This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX170, 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 SI125AX170
The AirTAC SI125 Standard Cylinder SI125AX170 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 SAI125AX170, 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 → SAI125AX170
- 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 SI125AX170
The AirTAC SI125AX170 is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 170mm stroke. This legacy unit delivers 6136 N push and 5734 N pull at 0.5 MPa, utilizing a G1/2 air port and an M27x2 rod thread. AirTAC replaced it with the SAI125AX170 direct replacement, featuring the exact same ISO 15552 mounting interface, output force, and port size to fit existing fixtures seamlessly.
The current-production SAI125AX170 upgrades the piston seal to two Y-shaped one-way elements for low start-up pressure and extended life. This specific SI125AX170 variant includes the -A code, meaning it uses a SUS420J2 stainless steel piston rod for corrosion resistance rather than standard carbon steel. Because it lacks the -S magnet suffix, this SKU cannot accept position sensors.
Airtac SI125 Standard Cylinder SI125AX170 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX170 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX170 |
| 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 SAI125AX170 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 SAI125AX170 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 SI125AX170
| 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 SI125AX170 Is Used
Heavy-Duty Pressing
Applies the 6136 N push force at 0.5 MPa for seating large bearings or clinching heavy metal components in automated fabrication lines.
Vertical Load Lowering
Lowers payloads up to 313 kg safely, relying on the 40mm adjustable air cushions to decelerate the mass smoothly at the end of the 170mm stroke.
Corrosive Environment Actuation
Leverages the SUS420J2 stainless piston rod to drive heavy clamps or doors in washdown areas or humid production facilities where carbon steel would degrade.
Replacing the Airtac SI125 Standard Cylinder SI125AX170 with the SAI125AX170
To replace the discontinued SI125AX170, order the SAI125AX170 while confirming the ISO 15552 mounting interface, the 170mm stroke, the G1/2 port, and the SUS420J2 stainless rod (-A). Because this SKU lacks a magnet (-S), it cannot support legacy CS1-B/DS1-B sensors; if position detection is needed, select an SAI equivalent with the magnet option and current AirTAC switches. Sizing both ways: the 125mm bore gives 6136 N push at 0.5 MPa, but if you need less force, a 100mm bore provides 3927 N at 0.5 MPa (or 5497 N at 0.7 MPa). Note that a plain cylinder does not hold load without live air; the 40mm adjustable cushions only decelerate near stroke end. For load-holding on air loss, use an external pilot check valve or explore the SAIL (air-released lock) or BSAI (clamp-lock) variants. With a 170mm stroke, side-load and rod-bending risks are moderate, but ensure adequate guide support.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX170
- ✓ 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 SI125AX170 FAQ
Yes, the AirTAC SI125AX170 is discontinued and end-of-life. The direct replacement is the SAI125AX170. It is dimensionally interchangeable per ISO 15552, maintaining the same 125mm bore, 170mm stroke, G1/2 port, and mounting interface. You simply order the SAI equivalent.
This 125mm bore cylinder uses a G1/2 air port. The thrust outputs are: 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 force of 1251 kgf at 1.0 MPa. It operates at speeds of 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX170
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX170 replacement — usually within 7-8 hours.