This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX35, 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 SI40BX35
The AirTAC Airtac SI40 Standard Cylinder SI40BX35 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 SAI40BX35, 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 → SAI40BX35
- 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 SI40BX35
The AirTAC SI40BX35 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore, 35mm stroke, and a SUS304 stainless steel piston rod. Generating 628N push force at 0.5MPa, it is replaced by the SAI40BX35. This direct upgrade matches the G1/4 port, M12x1.25 thread, and ISO 15552 mounting interface.
The SAI features an upgraded piston seal with two Y-shaped elements for low start-up pressure. Note this SKU lacks a magnet, so it cannot take CS1-B/DS1-B sensors. For high heat, Viton H seals raise the range to 150C.
Airtac SI40 Standard Cylinder SI40BX35 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX35 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX35 |
| 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 SAI40BX35 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 SAI40BX35 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 SI40BX35
| 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 SI40BX35 Is Used
Stainless Rod Actuation
Ideal for compact clamping tasks requiring the SUS304 rod option for corrosion resistance in washdown or mildly chemical environments.
Short-Stroke Diverting
Provides reliable 35mm diverting or gating force on packaging lines, utilizing the 628N thrust at 0.5MPa.
Replacing the Airtac SI40 Standard Cylinder SI40BX35 with the SAI40BX35
To replace the SI40BX35, order the SAI40BX35, confirming the ISO 15552 interface, 40mm bore, 35mm stroke, G1/4 port, and SUS304 rod. Because this SKU has no magnet (-S), it cannot accept position sensors. If sizing up or down, adjacent bores are 32mm (402N push) and 50mm (982N push) at 0.5MPa. For load holding, note that a plain cylinder drifts on air loss; the 27mm cushion only decelerates. Use an external pilot check valve or the SAIL/BSAI lock variants. The SAIF variant integrates a 4M valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX35
- ✓ 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 SI40BX35 FAQ
Yes, the SI40BX35 is discontinued. The direct replacement is the SAI40BX35. It shares the same ISO 15552 mounting interface, 40mm bore, 35mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly.
The bore is 40mm with a G1/4 air port. Force output is 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical max of 128kgf at 1.0MPa. The rod is 16mm with an M12x1.25 thread.
Request a Quote for the SAI40BX35
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX35 replacement — usually within 7-8 hours.