This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX165S, 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 SI125AX165S
The AirTAC SI125 Standard Cylinder SI125AX165S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 165mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX165S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke165 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX165S
- 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 SI125AX165S
The AirTAC SI125AX165S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 165 mm stroke. Delivering 6136 N push force at 0.5 MPa, it features an SUS420J2 stainless steel rod, a G1/2 port, and a built-in magnet for CS1-B/DS1-B sensors. AirTAC replaced this legacy unit with the SAI125AX165S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, and output force.
The SAI replacement features an upgraded piston seal using two Y-shaped one-way elements for low start-up pressure and extended life. For applications needing load holding on air loss, the SAI family introduces BSAI clamp-lock and SAIL air-released lock variants unavailable in the SI line.
Airtac SI125 Standard Cylinder SI125AX165S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX165S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX165S |
| Bore size | Ø125 mm |
| Stroke | 165 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 SAI125AX165S 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 SAI125AX165S 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 SI125AX165S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×165 | 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 SI125AX165S Is Used
Heavy Pressing Operations
Applies the 8590 N push force at 0.7 MPa for securely seating large bearings or forming thick metal components in automated machinery.
Material Clamp Systems
Holds heavy workpieces stationary during machining, utilizing the robust 32 mm SUS420J2 stainless piston rod to resist side loading.
Replacing the Airtac SI125 Standard Cylinder SI125AX165S with the SAI125AX165S
To replace the discontinued SI125AX165S, order the SAI125AX165S. Verify your ISO 15552 mounting accessories (LB, FA, TC, etc.), the G1/2 air port, and the M27x2 rod thread. The -S magnet accommodates legacy CS1-B/DS1-B switches, though the SAI replacement uses current AirTAC sensors. When sizing, neighbouring bores offer different forces: the 100 mm bore provides 3927 N push at 0.5 MPa, while the 160 mm bore yields 10053 N. A plain cylinder drifts on air loss, as the 40 mm adjustable air cushion only decelerates near stroke end; for secure holding, use an external pilot check valve or the SAIL/BSAI lock variant. The -A rod specifies SUS420J2 stainless steel for corrosion resistance.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX165S
- ✓ 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 SI125AX165S FAQ
Yes, the AirTAC SI125AX165S is discontinued. The direct replacement is the SAI125AX165S. It shares the same ISO 15552 mounting interface, 125 mm bore, 165 mm stroke, output force, and G1/2 port, fitting existing fixtures directly.
This 125 mm bore cylinder features a G1/2 air port and M27x2 rod thread. It delivers 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX165S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX165S replacement — usually within 7-8 hours.