This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X75STC, 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 SI125X75STC
The AirTAC SI125 Standard Cylinder SI125X75STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 75mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X75STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke75 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X75STC
- 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 SI125X75STC
The AirTAC SI125X75STC is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 75 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X75STC, matching the TC trunnion mount, M27x2 thread, and output force.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure. The SAI family also adds SAIL lock and BSAI clamp variants absent in the SI line.
Airtac SI125 Standard Cylinder SI125X75STC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X75STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X75STC |
| Bore size | Ø125 mm |
| Stroke | 75 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 SAI125X75STC 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 SAI125X75STC 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 SI125X75STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×75 | 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 SI125X75STC Is Used
Heavy Press Clamping
Applies 6136 N of thrust at 0.5 MPa to secure large metal castings or heavy assemblies during machining and press operations.
Large Gate Actuation
Moves substantial industrial gates or diverters with a 75 mm stroke, relying on adjustable 40 mm air cushions to decelerate the 32 mm rod.
Replacing the Airtac SI125 Standard Cylinder SI125X75STC with the SAI125X75STC
To replace the SI125X75STC, order the SAI125X75STC. Verify the ISO 15552 TC trunnion mounting interface, 125 mm bore, 75 mm stroke, G1/2 port, and the -S magnet for CS1-B/DS1-B sensors (SAI uses current AirTAC switches). For sizing, the 100 mm bore yields 3927 N push at 0.5 MPa, while the 160 mm bore provides 10053 N. Note that a plain cylinder drifts on air loss; for load holding, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X75STC
- ✓ 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 SI125X75STC FAQ
Yes, the AirTAC SI125X75STC is discontinued. The direct replacement is the SAI125X75STC. It is dimensionally interchangeable per the ISO 15552 mounting interface, maintaining the same 125 mm bore, 75 mm stroke, G1/2 port, and TC trunnion mount.
The G1/2 port feeds a 32 mm rod. At 0.5 MPa it provides 6136 N push and 5734 N pull. 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. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X75STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X75STC replacement — usually within 7-8 hours.