IDENTIFICATION

How to Identify Your Helac Actuator: Model Tag, Serial Number & Code Breakdown

A Helac rotary actuator is identified by the model code on its silver plastic tag, usually fixed to the housing. If the tag is missing or worn, read the stamped numbers on the body and measure the outside diameter, shaft, and mounting pattern. The model code states the series, torque size, thread/port system, mounting, rotation angle, bearing option, valve option and seal compound in a fixed order.

Last reviewed: October 2026

Search by part number or model code

Paste an OEM part number (JLG, Genie), a Helac model code, or a brand such as HKS, Moveco or Sungji. Results link straight to the matching reference page; if nothing comes back, send the number and we check it against the factory records.

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Browse by series

11 models

L10 Series

Compact helical actuators for small to mid-size drill rigs and bolters.

9 models

L20 Series

Mid-size actuators including compound-angle builds for mid-size equipment.

18 models

L30 Series

Large flange and round-flange actuators for heavy-duty rotation.

Heavy-duty & specialty Helac-family actuators

L40 · HTX · HP

6 models

Larger, splined-shaft and specialty Helac-family actuators for the biggest rotation duties, drill rigs and aerial platforms. Each series has its own mounting interface and torque envelope — they are not equivalent to the L30 series.

L40 HTX HP

Other Helac series & variants

T-series straddle

4 models

Dual-spline, straddle-mount T-series actuators for mid-duty rotation. These builds have a different housing and output-shaft arrangement than the L-series and are selected on their own mounting drawings.

T20-25 T30-27 T20-45 T20-60

Three Ways to Identify Your Actuator

Read the tag

Locate the silver plastic tag on the housing. The full model code is printed here and is the fastest identification method.

Check stamped numbers

If the tag is missing, look for stamped numbers on the body. These usually show the series and size, sometimes with a manufacturing date.

Measure the unit

Measure outside diameter, shaft diameter, mounting bolt pattern, and rotation angle. Send the numbers and we narrow down the series.

Helac Model Code Breakdown

The standard L- and T-series code is read from left to right. Each segment tells us something about the replacement we need to match. Heavy-duty HP units and OEM-specific tags can deviate from this layout, so the tag photo always takes priority.

Position	Meaning	Example values
1 · Series	Actuator series	L10, L20, L30, L40, T20 (HP/T30 follow their own key)
2 · Model / torque	Model size = rated drive torque in thousand in-lb	3.0, 5.5, 9.5, 17, 25, 42, 65, 110
3 · Measurement system	E = English system (SAE/UNF threads, SAE ports); M = Metric system (metric threads, BSPP ports); ES or MS = Custom Design (special OEM build — not a standard E/M unit)	E · M · ES / MS (older tags may use S for special)
4 · Housing / mounting	Housing mounting configuration (varies by series)	RF rear flange · FT foot mount · FF front flange (L30) · RM/RL rail (L40)
5 · Rotation	Standard 180 or 360 per HY34-1001. Older L30 catalogs list 210° only for the specific L30-380 model, not for the whole L30 series. Special rotations are written with a slash: base/final, e.g. 180/90, 180/120 — an internal stop tube sets the final angle, in 10° increments	180 · 360 · 180/90 (special) · 210 (L30-380 only, older catalog)
6 · Shaft / flanges	Shaft & end-cap flange configuration for the load path	S1 = cantilever (shaft flange only) · S2 = straddle (shaft + end-cap flanges)
7 · Valve	Counterbalance-valve option (HY34-1001: C = counterbalance valve, 0 = no valve, V = valve ready). The character used for "no valve" varies by brand and series — read it from the specific OEM model record rather than assuming one spelling	C = counterbalance valve · 0 = no valve · V = valve ready (pad machined, no valve fitted)
8 · Seals & bearings	Seal and bearing package	H = standard seals & bearings · S = special seals & bearings (exact compound per tag/drawing)

Example codes — structure only

L10-5.5-M-RF-360-S1-[valve code]-H

L10 series · 5.5 model (5,500 in-lb) · M metric system (BSPP ports) · RF rear flange · 360° standard rotation · S1 cantilever shaft flange · [valve code] no valve · H standard seals & bearings.

L10-25-E-RF-180/90-S1-[valve code]-H

Same convention, but 180/90 is a special rotation: a standard actuator fitted with an internal stop tube, where 90° is the final limited angle. Special rotations are available in 10° increments and are confirmed against the tag/drawing.

Both codes above are structure demonstrations only — they are not orderable part numbers. The valve segment is written [valve code] because the character differs by brand and series; read it from the specific OEM model record, not from this guide.

This is a simplified reading guide for the standard Parker-Helac L/T ordering convention (catalog HY34-1001 and the series ordering pages). It is not a claim that every unit has exactly eight segments: custom builds marked ES or MS, special seal/bearing packages marked S, and special rotations can differ; HP and other series may use a different key. Final configuration and compatibility are confirmed against the unit nameplate, the mounting drawing and the actual application — a similar torque rating alone does not confirm a direct replacement. Send a tag photo and we verify the exact build with you.

Serial Numbers and Manufacturing Date

Stamped serial numbers help confirm the production batch and sometimes the manufacturing date. They are useful when the model tag is partially legible or when verifying whether a unit belongs to an OEM-specific revision.

Always include a photo of any stamped numbers along with the tag photo so we can cross check against production records.

What to Photograph for an Inquiry

1. Tag close-up

Clear, in-focus photo of the model code and serial number.

2. Mounting face

Shows bolt pattern and pilot diameter.

3. Shaft end

Shows shaft diameter, keyway, or spline detail.

4. Machine nameplate

Helps confirm OEM part number and application.

FREE IDENTIFICATION

Send for Free Identification

Send the model code, OEM part number, and photos. We identify the exact series and confirm the replacement match before you order.

Or email directly: hm@hmhydraulics.com

Related Guides

Rotary Actuator Types

Helical, rack-and-pinion and vane designs compared.

Cross-Reference Guide

Match OEM part numbers to the right replacement.

Troubleshooting Guide

Diagnose drift, weak torque, leaks and noise.

Questions

Frequently asked questions

What if the Helac tag is missing?+

If the plastic tag is missing or unreadable, look for stamped numbers on the housing and measure the outside diameter, shaft diameter, mounting pattern, and rotation angle. Send us clear photos and we identify the series.

Where is the model tag located?+

The silver plastic tag is usually riveted or glued to the side of the actuator housing, near the valve ports.

Can I identify the actuator from the OEM part number alone?+

Often yes, because OEM part numbers map back to Helac model codes. We can cross-reference the OEM number and confirm the replacement match.

What photos should I send for identification?+

Send a close-up of the tag, a clear view of the mounting face, the shaft end, and the machine nameplate. These four photos cover the data we need most.

Do the stamped numbers include the full model code?+

Stamped numbers may show only the series and size. The full configuration—rotation angle, valve, and mounting—is usually only on the plastic tag.

Helac® and all OEM names are trademarks of their respective owners. HM Hydraulics is an independent manufacturer and is not affiliated with, sponsored by, or endorsed by Helac, Parker, or any listed OEM. Part numbers and model codes are used solely for identification and compatibility purposes.