This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX475S, 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 SI40 Standard Cylinder SI40BX475S
The AirTAC Airtac SI40 Standard Cylinder SI40BX475S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 475mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX475S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke475 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX475S
- 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 SI40 Standard Cylinder SI40BX475S
The AirTAC SI40BX475S is a discontinued double-acting ISO 15552 profile cylinder featuring a 40 mm bore, 475 mm stroke, and a SUS304 stainless steel piston rod. It delivers 628 N push force at 0.5 MPa through a G1/4 port. The direct replacement is the SAI40BX475S, matching the exact bore, stroke, force, and ISO 15552 mounting interface.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The original -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL and BSAI lock variants the SI lacked.
Airtac SI40 Standard Cylinder SI40BX475S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX475S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX475S |
| Bore size | Ø40 mm |
| Stroke | 475 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| 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 – 800 mm/s |
| Cushion | Adjustable, 27 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI40BX475S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
The SAI40BX475S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI40 Standard Cylinder SI40BX475S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | 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 SI40 Standard Cylinder SI40BX475S Is Used
Diverting Gate Actuation
Drives routing flaps on packaging lines where the 475 mm stroke provides full lane separation, utilizing the 628 N push force at 0.5 MPa to overcome friction.
Carton Push-off
Ejects packaged goods from conveyors, relying on the adjustable 27 mm air cushions to decelerate the payload smoothly at stroke ends.
Replacing the Airtac SI40 Standard Cylinder SI40BX475S with the SAI40BX475S
To replace the SI40BX475S, order the SAI40BX475S and confirm the ISO 15552 interface, 40 mm bore, 475 mm stroke, G1/4 port, and mounting accessories. The -B rod is SUS304 stainless steel, and the -S magnet works with CS1-B/DS1-B switches. For sizing, a 32 mm bore yields 402 N push at 0.5 MPa, while a 50 mm bore yields 982 N. Because this is a 475 mm stroke, use external guides to prevent rod bending and side-load wear. A plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX475S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI40 Standard Cylinder SI40BX475S FAQ
Yes, the SI40BX475S is discontinued. The direct replacement is the SAI40BX475S. It is dimensionally interchangeable per ISO 15552, maintaining the same 40 mm bore, 475 mm stroke, 628 N force, G1/4 port, and mounting interface.
This 40 mm bore cylinder features a G1/4 air port and M12x1.25 rod thread. Theoretical forces are: 628 N push and 528 N pull at 0.5 MPa, 879 N push at 0.7 MPa, 1130 N push at 0.9 MPa, and a maximum of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX475S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX475S replacement — usually within 7-8 hours.