This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX35S, 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 SI40BX35S
The AirTAC Airtac SI40 Standard Cylinder SI40BX35S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 35mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX35S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke35 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX35S
- 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 SI40BX35S
The AirTAC SI40BX35S is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 35mm stroke, and a SUS304 stainless steel rod. Delivering 628 N push force at 0.5 MPa, it is directly replaced by the SAI40BX35S. This direct upgrade shares the exact ISO 15552 mounting interface, G1/4 port, and M12x1.25 rod thread, fitting existing fixtures seamlessly.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The -S magnet works with legacy CS1-B/DS1-B sensors, while a plain cylinder will not hold a load without live air.
Airtac SI40 Standard Cylinder SI40BX35S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX35S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX35S |
| Bore size | Ø40 mm |
| Stroke | 35 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 SAI40BX35S 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 SAI40BX35S 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 SI40BX35S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×35 | 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 SI40BX35S Is Used
Short-Stroke Diversion
The 35mm stroke provides rapid actuation for diverting small to mid-weight products along a processing line at up to 800 mm/s.
Pneumatic Gate Control
Delivers 628 N push force at 0.5 MPa to reliably open and close material handling gates in compact ISO 15552 fixtures.
Replacing the Airtac SI40 Standard Cylinder SI40BX35S with the SAI40BX35S
To replace the discontinued SI40BX35S, order the SAI40BX35S. Confirm the ISO 15552 mounting interface, 40mm bore, 35mm stroke, G1/4 port, and mounting accessory. The -B rod is SUS304 stainless steel and the -S magnet requires CS1-B/DS1-B switches. If you need more force, the 50mm bore offers 982 N push at 0.5 MPa; if less is acceptable, the 32mm bore provides 402 N. Note that a standard cylinder drifts without live air—use an external rod lock or pilot check valve for load holding, or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX35S
- ✓ 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 SI40BX35S FAQ
Yes, the SI40BX35S is discontinued. The direct replacement is the SAI40BX35S. It shares the same ISO 15552 mounting interface, 40mm bore, 35mm stroke, force, G1/4 port, and SUS304 rod, fitting directly into existing setups.
The G1/4 port bore delivers a push force of 628 N and pull of 528 N at 0.5 MPa, 879 N push at 0.7 MPa, 1130 N at 0.9 MPa, and a theoretical max of 128 kgf at 1.0 MPa. Operating pressure is 0.15-1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX35S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX35S replacement — usually within 7-8 hours.