This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X250CA, 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 SI125X250CA
The AirTAC SI125 Standard Cylinder SI125X250CA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 250mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X250CA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke250 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X250CA
- 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 SI125X250CA
The AirTAC SI125X250CA is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 250 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X250CA, retaining the same CA clevis mounting and interface dimensions.
This SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. The original SI line lacked SAIL lock, SAIF valve, and BSAI clamp-lock variants now available. Note this no-magnet SKU cannot accept sensors.
Airtac SI125 Standard Cylinder SI125X250CA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X250CA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X250CA |
| Bore size | Ø125 mm |
| Stroke | 250 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 SAI125X250CA 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 SAI125X250CA 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 SI125X250CA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×250 | 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 SI125X250CA Is Used
Heavy Stamping Press
Drives large dies and heavy platens using 6136 N of thrust at 0.5 MPa, relying on the 40 mm adjustable air cushions to absorb impact at stroke ends.
Large Gate Diverter
Actuates heavy material flow gates on conveyor lines, benefiting from the robust 32 mm piston rod and G1/2 air supply for rapid 30-500 mm/s cycling.
Replacing the Airtac SI125 Standard Cylinder SI125X250CA with the SAI125X250CA
To replace the SI125X250CA, order the SAI125X250CA confirming the ISO 15552 interface, 125 mm bore, 250 mm stroke, G1/2 port, and CA clevis mount. This SKU lacks the -S magnet, so it cannot accept CS1-B/DS1-B switches; order a magnet-equipped SAI if sensing is needed. For sizing, neighboring bores are 100 mm (3927 N push @0.5) and 160 mm (10053 N). A plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external pilot check valve or the SAIL/BSAI lock variant. The 32 mm rod handles the 250 mm stroke, but guide external loads to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X250CA
- ✓ 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 SI125X250CA FAQ
Yes, the SI125X250CA is discontinued. The direct replacement is the SAI125X250CA. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 250 mm stroke, G1/2 port, and CA clevis mounting interface.
The G1/2 port feeds a 32 mm rod yielding 6136 N push and 5734 N pull at 0.5 MPa. At 0.7 MPa push is 8590 N, and 11045 N at 0.9 MPa. The theoretical maximum force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X250CA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X250CA replacement — usually within 7-8 hours.