HELAC ALTERNATIVE
L10-5.5-E-RF-360-S1-O-H Rotary Actuator
Alternative rotary actuator for the Helac L10-5.5-E-RF-360-S1-O-H, a continuous 360-degree helical actuator listed by Atlas under part number 3128309281, in the 21 kg class.
Atlas part number
3128309281
Alternative rotary actuator for Helac L10-5.5-E-RF-360-S1-O-H.
Specifying a new program? Talk to our engineering team →
Independently supplied alternative — not an original Helac or Atlas, Sandvik part. Compatibility is verified before ordering.
HM Model Reference
HMR3-060 — HM's closest model in the 620 Nm class
This reference sits in the 620 Nm class. The closest HM model is HMR3-060 — Helical, L10-style compact front flange — matched on torque class only. The left column repeats what this reference's own record states, reproduced as published; the right column is HM's own rating. The table shows what carries over and what still has to be checked on your unit.
Original
L10-5.5-E-RF-360-S1-O-H
HM Model Reference
HMR3-060
Rated torque
Rated pressure
Rotation
Mounting
Output shaft
Valve options
| Original L10-5.5-E-RF-360-S1-O-H | HM HMR3-060 | |
|---|---|---|
| Rated driving torque | Not verified | 620 Nm |
| Rated pressure | Not verified | 210 bar |
| Rotation | 360° | 180° / 360°; stop at 90° available |
| Mounting | Not verified — confirm on unit | FF — Front flange (standard) |
| Output shaft | Not verified — confirm on unit | 1F — Single flange shaft (standard) |
| Valve options | Not verified — confirm on unit | NV / CB / CS |
| Ordering pattern | Not applicable | HMR3-{spec}-{angle}-FF-1F-{valve} |
Left column: this reference's own published figures, reproduced as recorded. Any field the record does not establish is marked “Not verified” and is never filled from HM data. Right column: HM's own rating at HM's stated pressure. Confirm both against the unit nameplate and mounting drawing before ordering.
What carries over
- HM torque class (620 Nm) at HM's 210 bar rating.
- Helical, L10-style compact front flange architecture.
- Rotation: 180/360° available on the HMR3 series. A 180/90 code is a 180° unit with the stop set at 90°, not a separate build.
What has to be verified
- Shaft / output flange interface and spline.
- Mounting bolt pattern and pilot register.
- Port size and position, plus valve arrangement (NV / CB / CS).
- Overall envelope and tie-rod clearance.
Comparable performance based on rated torque class for engineering comparison. The mounting interface must be confirmed by our engineering team before quotation.
Same base, other builds
Other configurations of this size
One base size is built in several mountings, angles and valve arrangements. If your unit carries a different code from the one on this page, start from the closest build below.
Code anatomy
What each part of this code means
Every segment below is read from the manufacturer’s published ordering key. Where a segment is not published, we say so instead of guessing — those are the ones to confirm from the tag or the drawing before ordering.
L10-5.5-E-RF-360-S1-O-H
L10 series
| Segment | Field | What it tells you |
|---|---|---|
| L10 | Series | L10 series — frame size and mounting family |
| 5.5 | Model size | Size 5.5 — rated drive torque is set by this number (thousand in-lb class in the L/T key) |
| E | Measurement system | English system — SAE/UNF threads, SAE ports |
| RF | Housing / mounting | Rear flange |
| 360 | Rotation | Standard 360° rotation |
| S1 | Shaft / flanges | Cantilever — shaft flange only (single) |
| O | Valve | No valve |
| H | Seals and bearings | Standard seals and bearings |
Full ordering key and how to read a tag: identifying a rotary actuator.
What the 360° sweep changes on this build
A full-turn build: the output sweeps a complete revolution. The hose loop and its clamping have to survive the whole sweep, which is why a full-turn unit is checked as a hose-routing question as well as a torque question.
- Check the hose loop clears the housing through the full revolution, not just at the rest position.
- Confirm the duty actually needs a complete turn — a half-turn build of the same size is the usual choice where it does not.
- Rotation stops, if the machine has them, sit outside the actuator and still have to be checked.
