This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX170S, 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 SI125AX170S
The AirTAC SI125 Standard Cylinder SI125AX170S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 170mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX170S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke170 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX170S
- 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 SI125AX170S
The AirTAC SI125AX170S is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 170mm stroke. It delivers 6136N push force at 0.5MPa via a G1/2 port. AirTAC replaced it with the SAI125AX170S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. This SI125AX170S includes the -A SUS420J2 stainless piston rod and -S magnet for CS1-B/DS1-B switches. Note the 40mm cushions only decelerate; for load holding, use the SAIL or BSAI lock variants.
Airtac SI125 Standard Cylinder SI125AX170S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX170S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX170S |
| Bore size | Ø125 mm |
| Stroke | 170 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 SAI125AX170S 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 SAI125AX170S 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 SI125AX170S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×170 | 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 SI125AX170S Is Used
Heavy Stamping
Drives large press dies with 6136N push force at 0.5MPa, utilizing the 170mm stroke for deep drawing operations.
Clamp Fixtures
Secures large welded assemblies during machining, taking advantage of the stable ISO 15552 profile barrel.
Replacing the Airtac SI125 Standard Cylinder SI125AX170S with the SAI125AX170S
To replace the SI125AX170S, order the SAI125AX170S. Confirm the ISO 15552 mounting interface, 125mm bore, 170mm stroke, G1/2 port (PT/G/NPT), and mounting accessory. The -S magnet enables current AirTAC switches, and the -A rod is SUS420J2 stainless. For sizing, a 100mm bore yields 3927N push at 0.5MPa, while a 160mm bore yields 10053N. The 125mm bore provides 8590N at 0.7MPa. The air cushion decelerates but does not hold load; for drop prevention, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. Since the 170mm stroke is under 300mm, side-load risks are low, but ensure alignment to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX170S
- ✓ 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 SI125AX170S FAQ
Yes, the SI125AX170S is discontinued. The direct replacement is the SAI125AX170S. It shares the same ISO 15552 mounting interface, 125mm bore, 170mm stroke, output force, and G1/2 port, fitting existing fixtures perfectly.
This double-acting cylinder has a G1/2 port. It delivers 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N push at 0.9MPa, and 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 SAI125AX170S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX170S replacement — usually within 7-8 hours.