This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX30, 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 SI40BX30
The AirTAC Airtac SI40 Standard Cylinder SI40BX30 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 30mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX30, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke30 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX30
- 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 SI40BX30
The AirTAC SI40BX30 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 30mm stroke. It delivers 628N push and 528N pull at 0.5MPa, utilizing a G1/4 port. Because this legacy unit is end-of-life, you should order the direct replacement: the SAI40BX30. The SAI maintains the same ISO 15552 mounting interface, bore, stroke, output force, port size, and accessories, fitting existing fixtures perfectly.
The SAI upgrade introduces an upgraded piston seal featuring two Y-shaped one-way elements for low start-up pressure and extended life. This SKU uses a SUS304 stainless steel rod (-B) for corrosion resistance, but lacks a magnet (-S), meaning it cannot accept a magnetic switch.
Airtac SI40 Standard Cylinder SI40BX30 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX30 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX30 |
| Bore size | Ø40 mm |
| Stroke | 30 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 SAI40BX30 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 SAI40BX30 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 SI40BX30
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×30 | 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 SI40BX30 Is Used
Compact Ejection
Ideal for short-stroke part ejection in machining centers, where the 628N push force reliably clears machined components from fixtures.
Transfer Diverting
Drives small diverters on packaging lines, using the 30mm stroke to push lightweight cartons between adjacent conveyor belts.
Stainless Rod Gaging
The SUS304 rod excels in washdown gaging stations, offering corrosion resistance while positioning stops in material handling.
Replacing the Airtac SI40 Standard Cylinder SI40BX30 with the SAI40BX30
To replace the SI40BX30, order the SAI40BX30, confirming the ISO 15552 mounting interface, 40mm bore, 30mm stroke, G1/4 port (PT/G/NPT), and mounting accessory. This SKU lacks a magnet, so it cannot support sensing; if position detection is needed, select an SAI40X30S and use current AirTAC switches. When sizing, note the 40mm bore yields 628N push at 0.5MPa; dropping to a 32mm bore gives 402N, while a 50mm bore provides 982N. A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding, use an external pilot check valve or explore the SAIL or BSAI lock variants. The SAIF variant adds a built-in valve for bores 32-100.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX30
- ✓ 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 SI40BX30 FAQ
Yes, the SI40BX30 is discontinued. The direct replacement is the SAI40BX30. It is dimensionally interchangeable per ISO 15552, keeping the same 40mm bore, 30mm stroke, 628N force, G1/4 port, and mounting interface.
The 40mm bore features a G1/4 port, a 16mm rod, and M12x1.25 thread. It generates 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, and a theoretical maximum of 128kgf at 1.0MPa.
Request a Quote for the SAI40BX30
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX30 replacement — usually within 7-8 hours.