When this sweep is the right build
- Duties that genuinely index through a full revolution — rod handling, turret positioning, continuous swing.
- Linkages where the return path is part of the cycle rather than a reversal of the same half turn.
- Machines already built around a full-turn hose loop, where a half-turn unit would leave the routing over-travelled.
Confirming the sweep on the machine
- Turn the linkage through a full revolution by hand and watch the hose loop — a unit that binds at three quarters of a turn is a routing problem, not a torque problem.
- Check whether the machine has an external rotation stop; if it does, the sweep on the tag is not the limit the linkage actually uses.
How the sweep sits in the order code
The sweep is the fifth segment of the code. Going to the half-turn build of the same size changes that segment and the internal stop tube; flange, shaft and valve stay as they are. Where a machine only needs two positions, the half-turn build is the shorter hose route and the smaller envelope.
Where these two builds get mixed up
- A full-turn unit is sometimes quoted where the linkage only swings half a turn, which over-travels the hose loop for no benefit.
- If a full-turn unit will not pass a quarter or half turn under load, the cause is usually hose routing or an external stop, not the actuator.
At a glance
Quick reference
- Original model
- L10-5.5-E-RF-360-S1-O-H
- Original brand
- Helac
- Type
- Rotary actuator
- Rotation
- 360°
- Weight
- 21 kg
- Original part no.
- 3128309281
Equipment reference
Known applications
Based on equipment records, this actuator is associated with the following Atlas Boltec drill rigs. Confirmation against your machine build plate is recommended.
If your machine is not listed, send the full model and serial number — other builds may use the same actuator.
Confirmed data only
Technical specifications
| Product type | Hydraulic rotary actuator |
|---|---|
| Rotation angle | 360° |
| Unit weight | 21 kg |
| Further data | Torque, pressure, port and mounting dimensions are shared with the engineering drawing on request. |
HM alternative model — confirmed on inquiry. Send us your original model number, part number or machine details and we confirm the matching configuration, specifications and compatibility, then quote. The exact ordering code — rotation, output and valve arrangement — is confirmed against your unit and is not published online.
Other models in the Helac L10 range
Showing 8 of 10 other models in this range.
Questions
Frequently asked questions
What does the L10-5.5-E-RF-360-S1-O-H replace?+
It is the model code for a Helac helical rotary actuator providing 360° rotation in the 21 kg class. It is listed by Atlas, Sandvik under part number 3128309281. Our alternative is matched to the same rotation, 21 kg class and mounting interface.
How do I know this fits my machine?+
The same actuator is recorded on the Boltec 235, Boltec 235h, Boltec Lc, Boltec Md. Before quoting we confirm the mounting face, port position and rotation against the tag and a photo of your unit, so the replacement matches your exact build.
What other order codes are available in this same series?+
Other catalog configurations of the same actuator family include: L10-5.5-E-RF-360-S1-C-H. These are complete Helac order codes differing in rotation angle, ports, valve or mounting/flange arrangement; they are not interchangeable with the configuration shown on this page. Send the exact code on your unit tag or a mounting drawing and we confirm the matching build before quoting.
Is part number 3128309281 the same actuator on the Boltec 235?+
Yes. On the Atlas Copco / Epiroc Boltec 235, 235h, Lc and Md drill rigs the 360-degree rotary actuator is supplied under part number 3128309281, corresponding to the Helac L10-5.5-E-RF-360-S1-O-H configuration (360-degree rotation, round-flange mount). Before ordering we confirm the mounting face, port position and rotation against the tag and a photo or drawing of your unit.
Why is the exact HM model and price not shown?+
We confirm the HM model per inquiry after verifying the interface and operating parameters with you. This avoids shipping a part that looks right by model name but differs in mounting or rotation. Price is provided with that confirmed quote.
Request a check
Looking for an alternative to this model?
Send us the original model number, part number, machine model or a drawing. We check the available option and confirm specifications and compatibility for you.
- Original model / part number
- Machine brand & model
- Quantity & annual demand
- Mounting photo or drawing (if available)
Or email directly: hm@hmhydraulics.com