HELAC ALTERNATIVE
L40-110-M-FT-360-S1-C-H Rotary Actuator
Alternative rotary actuator for the Helac L40-110-M-FT-360-S1-C-H, a heavy-duty 360-degree, foot-mount (FT) helical actuator in the L40-110 class, in the 150 kg weight band. It is listed by Atlas Copco / Epiroc under part number 3128341084 (also written 3128-3410-84) and is associated in the source parts documentation with the Boomer S2 development rig.
Atlas part number
3128341084
Alternative rotary actuator for Helac L40-110-M-FT-360-S1-C-H.
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Independently supplied alternative — not an original Helac or Atlas part. Compatibility is verified before ordering.
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.
L40-110-M-FT-360-S1-C-H
L40 series
| Segment | Field | What it tells you |
|---|---|---|
| L40 | Series | L40 series — frame size and mounting family |
| 110 | Model size | Size 110 — rated drive torque is set by this number (thousand in-lb class in the L/T key) |
| M | Measurement system | Metric system — metric threads, BSPP ports |
| FT | Housing / mounting | Foot mount |
| 360 | Rotation | Standard 360° rotation |
| S1 | Shaft / flanges | Cantilever — shaft flange only (single) |
| C | Valve | Counterbalance valve fitted |
| 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
- L40-110-M-FT-360-S1-C-H
- Original brand
- Helac
- Type
- Rotary actuator
- Rotation
- 360°
- Weight
- 150 kg
- Original part no.
- 3128341084
Equipment reference
Known applications
Part number 3128341084 is recorded against the foot-mount L40-110 360-degree build. The image shows the L40-110 family; the exact foot-mount interface, shaft and ports are confirmed against your actuator nameplate and a drawing before ordering. Rigs in this range can use different turning devices by serial number and position.
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 | 150 kg |
| Cross reference | The L40-110-M-FT-360 is the foot-mount sibling of the rear-flange L40-110-M-RF-360 build (Atlas 3128341070). Mounting interfaces differ between FT and RF, so they are not interchangeable; the mount, rotation and ports are verified against the unit tag before a replacement is supplied. |
| 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 L40 range
Questions
Frequently asked questions
What does the L40-110-M-FT-360-S1-C-H replace?+
It is the model code for a Helac helical rotary actuator providing 360° rotation in the 150 kg class. It is listed by Atlas under part number 3128341084. Our alternative is matched to the same rotation, 150 kg class and mounting interface.
How do I know this fits my machine?+
The same actuator is recorded on the Boomer S2. 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 is Atlas Copco / Epiroc part 3128341084?+
Part 3128341084 is recorded against the Helac L40-110-M-FT-360-S1-C-H, the heavy-duty 360-degree foot-mount actuator in the 150 kg class, associated with the Boomer S2 rig in the source parts documentation. Send your nameplate and we confirm the foot-mount interface, shaft and ports before quoting.
Does 3128341084 interchange with 3128341070 (L40-110-RF-360)?+
Both are 360-degree L40-110 builds, but 3128341084 is the foot-mount (FT) version and 3128341070 is the rear-flange (RF) version. The mounting faces and bolt patterns differ, so they are not drop-in interchangeable; confirm the FT or RF mount on your tag before ordering.
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