This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X400CB, with the same bore, stroke, output force, port and mounting, so it fits the same application. The SAI replacement keeps the same ISO 15552 mounting interface, bore, stroke, output force and accessories, so it drops straight into existing fixtures. It is the current-production version of this cylinder with an upgraded piston seal.
Airtac SI125 Standard Cylinder SI125X400CB
The AirTAC SI125 Standard Cylinder SI125X400CB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 400mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X400CB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke400 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X400CB
- 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 SI125 Standard Cylinder SI125X400CB
The AirTAC SI125X400CB is a discontinued double-acting ISO 15552 profile cylinder featuring a 125 mm bore, 400 mm stroke, and a CB clevis mount. Generating a push force of 6136 N at 0.5 MPa, it utilizes a G1/2 port and a 32 mm piston rod. Because this legacy SI unit is end-of-life, you should order the direct replacement: the SAI125X400CB.
The SAI125X400CB maintains the same ISO 15552 mounting interface, bore, stroke, and force ratings, fitting existing fixtures perfectly. It upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure and longer life. Note this non-magnetic SKU cannot accept a sensor.
Airtac SI125 Standard Cylinder SI125X400CB Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X400CB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X400CB |
| Bore size | Ø125 mm |
| Stroke | 400 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2.0 |
| 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 – 500 mm/s |
| Cushion | Adjustable, 40 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI125X400CB carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
The SAI125X400CB produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI125 Standard Cylinder SI125X400CB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×400 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Legacy SI-family variants: SID (double rod), SIJ (adjustable stroke) — each maps to its SAI equivalent (SID→SAID, SIJ→SAIJ). Rod material: carbon steel (blank) / SUS420J2 (A) / SUS304 (B).
Where the Airtac SI125 Standard Cylinder SI125X400CB Is Used
Heavy Stamping Press
Drives large heavy-duty stamping dies requiring substantial push force over a 400 mm travel distance.
Pallet Lifting Arm
Actuates robust lifting mechanisms on automated palletizers, handling loads near the 313 kg vertical limit.
Bulk Material Divertor
Shifts heavy bulk material flow on wide conveyor lines using the CB clevis mount to absorb pivot stress.
Replacing the Airtac SI125 Standard Cylinder SI125X400CB with the SAI125X400CB
To replace the discontinued SI125X400CB, order the SAI125X400CB and verify your ISO 15552 CB clevis mount, 400 mm stroke, and G1/2 port. If you need to size both ways, the neighboring 100 mm bore yields 3927 N push at 0.5 MPa, while the 160 mm bore yields 10053 N. This plain cylinder does not hold load without live air; the cushion only decelerates. For load holding on air loss, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variants. Since the 400 mm stroke increases side-load and rod-bending risks, ensure external guiding. Finally, this no-magnet SKU cannot take a CS1-B/DS1-B sensor.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X400CB
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI125 Standard Cylinder SI125X400CB FAQ
Yes, the AirTAC SI125X400CB is discontinued. The direct replacement is the SAI125X400CB. It is dimensionally interchangeable per the ISO 15552 mounting interface, retaining the same 125 mm bore, 400 mm stroke, force, G1/2 port, and CB clevis mounting.
This double-acting cylinder features a G1/2 port and delivers a push force of 6136 N and pull of 5734 N at 0.5 MPa. At 0.7 MPa push is 8590 N, and 11045 N at 0.9 MPa. The theoretical max force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X400CB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X400CB replacement — usually within 7-8 hours.