This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X37, 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 SI125X37
The AirTAC SI125 Standard Cylinder SI125X37 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 37mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X37, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke37 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X37
- 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 SI125X37
The AirTAC SI125X37 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 37 mm stroke, delivering 6136 N push force at 0.5 MPa. AirTAC replaced this legacy unit with the SAI125X37. This direct upgrade shares the exact ISO 15552 mounting interface, G1/2 port, and M27x2 rod thread, fitting existing fixtures seamlessly.
The SAI125X37 features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Because this specific SI125X37 SKU lacks a magnet (-S), it cannot accept position sensors. For locking needs the SI line lacked, explore SAIL or BSAI variants.
Airtac SI125 Standard Cylinder SI125X37 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X37 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X37 |
| Bore size | Ø125 mm |
| Stroke | 37 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 SAI125X37 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 SAI125X37 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 SI125X37
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×37 | 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 SI125X37 Is Used
Heavy Stamp Pressing
Ideal for short-stroke high-force stamping tasks, utilizing the 6136 N push force at 0.5 MPa to form thick metal components securely.
Industrial Clamping
Provides rigid 125 mm bore clamping action for large weldments, holding heavy structural parts firmly in place during automated assembly.
Pallet Positioning
Acts as a robust stopper or alignment pusher for heavy loaded pallets, using its 313 kg vertical lift capacity to shift goods on conveyors.
Replacing the Airtac SI125 Standard Cylinder SI125X37 with the SAI125X37
To replace the SI125X37, order the SAI125X37. Confirm the ISO 15552 mounting interface, 125 mm bore, 37 mm stroke, G1/2 port (PT/G/NPT), and mounting accessory. Since this SKU has no -S magnet, it cannot take CS1-B/DS1-B sensors; order a magnet-equipped SAI if sensing is needed. The 125 mm bore yields 6136 N push at 0.5 MPa; if less force is required, step down to a 100 mm bore (3927 N). For load holding on air loss, note a plain cylinder drifts—the cushion only decelerates. Use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. The 37 mm stroke is short, so side-load risks are minimal, but always verify rod alignment.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X37
- ✓ 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 SI125X37 FAQ
Yes, the AirTAC SI125X37 is discontinued. The direct replacement is the SAI125X37. It shares the same ISO 15552 mounting interface, 125 mm bore, 37 mm stroke, output force, G1/2 port, and accessories, fitting existing fixtures perfectly.
The 125 mm bore features a G1/2 port and M27x2 rod thread. 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, with a theoretical max of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X37
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X37 replacement — usually within 7-8 hours.