This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX750S, 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 SI40BX750S
The AirTAC Airtac SI40 Standard Cylinder SI40BX750S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 750mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX750S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke750 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX750S
- 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 SI40BX750S
The AirTAC SI40BX750S is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore, 750 mm stroke, and a SUS304 stainless steel rod. It delivers 628 N push and 528 N pull at 0.5 MPa through a G1/4 port. The direct replacement is the SAI40BX750S, which shares the exact ISO 15552 mounting interface, bore, stroke, output force, and porting.
The SAI upgrade introduces a two Y-shaped one-way piston seal for lower start-up pressure and longer life. This -S model includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI accepts current AirTAC switches. A Viton H seal option raises the operating temperature to 0-150 C.
Airtac SI40 Standard Cylinder SI40BX750S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX750S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX750S |
| Bore size | Ø40 mm |
| Stroke | 750 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 SAI40BX750S 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 SAI40BX750S 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 SI40BX750S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | 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 SI40 Standard Cylinder SI40BX750S Is Used
Long-Stroke Diversion
Drives 750 mm sorting gates on packaging lines, utilizing the SUS304 stainless rod for corrosion resistance in washdown environments.
Stainless Transfer Assembly
Shifts workpiece carriers between machining stations, using the G1/4 port and ISO 15552 mounts for seamless fixture integration.
Replacing the Airtac SI40 Standard Cylinder SI40BX750S with the SAI40BX750S
To replace the SI40BX750S, order the SAI40BX750S. Confirm the ISO 15552 mounting interface (LB, FA, FB, CA, CB, TC), the G1/4 port, the M12x1.25 rod thread, and the -S magnet for switch sensing. If you need more force, the neighbouring 50 mm bore provides 982 N push at 0.5 MPa; if less force is acceptable, the 32 mm bore offers 402 N. Because the stroke is 750 mm, add an external guide to prevent rod bending and side-load damage. A plain cylinder does not hold load without live air—the cushion only decelerates—so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants for secure holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX750S
- ✓ 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 SI40BX750S FAQ
Yes, the SI40BX750S is discontinued. The direct replacement is the SAI40BX750S. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 750 mm stroke, G1/4 port, and mounting interface to fit existing fixtures directly.
This double-acting cylinder features a G1/4 air port and an M12x1.25 rod thread. It generates 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 theoretical maximum force of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX750S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX750S replacement — usually within 7-8 hours.