This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X475S, 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 SI125X475S
The AirTAC SI125 Standard Cylinder SI125X475S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 475mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X475S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke475 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X475S
- 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 SI125X475S
The AirTAC SI125X475S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 475 mm stroke. It delivers 6136 N push force at 0.5 MPa and features a G1/2 port. AirTAC replaced this legacy unit with the SAI125X475S, a direct alternative sharing the exact ISO 15552 mounting interface, bore, stroke, output force, and accessories.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The -S suffix means it has a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI family also adds SAIL and BSAI lock variants the SI lacked.
Airtac SI125 Standard Cylinder SI125X475S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X475S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X475S |
| Bore size | Ø125 mm |
| Stroke | 475 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 SAI125X475S 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 SAI125X475S 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 SI125X475S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×475 | 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 SI125X475S Is Used
Heavy Pressing
Applies 6136 N at 0.5 MPa for seating heavy components and actuating large industrial presses.
Pallet Diverting
Uses the 475 mm stroke to push heavy pallets across material handling lines at high force.
Replacing the Airtac SI125 Standard Cylinder SI125X475S with the SAI125X475S
To replace the SI125X475S, order the SAI125X475S. Verify the ISO 15552 mounting interface, the G1/2 port, the M27x2 rod thread, and your mounting accessory (LB, FA, TC, etc.). The -S magnet equates to legacy CS1-B/DS1-B sensors; the SAI uses current AirTAC switches. If sizing up or down, neighbouring bores are 100 mm and 160 mm. At 0.5 MPa, the 100 mm bore yields 3927 N push, while the 160 mm bore yields 10053 N. Remember a plain cylinder drifts without live air; for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. Because the 475 mm stroke is long, prevent rod bending by using an external guide to absorb side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X475S
- ✓ 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 SI125X475S FAQ
Yes, the SI125X475S is discontinued. The direct replacement is the SAI125X475S. It shares the same ISO 15552 mounting interface, 125 mm bore, 475 mm stroke, output force, G1/2 port, and mounting accessories, fitting directly into existing fixtures.
The SI125X475S operates at 30-500 mm/s. Force ratings 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 max of 1251 kgf at 1.0 MPa. It uses a G1/2 port.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X475S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X475S replacement — usually within 7-8 hours.