|
| Dimensions | 270 mm OD × 120 mm H |
| Construction | Pleated (wound pleated filter paper) |
| Effective filtration area | Approx. 1.3 m² |
| Pleat count | Approx. 150 pleats |
| Pleat spacing | Approx. 4.8 mm |
| Mounting interface | End-cap located, matched to the M37 air filter assembly |
| Sealing | Face seal (axial compression) |
Procurement note: when cross-checking replacements, 270 mm OD and 120 mm height are the two most direct comparison dimensions. The ML37 / MU37 models in the same series use 39588777 (130 mm OD × 250 mm H) — the size difference is substantial and the two are not interchangeable.
Materials
| Parameter | Value / Notes |
|---|---|
| Media | Imported wood-pulp filter paper (industry-common US HV or Korean Ahlstrom media) |
| Media weight | Approx. 130 g/m² |
| Inner / outer support | Galvanised steel perforated cage, approx. 0.6 mm thickness, open area ≥45% |
| End caps | Metal end caps (galvanised steel) with polyurethane bonding |
| Seal | Nitrile rubber (NBR) gasket |
| Bonding | Polyurethane (PU) hot-melt adhesive |
Operating Tolerance
| Parameter | Value / Notes |
|---|---|
| Operating temperature | −10 to +100 °C |
| Relative humidity | ≤80% RH, no condensation |
| Burst strength | Filter paper approx. 200–400 kPa (per ISO 2758 paper burst strength) |
| Collapse pressure | Element designed for differential pressure ≥10 kPa |
| Special features | No flame-retardant, anti-static or moisture-resistant specification listed for this part number |
Service Life and Maintenance
| Parameter | Value / Notes |
|---|---|
| Service life | Approx. 2,000 hours or 3 months |
| Actual replacement interval | Reduce to under 1,000 hours in dusty, sandy or humid environments; follow the differential pressure alarm |
| Storage shelf life | Approx. 2–3 years (unopened, dry and ventilated conditions) |
Applicable Standards
| Item | Details |
|---|---|
| Product standard | ISO 5011 (inlet air cleaning equipment for internal combustion engines and compressors — performance testing), evaluated on efficiency, intake resistance and dust-holding capacity |
| Commonly cited test standards | ISO 2941 / 2942 / 2943 / 3723 / 3724 / 3968 |
| Standard applicability note | The ISO 29xx / 37xx series are general test methods for hydraulic fluid power filter elements (burst pressure, structural integrity, material compatibility, axial load, flow fatigue, pressure drop vs. flow). If a supplier can only provide hydraulic filter standards, request ISO 5011 data or the OEM specification sheet. |
Installation and Maintenance Procedure
Single-person task, approximately 20–30 minutes.
- Shut down, isolate and depressurise. Press the emergency stop or shutdown button, disconnect the main power and apply lockout/tagout. Open the receiver tank drain valve to release system pressure and wait until the separator tank gauge reads zero. Criterion: gauge at 0 and no residual air flow noise.
- Locate and open the air filter housing. On the M37 the filter assembly is at the intake end of the unit. Release the housing clamp or end-cover bolts and remove the cover. Criterion: cover undistorted, clamp not seized; free a seized clamp before proceeding.
- Remove the old element and inspect it. Pull the element straight out and examine dust distribution and media condition. Criterion: replace immediately if the media is torn, perforated, the end cap is debonded or the sealing face is flattened — even before the interval is due. Black oily sludge on the outer surface indicates abnormal oil mist in the intake; check the upstream environment.
- Clean the housing interior thoroughly. Wipe the inner walls and base with a lint-free cloth. Do not blow compressed air hard into the housing — this drives dust into the intake passage. Criterion: no loose dust on inner walls, sealing face flat and free of debris.
- Verify the new element. Compare old and new: 270 mm OD, 120 mm height, face seal intact with no gaps, media undamaged. Criterion: all three dimensions and the visual check pass; if any item fails, do not install — re-verify the part number.
- Fit the new element and refit the cover. Place the element vertically into the housing, confirm it is fully seated at the base and the sealing face is in contact with no trapped material. Refit the cover and tighten the clamp or bolts evenly in a diagonal sequence. Criterion: even gap between cover and housing, no visible skew.
- Start-up check. Restore power and run the unit for 5–10 minutes. Criterion: no abnormal whistling or intake noise at the intake (unusual noise usually means the seal is not compressed or the element is not seated); the air filter differential pressure indicator should read in the green zone.
The one hard rule: never start the unit before the element is seated. Running without an element or with an uncompressed seal sends unfiltered air straight into the airend and can cause irreversible wear in a short time.
Frequently Asked Questions
Are 99273906 and 39588777 interchangeable?
No. 39588777 is for the ML37 / MU37 models with a 130 mm OD × 250 mm H element; 99273906 is for the M37 with a 270 mm OD × 120 mm H element. The size difference is more than double and they will not physically fit the same housing. Always cross-check by model plus part number.
How often should it be replaced?
Under standard conditions, approximately 2,000 hours or 3 months, whichever comes first. This is not a fixed deadline: in high-dust locations (cement, foundry, woodworking, mining) reduce to under 1,000 hours; in clean environments with low running hours it may be extended. The most reliable method is to follow the air filter differential pressure indicator and replace at the alarm point.
What happens if it is not replaced?
Failure cascades, and the economics are clear. As dust accumulates, intake resistance rises; on compression ratio theory, resistance from 0 to 6 kPa increases unit energy consumption by about 6.3%. If the media tears or the seal fails, unfiltered air reaches the airend and dust contaminates the screw rotors, bearings, oil separator element, oil filter and lubricant — repair cost escalates from the price of one element to the level of an airend overhaul.
