This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X100STC, 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 SI125X100STC
The AirTAC SI125 Standard Cylinder SI125X100STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 100mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X100STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke100 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X100STC
- 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 SI125X100STC
The AirTAC SI125X100STC is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 100 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125X100STC, a direct upgrade retaining the exact TC trunnion mount, M27x2 thread, and dimensions.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. For demanding thermal environments, a Viton H seal option extends operation to 150 C. The built-in magnet supports legacy CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125X100STC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X100STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X100STC |
| Bore size | Ø125 mm |
| Stroke | 100 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 SAI125X100STC 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 SAI125X100STC 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 SI125X100STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×100 | 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 SI125X100STC Is Used
Heavy Press Operations
Drives large platens for industrial metal forming and pressing tasks needing up to 11045 N thrust at 0.7 MPa.
Pallet Handling
Shifts heavy loaded pallets on conveyor lines using the TC trunnion mount to absorb lateral moments.
Large Mold Clamping
Secures substantial injection molds with a 313 kg vertical lift capacity and stable 125 mm profile body.
Replacing the Airtac SI125 Standard Cylinder SI125X100STC with the SAI125X100STC
To replace the SI125X100STC, order the SAI125X100STC. Verify the ISO 15552 TC trunnion mounting interface, 125 mm bore, 100 mm stroke, G1/2 port, and the -S magnet for position sensing. Sizing both ways: a 100 mm bore yields 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. If your application requires load holding on air loss, note that a plain cylinder drifts and its cushion only decelerates; use an external pilot check valve or the SAIL/BSAI lock variants. The 32 mm rod handles the 5734 N pull force securely.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X100STC
- ✓ 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 SI125X100STC FAQ
Yes, the SI125X100STC is discontinued. The direct replacement is the SAI125X100STC. It shares the identical ISO 15552 mounting interface, 125 mm bore, 100 mm stroke, G1/2 port, and TC mount, fitting existing fixtures perfectly.
It features a G1/2 air port. Force output is 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N push at 0.9 MPa, and a maximum theoretical force of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X100STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X100STC replacement — usually within 7-8 hours.