This model is discontinued
AirTAC has phased out the SU series. You can still order this code here: we ship the direct replacement B04-SAUD40X125S, with the same bore, stroke, output force, port and mounting, so it fits the same application. The SAU replacement uses the same profile body, bore, stroke, force and SC-series mounting. It moves to the current CMSG / DMSG / EMSG sensor switches (the SU used CS1-B / DS1-B) and adds the SAUF valve-integrated option.
Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S
The AirTAC Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S is a double-acting profile-type standard cylinder with a Ø40mm bore and 125mm stroke, 1/4" air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the B04-SAUD40X125S, which matches its bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke125 mm
- Port size1/4"
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → B04-SAUD40X125S
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S
The AirTAC B04-SUD40X125S is a double-acting, double-rod profile cylinder where the B04- prefix designates it as a construction-machinery dedicated variant of the base SUD40X125S, mechanically identical in every spec. A rod exits both ends on a single piston, meaning both faces use the rod-side area and push/pull force is equal both ways at 528 N @0.5 MPa, 739 N @0.7 MPa, and 950 N @0.9 MPa. The extruded aluminium profile barrel is more compact than an ISO 15552 cylinder of the same bore. This legacy model is discontinued and the direct replacement is the SAUD40X125S.
Because the rear rod can carry a sensor cam or drive a second tool simultaneously, double-rod designs offer excellent anti-rotation stability for heavy-equipment builders. This unit features a 16 mm rod, M12x1.25 rod thread, 1/4" port, and 21 mm adjustable air cushions at each end. Note that the air cushion only decelerates near stroke end; it does not hold loads on air loss, so an external rod lock is required for held loads.
Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S Technical Specifications
| Model | Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S |
|---|---|
| Series | SU profile-type cylinder (discontinued) |
| Replacement | B04-SAUD40X125S |
| Bore size | Ø40 mm |
| Stroke | 125 mm |
| Acting type | Double acting |
| Port size | 1/4" |
| Rod thread | M12×1.25 |
| Fluid | Air (filtered by 40µm element) |
|---|---|
| Operating pressure | 0.15 – 1.0 MPa |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Cushion | Adjustable, 21 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SU datasheet (now discontinued). The B04-SAUD40X125S carries the same ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
The B04-SAUD40X125S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S
| SU | Profile-type standard cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×125 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Legacy SU-family variants: SUD (double rod), SUJ (adjustable stroke) — each maps to its SAU equivalent (SUD→SAUD, SUJ→SAUJ). The current SAU line adds the SAUF valve-integrated option.
Where the Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S Is Used
Excavator Panel Pusher
Drives cabin panels on construction machinery using equal both-ways force, relying on the dual rods to prevent binding under off-center loads.
Heavy-Equipment Clamp
Actuates a gripping jaw on earthmoving assembly lines where the rear rod simultaneously moves a secondary release mechanism.
Slew Drive Stopper
Acts as a hard stop for rotating heavy-equipment platforms, using adjustable 21 mm cushions to decelerate high-speed impacts safely.
Replacing the Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S with the B04-SAUD40X125S
To replace the discontinued B04-SUD40X125S, order the direct replacement SAUD40X125S, which matches the 40 mm bore, 125 mm stroke, 1/4" port, and FA/LB mounting exactly. When sizing both ways, verify the equal force (528 N @0.5 MPa) meets your needs, or step to neighbouring bores (32 mm or 50 mm) for different loads. A double rod is right when you need anti-rotation stability or dual-tool driving. The -S magnet means this SUD used legacy CS1-B/DS1-B switches; the SAUD replacement uses current CMSG/DMSG/EMSG sensors. For strokes >=300 mm, confirm the side-load line to prevent guide failure.
Replacement checklist
- ✓ Same bore / stroke → B04-SAUD40X125S
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S): sensor family CS1-B → CMSG
- ✓ Mounting reused (FA/FB/CA/CB/LB)
- ✓ Need a built-in valve? → SAUF
Airtac B04-SUD Construction Machinery Special Standard Cylinder B04-SUD40X125S FAQ
Yes, the B04-SUD40X125S is discontinued. The direct replacement is the SAUD40X125S. The B04- prefix simply marks it as a construction-machinery dedicated variant of the SUD40X125S, so the SAUD matches the 40 mm bore, 125 mm stroke, force, and 1/4" port perfectly. You only need to upgrade the sensors from legacy CS1-B/DS1-B to current CMSG/DMSG/EMSG.
Because it is a double-rod cylinder, force is equal both ways: 528 N @0.5 MPa, 739 N @0.7 MPa, and 950 N @0.9 MPa. The bore is 40 mm with a 1/4" port. Remember that the air cushion only decelerates; it does not hold loads without live air.
Related AirTAC SAU Cylinders
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