How do I know it needs replacing?
Three signals: the differential pressure indicator enters the alarm zone (approx. 6.0–6.5 kPa); visual inspection after shutdown shows the media fully covered in dust with no visible pleats; discharge capacity drops while current/energy consumption rises. Any one signal means replace.
Can the element be cleaned and reused?
Not recommended. This is a pleated paper element designed as a single-use part. Blowing compressed air from inside out only removes surface dust; fine particles trapped in the depth of the media cannot be cleared, and the air pressure can easily fracture fibres or distort pleat spacing, creating invisible channels that let unfiltered air pass. Reusing a cleaned element means it looks clean but has actually failed — the risk outweighs any benefit.
What else should be checked when replacing the air filter?
Also check: whether the differential pressure indicator is still responsive (it should return normally after reset), the intake hose for cracks or looseness, the housing seal for ageing, and the inlet valve for correct operation. These parts work together with the air filter; replacing only the element without checking the surrounding components often leads to intake problems recurring shortly after.
Is this a genuine OEM part?
The 99273906 described on this page is an Ingersoll Rand OEM part number. When ordering, verify against the part number itself — it is the only unambiguous identifier. Do not order based solely on "fits M37" or visual similarity.
Do other M-series models use the same air filter?
No. Ingersoll Rand M-series air filter specifications differ by model: M22 uses 39588470 (130 mm OD), M37 uses 99273906 (270 mm OD), M55 uses 39708466 (278 mm OD), and ML37 uses 39588777. Being in the same series does not mean the same element — verify model by model.
What is the most common installation error?
Two: trapping material on the sealing face or compressing the cover before the element is fully seated, causing a leak; and tightening cover bolts in a single-side sequence, which skews the cover and distributes load unevenly. The correct method is to confirm seating, then tighten evenly in a diagonal cross pattern in stages.
Are there storage requirements for new elements?
Yes. Moisture causes the filter paper to swell and deform, reducing efficiency, and corrodes the metal cage. Store on indoor shelving in a dry, ventilated area, off the floor and away from walls, water and oil. Use within 2–3 years while unopened. Follow first-in-first-out and avoid long-term stockpiling.
Compatible Machine Models
| No. | Model | Unit discharge | Element OD × H |
|---|---|---|---|
| 1 | M37 | 6 m³/min @ 0.7 MPa | 270 mm × 120 mm |
| 2 | M22 | 3 m³/min @ 0.7 MPa | 130 mm × 151 mm |
| 3 | M55 | 10 m³/min @ 0.7 MPa | 278 mm × 125 mm |
| 4 | ML37 / MU37 | 6 m³/min @ 0.7 MPa | 130 mm × 250 mm |
| 5 | 30S | 3 m³/min @ 0.7 MPa | 130 mm × 123 mm |
| 6 | 50S | 6 m³/min @ 0.7 MPa | 216 mm × 318 mm |
| 7 | 75S | 10 m³/min @ 0.7 MPa | 278 mm × 251 mm |
How to Read the Table
- This page covers row 1, the M37. The other rows are listed only for series comparison, to help you avoid a mis-purchase.
- Row 4 (ML37 / MU37) and row 1 (M37) share the same unit discharge, but the air filter dimensions are completely different. Equal discharge does not mean a common element — this is the most commonly confused point in the series.
- If your unit nameplate model is not listed, send a photo of the nameplate and the full model number; we will cross-check by part number before you order.
Model Generation Note
The Ingersoll Rand M37 exists in different production generations. The product described here is the intake filter for earlier M37 models. Newer M37-75 series units (covered by the SL/SM37-75KW operation parts manual) use a different part number system in their parts manuals. If your unit is a recent build, verify against the parts manual supplied with the machine, or contact us to confirm by unit serial number. In practice the most reliable confirmation is still to read the part number from the old element itself.
Related Components
The M37 intake and lubrication system has seven components maintained on the same cycle as the air filter. They are listed below by location, function and inspection point. For specific part numbers, refer to the unit's parts manual.
| Component | Location | Function | Inspection point |
|---|---|---|---|
| Oil filter element | Main oil circuit, between cooler and airend | Removes wear debris and sludge from lubricant, protecting bearings and rotors | Replace together with the air filter; after replacement check the housing seal for oil seepage |
| Oil separator element | Inside the separator tank | Separates oil mist from compressed air and returns it, controlling oil carry-over | When replacing, also check the return line for blockage (poor return directly causes high oil carry-over) |
| Air filter differential pressure indicator | On the air filter assembly | Indicates element clogging and signals replacement timing | Should return normally after reset; a reading that never moves means it has failed and should be replaced |
| Coolant filter element | Coolant circuit, between cooler and filter | Keeps coolant clean, preventing scale and debris deposits | Replace together with the oil filter element |
| Thermostatic control valve element | Between cooler and filter | Controls whether coolant passes through the cooler, maintaining airend operating temperature | If the unit runs cold long-term or gives high-temperature alarms, check the thermostatic valve first |
| Breather filter | On the separator tank | Balances tank pressure and prevents external dust entering the oil circuit | Check on the same cycle as the air filter; shorten the interval in dusty environments |
| Intake hose and housing seal | Between air filter assembly and airend | Ensures the intake path is leak-free with no unfiltered air bypass | Check for cracks, ageing and loose clamps; bypass leakage is as harmful as running without an element |
Recommended kit replacement: in dusty sites, replace the air filter, oil filter element and oil separator element together to avoid staggered maintenance intervals and repeated downtime. Schedule the coolant filter and thermostatic valve element on their own cycles.