This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX500, 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 SI40BX500
The AirTAC Airtac SI40 Standard Cylinder SI40BX500 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 500mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX500, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke500 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX500
- 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 SI40BX500
The AirTAC SI40BX500 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 500mm stroke. Delivering 628N push force at 0.5MPa via a G1/4 port, it is replaced by the SAI40BX500. This direct successor shares identical mounting, stroke, and force specs. The B suffix denotes a SUS304 stainless steel rod for corrosion resistance, and because this SKU lacks a magnet, it cannot accept a position sensor.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. Note that a plain cylinder drifts on air loss; for load holding, explore the SAIL lock, BSAI clamp-lock, or an external pilot check valve.
Airtac SI40 Standard Cylinder SI40BX500 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX500 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX500 |
| Bore size | Ø40 mm |
| Stroke | 500 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 SAI40BX500 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 SAI40BX500 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 SI40BX500
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×500 | 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 SI40BX500 Is Used
Long-Stroke Diversion
Pushes packages across transfer lines with a 500mm reach, relying on the SUS304 rod for humid washdown environments.
Vertical Material Lift
Raises lightweight bins up to 32kg, requiring external guidance to prevent side-loading on the extended 16mm rod.
Pneumatic Gate Actuation
Opens and closes access doors on machinery, taking advantage of the adjustable 27mm cushions to soften end-of-stroke impacts.
Replacing the Airtac SI40 Standard Cylinder SI40BX500 with the SAI40BX500
To replace the SI40BX500, order the SAI40BX500. Verify your ISO 15552 interface, G1/4 port, and mounting accessory (LB, FA, TC, etc.). This non-magnetic SKU cannot support switches; if sensing is needed, select an SAI40X500S model and use current AirTAC switches. For 500mm strokes, prevent rod bending by guiding the load externally. If you need more force, the 50mm bore offers 982N at 0.5MPa; if less is acceptable, the 32mm bore provides 402N. Remember that cushions only decelerate; for static holding, use the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX500
- ✓ 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 SI40BX500 FAQ
Yes, the SI40BX500 is discontinued. The direct replacement is the SAI40BX500. It is dimensionally interchangeable per ISO 15552, maintaining the same 40mm bore, 500mm stroke, 628N force, G1/4 port, and mounting interface.
This 40mm bore cylinder uses a G1/4 air port. It generates 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical maximum of 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX500
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX500 replacement — usually within 7-8 hours.