This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX750S, 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 SI125AX750S
The AirTAC SI125 Standard Cylinder SI125AX750S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 750mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX750S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke750 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX750S
- 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 SI125AX750S
The AirTAC SI125AX750S is a discontinued double-acting ISO 15552 profile cylinder featuring a 125mm bore, 750mm stroke, and a SUS420J2 stainless piston rod. Delivering 6136N push force at 0.5MPa via a G1/2 port, it is replaced by the SAI125AX750S. This direct successor matches the exact mounting interface, bore, stroke, output force, and port size.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The original SI -S magnet supports CS1-B/DS1-B switches, while the SAI family adds SAIL lock, SAIF valve, and BSAI clamp-lock variants absent in the legacy line.
Airtac SI125 Standard Cylinder SI125AX750S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX750S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX750S |
| Bore size | Ø125 mm |
| Stroke | 750 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 SAI125AX750S 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 SAI125AX750S 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 SI125AX750S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×750 | 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 SI125AX750S Is Used
Heavy Stamping Press
Drives large heavy-duty stamping dies requiring 8590N push force at 0.7MPa with robust 32mm stainless rod endurance.
Bulk Material Divert
Shifts heavy bulk material diverters on wide conveyors, relying on adjustable 40mm cushions to decelerate loads.
Replacing the Airtac SI125 Standard Cylinder SI125AX750S with the SAI125AX750S
To replace the SI125AX750S, order the SAI125AX750S. Verify the ISO 15552 mounting interface, the G1/2 air port, the M27x2 rod thread, and the -S magnet for current AirTAC switches. The 750mm stroke is within the 1500mm standard maximum but requires external guides to prevent rod bending and manage side loads. Sizing both ways: a 100mm bore yields 3927N push at 0.5MPa, while a 160mm bore yields 10053N. Note that a plain cylinder drifts on air loss as cushions only decelerate; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. The Viton H seal option raises operating temperature to 150C.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX750S
- ✓ 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 SI125AX750S FAQ
Yes, the SI125AX750S is discontinued. The direct replacement is the SAI125AX750S. It is dimensionally interchangeable per the ISO 15552 mounting interface, maintaining the same 125mm bore, 750mm stroke, force, G1/2 port, and mounting accessories.
The G1/2 port bore 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. Speed is 30-500mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX750S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX750S replacement — usually within 7-8 hours.