Description
The 1616710781 is the OFT E-11 oil-free tooth element, a compression stage from the compact end of the Atlas Copco oil-free range. Its family is a distinct branch of that range: where the OFS mark identifies the oil-free screw elements, OFT identifies the oil-free tooth type, whose intermeshing tooth profiles do the compression work in a chamber that no oil ever enters. The element measures 40 x 29 x 30 cm and weighs 39 kg, and it carries the full compression duty of the machine it serves, so its condition shows up directly in delivered pressure, power draw and air quality.
This page records the identification and physical data for the 1616710781, explains what the tooth-type oil-free principle means in practice, and follows the renewal from the first wear signals through ordering and fitting. It is written for the maintenance planner and the parts buyer who need the whole picture in one place, and the ordering reference to carry through all of it is the 1616710781 itself.

What OFT E-11 Stands For
OFT is the Atlas Copco family mark for Oil-Free Tooth elements. The oil-free range is organized by marks, and the letter after OFT separates the tooth type from the screw type within the same oil-free family. E-11 then identifies the size class, so the designation places the 1616710781 both by family and by size before the ordering number is read at all. The element carries both identifiers: OFT E-11 on the documentation, the complete number on the element plate.
For purchasing, the complete number is the reference that counts. Quotations, order confirmations and the parts documentation all key on the 1616710781, and quoting it in the first message leaves the designation to do what it is good at — describing the component — while the number does what it is good at: selecting the exact part. An enquiry that carries the full number arrives at the parts desk already identified.
The plate on the element is the anchor for all of this. A clear photograph of the plate, taken while the machine is open for routine service, records the complete 1616710781 reference together with the serial, and those two lines are everything the parts desk needs to prepare the next quotation. The photograph costs nothing at the time and saves the next planner a round of identification.
Technical Specifications
The tables below list the data recorded for the 1616710781 as supplied through the service channel.
Part Identification
| Parameter | Value |
|---|---|
| Item number | 1616710781 |
| Description | OFT E-11 |
| Product group | Oil-free tooth element |
| Country of origin | Belgium |
| Tariff code | 8414900090 |
| Serialized | Yes |
Dimensions and Weight
| Parameter | Value |
|---|---|
| Length | 40 cm |
| Width | 29 cm |
| Height | 30 cm |
| Weight | 39 kg |
Each 1616710781 leaves the factory serialized, and the number on the plate ties the physical unit to its documentation through installation and every service event after it. The serial and the 1616710781 on the plate together identify the unit beyond doubt. Keeping both with the machine’s maintenance file keeps the element’s history readable: the file then states what is fitted, when it went in and what was supplied with it, which is exactly what the next renewal planner wants to find.

The Oil-Free Tooth Principle
The defining property of the OFT family is the same as for every Atlas Copco oil-free element: the compression chamber stays dry. No oil is injected at any point in the cycle, so the air that leaves the 1616710781 is the air that entered it, compressed but never wetted with lubricant. What separates the tooth type from the screw type is the geometry that does the work: instead of helical rotor lobes, compression is performed by intermeshing tooth profiles, machined into the rotors and running against each other across a controlled non-contact gap.
That gap is where the design concentrates its engineering. The tooth flanks carry an anti-friction coating, so the profiles run close together without touching, and the lubricated components — bearings and shaft seals — sit on the oil side of the chamber boundary, with the seals holding the line between the two sides. In the 1616710781 that arrangement is delivered factory-set, and it is the arrangement every renewal restores. The result is a stage that keeps lubrication entirely outside the air path while the tooth profiles inside it hold the compression clearances that set the element’s efficiency.
For the maintenance planner, the practical meaning is straightforward. The surfaces that wear are inside the chamber — the coating on the tooth flanks and the bearing sets behind them — and they are renewed with the element as a whole, not adjusted in place. When the 1616710781 goes in, the dry chamber, the coated profiles and the oil-side boundary are all restored together in one factory-set assembly.

Air Quality at the Compact End of the Range
Atlas Copco oil-free compressors are built for air classified under ISO 8573-1 Class 0, the strictest oil-content class in the standard, and the element is the component that holds that classification in service. The tooth-type elements serve the compact end of the oil-free range — the small and mid-power machines — where a full-size oil-free plant room would be more installation than the duty calls for, but the process still refuses oil carryover.
The applications follow from that combination. Laboratories, food and beverage lines, pharmaceutical production and electronics manufacturing all have points of use that need clean air without a large-format installation behind them, and the tooth-type oil-free element — the 1616710781 among them — is what makes those machines possible. When the element is renewed, the air-quality boundary the process was designed around is restored with it; the element is not just an output part but the part that keeps the classification honest.
Size does not soften the classification. The compact format of the 1616710781 carries the same dry-chamber discipline as the large screw stages: coating on the working profiles, seals between the oil side and the air side, and no injected oil anywhere in the cycle. A point of use fed by a tooth-type element holds the same air-quality argument as one fed by a large-format installation, because the chamber — not the machine size — decides what the air contains.

