This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX20, 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 SI125AX20
The AirTAC SI125 Standard Cylinder SI125AX20 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 20mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX20, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke20 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX20
- 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 SI125AX20
The AirTAC SI125AX20 is a discontinued double-acting ISO 15552 profile cylinder featuring a 125mm bore and 20mm stroke. It delivers 6136N push force at 0.5MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125AX20, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, force, and port size.
The SAI125AX20 features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. This specific SKU uses a SUS420J2 stainless steel rod (the -A option) for corrosion resistance. Lacking the -S magnet suffix, it cannot accept a position sensor. For load-holding, note that standard air cushions only decelerate; use an external pilot check valve or the SAIL/BSAI lock variants.
Airtac SI125 Standard Cylinder SI125AX20 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX20 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX20 |
| Bore size | Ø125 mm |
| Stroke | 20 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 SAI125AX20 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 SAI125AX20 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 SI125AX20
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×20 | 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 SI125AX20 Is Used
Heavy Stamp Pressing
Uses the 6136N push force at 0.5MPa to firmly seat and stamp heavy-gauge metal components in automated fabrication lines.
Pallet Stopper Gate
Functions as a robust short-stroke 20mm barrier to halt heavy 313kg vertical loads or pallets at conveyor transfer points.
High-Force Clamping
Secures large workpieces during machining, leveraging the 125mm bore and SUS420J2 stainless rod for industrial durability.
Replacing the Airtac SI125 Standard Cylinder SI125AX20 with the SAI125AX20
To replace the SI125AX20, order the SAI125AX20. Verify the ISO 15552 mounting fixtures, the G1/2 air port, and the M27x2 rod thread. Because this SKU lacks the -S magnet, it cannot support legacy CS1-B/DS1-B sensors; order a magnet-equipped SAI125AS variant if position feedback is needed. The 125mm bore yields 6136N push at 0.5MPa; if downsizing, a 100mm bore gives 3927N. For load holding on air loss, the cushion only decelerates—select the SAIL or BSAI lock variant, or add an external rod lock. The -A rod provides SUS420J2 stainless steel for damp environments.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX20
- ✓ 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 SI125AX20 FAQ
Yes, the AirTAC SI125AX20 is discontinued. The direct replacement is the SAI125AX20. It shares the identical ISO 15552 mounting interface, 125mm bore, 20mm stroke, output force, and G1/2 port, fitting directly into existing fixtures.
It features a G1/2 port and delivers 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N push at 0.9MPa, and a theoretical max of 1251kgf at 1.0MPa. Operating speed is 30-500mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX20
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX20 replacement — usually within 7-8 hours.