This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX115S, 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 SI125AX115S
The AirTAC SI125 Standard Cylinder SI125AX115S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 115mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX115S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke115 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX115S
- 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 SI125AX115S
The AirTAC SI125AX115S is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 115mm stroke, delivering 6136N push force at 0.5MPa. It features an SUS420J2 stainless piston rod and a built-in magnet for legacy CS1-B/DS1-B sensors. AirTAC replaced this end-of-life unit with the SAI125AX115S, a direct replacement retaining the exact G1/2 port, M27x2 thread, and ISO 15552 mounting interface.
The SAI upgrade introduces a two Y-shaped one-way piston seal for lower start-up pressure and longer life. The SAI family also adds SAIL and BSAI lock variants absent from the SI line, while a Viton H seal option raises operating temperature to 150C.
Airtac SI125 Standard Cylinder SI125AX115S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX115S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX115S |
| Bore size | Ø125 mm |
| Stroke | 115 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 SAI125AX115S 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 SAI125AX115S 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 SI125AX115S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×115 | 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 SI125AX115S Is Used
Heavy Stamping
Drives large press dies and forming tools requiring 6136N of thrust at 0.5MPa with stable 125mm bore guidance.
Pallet Handling
Indexes heavy loaded pallets along conveyors, using the 115mm stroke to push loads firmly into staging zones.
Clamp Fixturing
Secures large fabricated steel frames during welding or machining using the robust 32mm SUS420J2 stainless rod.
Replacing the Airtac SI125 Standard Cylinder SI125AX115S with the SAI125AX115S
To replace the SI125AX115S, order the SAI125AX115S and verify your ISO 15552 mounting fixtures, G1/2 port, and M27x2 rod thread. The -S magnet and -A SUS420J2 rod carry over directly. Sizing both ways: this bore yields 6136N push at 0.5MPa; stepping down to an 80mm bore gives 2513N, while a 160mm bore provides 10053N. For this 115mm stroke, side-load is minimal, but if you upgrade to strokes over 300mm, add external guide rails to prevent rod bending. Note that a plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock or pilot check valve for load holding, or specify an SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX115S
- ✓ 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 SI125AX115S FAQ
Yes, the SI125AX115S is discontinued. The direct replacement is the SAI125AX115S. It is dimensionally interchangeable per the ISO 15552 mounting interface, maintaining the same 125mm bore, 115mm stroke, output force, G1/2 port, and mounting accessories.
This 125mm bore cylinder uses a G1/2 air 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX115S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX115S replacement — usually within 7-8 hours.