Wear Signals and the Renewal Decision
An element wears gradually, and the operating data moves before anything breaks. Free air delivery slips against the same power input. Specific energy climbs, so the machine pays more kilowatt-hours for each cubic meter of air. Discharge temperature drifts upward as the internal clearances begin to leak, and noise or vibration at the stage sharpens as the bearing clearances grow. Every one of these readings has alternative causes in the surrounding system, so the coolers and filters are ruled out first and the 1616710781 is charged with the fault only when the readings point its way.
The trend line is the evidence that settles it. A slow climb across months of logs tells one story; a step change after a cooler blockage tells another, and the log separates the two. When the trend points at the stage, the 1616710781 goes on order while the planned window is being set, and both are ready together. Running a worn element to the end of its life does not end neatly — internal contact in a dry chamber finishes the profiles for good, and the element comes out as scrap rather than as a rebuild candidate. Renewing the 1616710781 on condition, inside a planned service window, keeps the timing in the hands of the maintenance calendar and restores rated delivery in one operation.
Handling and Fitting
At 39 kg the 1616710781 stays on the practical side of handling: a pallet truck to the machine, a shop hoist or a second pair of hands for the final set, and no crane arrangement anywhere in the plan. The new element stays crated until it stands at the machine, and the port caps stay on until connection so nothing enters the chamber. Mounting faces are cleaned, fastener torques follow the values in the compressor manual, and the serial numbers of the old and new elements go into the maintenance record, with the 1616710781 reference recorded alongside each serial, before the machine is closed up.
Fitted this way, the 1616710781 exchange fits inside a scheduled service stop. The element goes in as one complete assembly with nothing to build out on site, so the time in the window is spent on connections and checks rather than on assembly work — a short, controlled job with a clean paper trail at the end of it.
Ordering the Correct Element
Two details close the identification: the part number and the machine. The 1616710781 is read from the plate on the old element, from the machine parts list or from a previous quotation, and the compressor is identified by the model and serial number on its nameplate. Send the pair together and the match is confirmed in one pass, without a chain of follow-up questions.
Where the plate on the old element has worn past reading, the nameplate details still identify the machine, and the parts documentation for that serial carries the element reference. Either route ends in the same place: the correct 1616710781 on order, the identification already settled, and the changeover scheduled into the window the maintenance team has set.

FAQ
What does OFT E-11 stand for?
OFT is the Atlas Copco family mark for Oil-Free Tooth elements — the tooth-type branch of the oil-free range, alongside the OFS screw type — and E-11 identifies the size class. The complete ordering reference is 1616710781, and that number is what identifies the part in quotations, order confirmations and the parts documentation.
How is a tooth element different from a screw element?
Both are oil-free stages with a dry compression chamber; the difference is geometry. A screw element compresses with helical rotor lobes, while the tooth type compresses with intermeshing tooth profiles running across a coated, non-contact gap. The family marks OFS and OFT keep the two apart at a glance, and the complete number — for this element the 1616710781 — identifies the exact unit to order.
How do I confirm the 1616710781 matches my machine?
Read the number from the plate on the element being replaced, or take the model and serial number from the compressor nameplate. Send either or both, and the 1616710781 is checked against the parts documentation before the order is placed. One message with those details is enough to close the identification.
What handling does a 39 kg element need?
A pallet truck to the machine and a shop hoist or a second pair of hands for the final positioning — no crane and no heavy rigging. The 1616710781 stays crated until it stands at the machine, and the whole exchange fits inside a scheduled service stop.
What happens if a worn element stays in service?
Delivery and efficiency fall first, and the machine pays more energy for the same air. In a dry chamber, internal contact finishes the tooth profiles for good, and an element at that stage is replaced rather than rebuilt. Renewing the 1616710781 on condition avoids the unscheduled stop and restores rated output in one planned operation.
Is the element supplied as a complete assembly?
Yes. The 1616710781 arrives as one factory-set unit with the coated tooth profiles, bearings and shaft seals in place, so the renewal is an assembly exchange with no on-site internals work. The unit is serialized, and the plate number links it to its documentation through installation and service.















Yusuf Demir –
The old element in our oil-free unit had been drifting on delivery for months, so we quoted the 1616710781 against the plate number and had the match confirmed with the machine details in the same message. The element arrived crated, went in during the scheduled service stop, and the compressor came back to its rated delivery and a stable discharge temperature. For a stage of this size the whole exchange stayed simple: two technicians, the shop hoist and one morning.