Description
The Atlas Copco 1616671290 is the OIS H-06 service stage for the C77 oil-injected screw air end. It is the compression element of an Atlas Copco GA15, GA18 or GA22 rotary screw compressor, the part that takes ambient air at the intake and delivers it at working pressure. Everything downstream, from the separator vessel to the aftercooler and the air treatment, works with what this stage produces.
Atlas Copco supplies the 1616671290 through the service channel as a replacement stage. It is classified under rate group S3K, oil-injected screw element, and built in Belgium. Each unit carries its own serial number, so the stage is traced through the supply record and logged against the machine it is fitted to.
Product Overview
A service stage is the compression element supplied for a machine already in the field. It replaces the element fitted on the production line and is built to the same geometry as the original, so fitting one restores the free air delivery and the working pressure the compressor was built for.
The 1616671290 sits in the small industrial power range. Its host machines, the GA15, GA18 and GA22, supply workshops, light manufacturing lines, vehicle service bays and small process plants, where one compressor carries the whole air demand. In that duty the stage decides how much air the site has, and what the site pays in power to get it.
Technical Specifications
The tables below give the identification data recorded for the 1616671290, followed by the dimensions and weight used for handling and transport planning.
Part Identification
| Parameter | Value |
|---|---|
| Service part number | 1616671290 |
| Production part number | 1616671280 |
| Stage designation | OIS H-06 |
| Air end family | C77 |
| Product type | Oil-injected screw service stage |
| Rate group | S3K Oil injected screw, Element |
| Brand | Atlas Copco |
| Country of origin | Belgium |
| Customs tariff code | 8414900090 |
| Reference price | 9,792.41 EUR |
Dimensions and Weight
| Parameter | Value |
|---|---|
| Item length | 50 cm |
| Item width | 37 cm |
| Item height | 33 cm |
| Item weight | 53 kg |
| Order pallet | No |
Part Numbers and Air End Family
1616671290 and 1616671280
Atlas Copco lists this stage under two numbers. The number 1616671280 is the production code, the number recorded against a compressor built with this stage on the line. The number 1616671290 is the service code used when the stage is ordered as a spare. Both numbers identify the same OIS H-06 stage in the C77 air end.
Ordering the service code returns the current revision of the genuine part. The mounting faces, the shaft interface and the oil port positions are unchanged, so a team that reads 1616671280 from an existing machine orders 1616671290 and fits it without any adaptation work.
What C77 and OIS H-06 mean
C77 is the air end family. It is the designation Atlas Copco uses for this class of oil-injected screw element, and it runs through the related parts catalogue, where the C77 outlet housing and the C77 filter element are separate service items.
OIS H-06 is the stage designation. OIS stands for oil-injected screw, the compression principle the stage uses. H-06 identifies the stage size within the family. Knowing both is what separates a correct order from a near miss, because several stages share the C77 family and differ by size.
Host Machines and Duty
The 1616671290 is the service stage for the GA15, GA18 and GA22 oil-injected screw compressors. These machines cover the 15 to 22 kW band in fixed-speed and variable-speed drive, and they are the compressors used in a workshop, a small production cell, a vehicle service bay or a laboratory, where one machine carries the site air demand.
Stage, frame, mount and port differ across the GA15 to GA22 span and across the build years of the same model. The parts list for the machine serial number is the record that names the stage your machine was built with, and it is the reference the parts desk works from.
How the Stage Works
The compression cycle
The 1616671290 holds a male rotor and a female rotor turning in opposite directions inside a machined housing. The rotors do not touch each other or the housing wall at any point in the cycle, and the pair is kept in step by its own geometry rather than by contact.
Air enters through the inlet port and fills the groove between the two rotors. As the rotors turn, the meshing point travels along the rotor length and closes the groove, trapping the air. Continued rotation shortens the pocket and the pressure inside it rises, until the pocket reaches the discharge port and the air leaves for the separator vessel.
Each pocket follows the same path and the cycle repeats continuously. That is what gives the 1616671290 its steady, low-pulsation delivery.
Oil injection and the separation loop
Oil enters the compression chamber through a port in the housing and does three jobs at once. It seals the clearance between the rotors and between each rotor and the housing wall, so compressed air does not leak back towards the inlet. It carries away the heat of compression. It reaches the bearings and the rotor mesh and keeps a lubricating film on every moving surface.
Air and oil leave the 1616671290 together and pass to the separator, where the bulk of the oil is removed and returned to the sump. The clean air goes on to the aftercooler and the outlet. The recovered oil is cooled, filtered and returned to the injection point.
