This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX15S, 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 SI40BX15S
The AirTAC SI40 Standard Cylinder SI40BX15S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 15mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX15S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke15 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX15S
- 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 SI40BX15S
The AirTAC SI40BX15S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore, 15mm stroke, and a SUS304 stainless piston rod. Delivering 628 N push force at 0.5 MPa, it is directly replaced by the SAI40BX15S. This direct SAI upgrade matches the original G1/4 port, M12x1.25 thread, and ISO 15552 mounting interface exactly.
The SAI successor introduces an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked. Your existing CS1-B/DS1-B sensors fit the -S magnet here, though the SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40BX15S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX15S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX15S |
| Bore size | Ø40 mm |
| Stroke | 15 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 SAI40BX15S 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 SAI40BX15S 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 SI40BX15S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×15 | 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 SI40BX15S Is Used
Short-Stroke Clamping
Ideal for compact 15mm clamping tasks in machining fixtures, utilizing the 628 N push force at 0.5 MPa to secure parts firmly.
Corrosive Environment Actuation
The SUS304 stainless rod option makes this 40mm bore cylinder suitable for packaging lines or washdown areas where carbon steel would corrode.
Ejector Mechanisms
Provides reliable, short-travel ejection of small components on assembly lines, operating efficiently at speeds of 30-800 mm/s.
Replacing the Airtac SI40 Standard Cylinder SI40BX15S with the SAI40BX15S
To replace this SI40BX15S, order the SAI40BX15S, confirming the ISO 15552 interface, 40mm bore, 15mm stroke, G1/4 port, and SUS304 rod. If sizing up or down, adjacent bores are 32mm and 50mm. At 0.5 MPa, the 32mm bore yields 402 N push, while the 50mm bore provides 982 N. Note that a plain cylinder drifts on air loss; the 27mm air cushion only decelerates near stroke end. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. The SAIF variant adds a built-in valve for bores 32-100.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX15S
- ✓ 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 SI40BX15S FAQ
Yes, the SI40BX15S is discontinued. The direct replacement is the SAI40BX15S. It features the same ISO 15552 mounting interface, 40mm bore, 15mm stroke, G1/4 port, and SUS304 stainless rod, fitting existing fixtures perfectly.
The G1/4 port is fixed by the 40mm bore. At 0.5 MPa it provides 628 N push and 528 N pull force. At 0.7 MPa push is 879 N, and at 0.9 MPa it is 1130 N. The theoretical maximum force is 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX15S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX15S replacement — usually within 7-8 hours.