This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX150S, 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 SI40BX150S
The AirTAC Airtac SI40 Standard Cylinder SI40BX150S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 150mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX150S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke150 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX150S
- 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 SI40BX150S
The AirTAC SI40BX150S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore, 150mm stroke, and a SUS304 stainless steel rod. It delivers 628 N push force at 0.5 MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40BX150S, a direct replacement sharing the exact ISO 15552 mounting interface, stroke, and output force.
The SAI upgrade features a new piston seal using two Y-shaped one-way elements for low start-up pressure and long life. This -S variant includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI40 Standard Cylinder SI40BX150S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX150S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX150S |
| Bore size | Ø40 mm |
| Stroke | 150 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 SAI40BX150S 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 SAI40BX150S 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 SI40BX150S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×150 | 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 SI40BX150S Is Used
Stainless Rod Actuation
Ideal for packaging machinery requiring a 628 N push force where the SUS304 rod provides corrosion resistance against washdowns.
Material Diversion
Provides reliable 150mm stroke diverting action on conveyor lines, safely handling products up to the 377 N working load limit.
Vertical Lift Gates
Suitable for raising lightweight access gates or covers up to 32 kg, utilizing the double-acting 0.7 MPa thrust for positive lifting.
Replacing the Airtac SI40 Standard Cylinder SI40BX150S with the SAI40BX150S
To replace the SI40BX150S, order the SAI40BX150S and confirm the ISO 15552 mounting interface, 40mm bore, 150mm stroke, G1/4 port, and your specific mounting accessory. The -B rod is SUS304 stainless steel, and the -S magnet works with legacy CS1-B/DS1-B switches (the SAI uses current AirTAC switches). For sizing alternatives, a 32mm bore yields 402 N push at 0.5 MPa, while a 50mm bore yields 982 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. Since the stroke is 150mm, ensure guide alignment to prevent rod bending side-loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX150S
- ✓ 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 SI40BX150S FAQ
Yes, the AirTAC SI40BX150S is discontinued. The direct replacement is the SAI40BX150S. It is a true ISO 15552 profile cylinder with the same 40mm bore, 150mm stroke, 628 N force, G1/4 port, and mounting interface, so it drops directly into existing fixtures.
The bore is 40mm with a G1/4 air port. The thrust ratings 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 theoretical maximum force of 128 kgf at 1.0 MPa. The rod is 16mm with an M12x1.25 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX150S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX150S replacement — usually within 7-8 hours.