SUNGJI SOURCING
SRC-125 Rotary Actuator
The Sungji SRC-125 is a helical hydraulic rotary actuator from Sungji (SJH, Korea), part of the SRC family in the L30 size class and rated at about 2824.3 Nm output torque at 210 bar. Sungji lists the SRC series at 180-degree rotation only, with no 360-degree build in this family. In the controlled cross-reference it sits in the ~2820 Nm torque class together with: Helac L30-25 (~2821 Nm); HKS M-DA-H-F5 125 / M-DA-H-F10 125 (~2820 Nm); Moveco RR40 (~2821 Nm). These are same-torque-class engineering references only. HM Hydraulics provides technical selection support and sourcing / alternative-supply service for this reference. We do not hold it as a stocked SKU and do not promise stock, lead time or confirmed availability; configuration, mounting dimensions and drawings are checked on request against your actuator nameplate before any quotation.
Sungji SRC series helical rotary actuator
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Independently sourced / alternative-supply service — not represented as an original Sungji part. Interchangeability is verified against your unit and drawing before ordering.
HM equivalent
HMR4-280 — the same 2,820 Nm torque class
This reference sits in the 2,820 Nm class. The closest HM model is HMR4-280 — Helical, L30-style heavy-duty — in the same torque class. The table shows what carries over and what still has to be checked on your unit.
Original
SRC-125
HM equivalent
HMR4-280
Rated torque
Rated pressure
Rotation
Mounting
Output shaft
Valve options
| Original SRC-125 | HM HMR4-280 | |
|---|---|---|
| Rated driving torque | 2,820 Nm * | 2,820 Nm |
| Rated pressure | 210 bar * | 210 bar |
| Rotation | 180° | 180° / 360°; stop at 90° available |
| Mounting | Per original build — confirm on unit | FT — Foot / FF — Front flange / RF — Rear flange |
| Output shaft | Per original build — confirm on unit | 1F — Single flange shaft / 2F — Double flange shaft |
| Valve options | Per original build — confirm on unit | NV / CB / CS |
| Ordering pattern | — | HMR4-{spec}-{angle}-{mount}-{output}-{valve} |
* Original-side figures are the manufacturer's catalogue values for this torque class. Confirm against the unit nameplate before ordering.
What carries over
- Torque class and rated pressure (210 bar).
- Helical, L30-style heavy-duty architecture.
- Rotation: 180/360° available on the HMR4 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.
What the 180° sweep changes on this build
A half-turn build: the output travels 180° between two end stops. The sweep is set by the internal stop tube, so a 180° unit cannot be turned into a 360° one by changing the valve or the porting — it is a different internal assembly.
- Two positions, 180° apart — confirm the linkage does not rely on an intermediate stop.
- Hoses only travel half a turn, so a short service loop is normally enough.
- If the duty is a tilt or a quarter-turn swing, this is the sweep the linkage was designed around.
When this sweep is the right build
- Tilt and positioning linkages that only need two end positions — a bucket tilt, a boom offset, a chute flap.
- Machines where the hose run is tight: half a turn needs a much shorter service loop than a full one.
- Where a mid-position stop is not part of the function, so the two end stops are the whole travel.
Confirming the sweep on the machine
- Swing the linkage by hand to both end stops and check the travel is a clean half turn with no mid-travel detent.
- Read the stop positions off the mounting drawing rather than counting turns of the output.
How the sweep sits in the order code
The sweep is the fifth segment of the code. Ordering the same size in the other sweep changes that segment and the internal stop tube behind it; the flange pattern, the shaft end and the valve selection do not change with it. That is why a half-turn build and a full-turn build of one size are quoted as two builds rather than one with an option.
Where these two builds get mixed up
- A half-turn unit is sometimes quoted against a full-turn drawing because the size and mounting match — the sweep is the field that gets dropped in the enquiry.
- A half-turn unit cannot be re-stopped to a full turn in service; if the machine needs more travel, it needs the other build.
Same torque class
Other references our customers compare with this one
These builds sit in the same torque class as the unit on this page. Same class does not mean interchangeable — the mounting interface, shaft and port arrangement are confirmed against your tag or drawing before quoting.
At a glance
Quick reference
- Original model
- SRC-125
- Original brand
- Sungji
- Type
- Rotary actuator
- Rotation
- 180°
- Rated torque
- 2824.3 Nm
- Weight
- 47 kg @180°
Confirmed data only
Technical specifications
| Product type | Hydraulic rotary actuator |
|---|---|
| Rotation angle | 180° |
| Rated torque | 2824.3 Nm |
| Unit weight | 47 kg @180° |
| Cross reference | All references below are engineering cross-references by torque class from HM's controlled multi-brand database; they are not validated substitutions. Same torque class (comparable rated output; independent housing and mounting designs - do not assume matching dimensions): Helac L30-25 (~2821 Nm); HKS M-DA-H-F5 125 / M-DA-H-F10 125 (~2820 Nm); Moveco RR40 (~2821 Nm). HM has no supply-verified interchange record for any of these pairings, so the highest claim we make is 'same torque class / comparable'; nothing is presented as a verified interchangeable unit. |
| 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.
Questions
Frequently asked questions
What does the SRC-125 replace?+
It is the original Sungji model code for a helical hydraulic rotary actuator providing 180° rotation. HM provides sourcing and alternative-supply support for this reference; it is not assumed to be an original Sungji part or a pre-verified interchangeable unit, and the configuration is confirmed against your actuator nameplate and drawing before we quote. HM can source or arrange alternative supply for this reference; mounting dimensions, shaft, ports and the exact configuration are checked against your unit and drawing before any alternative is recommended.
What does the Sungji code SRC-125 mean, and can HM source it?+
The short code gives the family and bore size; a full ordering code adds rotation, valve/port, mounting, shaft cover and seal/standard segments, so the nameplate tells us the exact build to quote. HM can source or arrange alternative supply for this standard build after confirming the exact configuration from your nameplate; we do not hold it as stock or promise lead time.
Does Sungji list a 360-degree build in the SRC family?+
No. The Sungji catalogue lists the SRC series at 180-degree rotation only, so there is no 360-degree SRC build. If your unit is a 360-degree actuator, send the nameplate and we check the equivalent in another Sungji family or advise the alternative-supply option.
Is the SRC-125 a one-to-one replacement for the Helac / HKS / Moveco unit in the same torque class?+
They are same-torque-class engineering references only; housings, mounts and published moment figures differ. We do not claim a verified drop-in or guaranteed compatibility without checking the drawing, mounting dimensions, shaft and ports against your unit.
What information does HM need before quoting this actuator?+
Send us the actuator nameplate (brand, full model code, rotation, mounting, shaft and port details) and, if available, a mounting drawing. HM then confirms the exact configuration and advises the available sourcing or alternative-supply option. Mounting dimensions and drawings are provided on request only.
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 sourcing
Need a source for SRC-125?
Send the original Sungji model number, the Sandvik / OEM part number, machine details or a mounting drawing. We confirm the configuration and advise the available sourcing or alternative-supply option before quoting.
- Original model / part number
- Machine brand & model
- Quantity & annual demand
- Mounting photo or drawing (if available)
Or email directly: hm@hmhydraulics.com