Bearings and shaft sealing
The rotors run on bearings carried in the end covers of the 1616671290. The bearings take the radial load from the gas pressure and the axial load generated as pressure builds along the rotor length, holding rotor position in both directions.
Shaft sealing separates the two circuits at the rotor ends. Oil stays in the bearing and injection circuit, and air stays in the compression chamber. The sealing holds a thin film between the sealing faces and the shaft, so it does not run in metal-to-metal contact.
Ordering the Correct Stage
Two pieces of information lock an order down quickly: the part number and the machine it is going into. The part number is read from the existing stage or from the machine parts list, and reads 1616671290 or the production code 1616671280. The machine is identified by the model and serial number on the compressor nameplate.
Sending both together lets the parts desk confirm that 1616671290 is the right stage in one pass, instead of going back and forth. Where the number on the old stage is worn or missing, the nameplate alone is enough, because the spare parts list for that serial number names the stage.
Sites running more than one GA-class machine keep a short record for each one: model, serial number and stage number. That record turns the next enquiry into a single message with a confirmed answer.
Handling and Installation
Keep the protective caps on the inlet and discharge ports until the moment of fitment. Grit or moisture reaching the rotor faces or the bore scores the rotors on the first start, and the damage cannot be undone.
At 53 kg the 1616671290 is a two-person lift, and it is set down square on its mounting face rather than rolled onto its shaft. The stage measures 50 cm by 37 cm by 33 cm, so it goes through a standard door and onto a bench.
Seat the 1616671290 on its mounting faces, line it up with the inlet and discharge ducting, and torque the fasteners to the values in the compressor manual. Confirm the shaft alignment and the rotation direction before the first start, and fit new seals and gaskets rather than reusing the old ones.
Because the 1616671290 is an oil-injected stage, its bearings run on the compressor’s own oil circuit. Fill the machine with the specified lubricant, check the oil level, and run the compressor unloaded while the discharge temperature, the oil pressure and the vibration at the bearing housings are watched. Re-torque the coupling and mounting bolts after the first running hours.
Service Life, Monitoring and Overhaul
The 1616671290 wears gradually, and the change appears in four readings. Free air delivery falls at the same rated pressure. Discharge temperature rises under the same load and ambient condition. Power drawn per unit of air delivered increases. Vibration and noise at the housing grow at a steady load.
Any one of those readings, taken once, means little. Recorded at a fixed interval they form a trend, and the trend is what turns an unscheduled failure into planned work. Oil analysis adds a second line of evidence, because wear debris in the oil shows up before the vibration reading moves.
When a stage reaches the end of its service life, the choice is between a workshop rebuild and a new stage. A rebuild keeps the original rotors and housing and renews the bearings, seals and gaskets, and it suits a unit with no scoring or pitting on either. A new 1616671290 returns the stage to its original specification in one step. The decision follows a teardown inspection and a clearance measurement by a qualified technician.
FAQ
Is the 1616671290 the same as the 1616671280?
Both numbers identify the same OIS H-06 stage in the C77 air end. The number 1616671280 is the production code recorded when the compressor was built, and 1616671290 is the service code used to order a replacement. Fitment is identical between the two.
Which compressors use the 1616671290?
The 1616671290 is the service stage for the Atlas Copco GA15, GA18 and GA22 oil-injected screw compressors. Stage, frame, mount and port differ across that span and across build years, so the parts list for the machine serial number is the record that confirms the match.
How do I confirm the 1616671290 fits my machine?
Match the number on the existing stage, which reads 1616671290 or the production code 1616671280, then confirm the model and serial number on the compressor nameplate. Send us both and we will confirm the match before you order.
What does C77 mean?
C77 is the air end family Atlas Copco uses for this class of oil-injected screw element. The same family lists the C77 outlet housing and the C77 filter element as separate service items. OIS H-06 is the stage designation inside that family.
Can the stage be rebuilt instead of replaced?
A rebuild keeps the original rotors and housing and renews the bearings, seals and gaskets, and it suits a unit with no scoring or pitting on the rotors or housing. A new 1616671290 returns the stage to its original specification in one step. The decision follows a teardown inspection by a qualified technician.
Omar Al-Farsi –
We changed the stage on our GA18 during a planned service day. The parts desk confirmed 1616671290 against our machine serial number before we paid, so there was no second round of questions. It arrived sealed with the port caps in place and the serial plate intact, and two of us lifted it onto the bench. It seated on the original mounting faces without any adjustment, and the compressor came back to its normal delivery on the first run. We keep the part number and the machine serial number together in the service log now, so the next overhaul starts from a confirmed number.