This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX125, 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 SI125AX125
The AirTAC SI125 Standard Cylinder SI125AX125 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 125mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX125, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke125 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX125
- 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 SI125AX125
The AirTAC SI125AX125 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 125 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125AX125, a direct replacement retaining the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. This specific SKU lacks a magnet (-S), so it cannot accept position sensors like the legacy CS1-B/DS1-B switches. For high-temperature environments, Viton H seals raise the operating limit to 150 C.
Airtac SI125 Standard Cylinder SI125AX125 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX125 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX125 |
| Bore size | Ø125 mm |
| Stroke | 125 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 SAI125AX125 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 SAI125AX125 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 SI125AX125
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×125 | 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 SI125AX125 Is Used
Heavy Stamping Press
Drives large forming dies with 6136 N thrust at 0.5 MPa, utilizing the robust 32 mm piston rod for high-impact metal fabrication.
Pallet Handling Gate
Actuates heavy-duty conveyor diverts and lift gates, where the direct replacement SAI125AX125 maintains the exact ISO 15552 mounting footprint.
Plastic Injection Unloading
Ejects molded parts from machinery, leveraging the SUS420J2 stainless rod option to resist moisture and cooling fluid corrosion.
Replacing the Airtac SI125 Standard Cylinder SI125AX125 with the SAI125AX125
To replace the discontinued SI125AX125, order the SAI125AX125. Verify your ISO 15552 mounting accessories (LB, FA, CA, TC) and confirm the G1/2 port thread (PT, G, or NPT). Because this SKU has no magnet, it cannot support switches; if sensing is needed, select an SAI125X125S model and use current AirTAC sensors. For sizing, the 125 mm bore yields 6136 N push at 0.5 MPa; if less force is acceptable, a 100 mm bore provides 3927 N. For load holding, note that a standard cylinder drifts on air loss—the cushion only decelerates. Use an external pilot check valve or explore the SAIL or BSAI lock variants. This unit features the SUS420J2 stainless steel rod (-A) for corrosion resistance. Since the stroke is under 300 mm, rod-bending side loads are minimal, but always guide the load.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX125
- ✓ 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 SI125AX125 FAQ
Yes, the AirTAC SI125AX125 is discontinued. The direct replacement is the SAI125AX125. It shares the identical ISO 15552 mounting interface, 125 mm bore, 125 mm stroke, G1/2 port, and force output, fitting directly into existing fixtures.
This double-acting cylinder uses a G1/2 air port. It generates 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 theoretical maximum of 1251 kgf at 1.0 MPa. The operating speed range is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX125
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX125 replacement — usually within 7-8 hours.