This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX290, 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 SI40BX290
The AirTAC Airtac SI40 Standard Cylinder SI40BX290 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 290mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX290, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke290 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX290
- 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 SI40BX290
The AirTAC SI40BX290 is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 290mm stroke, and a SUS304 stainless steel rod. It delivers 628 N of push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40BX290, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, and force.
The SAI successor introduces an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. Note this SKU lacks a magnet (-S) and cannot accept a CS1-B/DS1-B sensor.
Airtac SI40 Standard Cylinder SI40BX290 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX290 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX290 |
| Bore size | Ø40 mm |
| Stroke | 290 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 SAI40BX290 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 SAI40BX290 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 SI40BX290
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×290 | 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 SI40BX290 Is Used
Washdown Sorting
Ideal for food or pharmaceutical lines where the SUS304 rod resists moisture, pushing light packages with 628 N at 0.5 MPa.
Replacing the Airtac SI40 Standard Cylinder SI40BX290 with the SAI40BX290
To replace the SI40BX290, order the SAI40BX290. Confirm the ISO 15552 mounting interface, the 40mm bore, the 290mm stroke, and the G1/4 port. Because this variant uses a -B SUS304 stainless rod, verify you select the same corrosion-resistant material option on the SAI. This non-magnetic SKU cannot support position sensing; if you need switches, order an SAI40BX290S and use current AirTAC sensors. At 290mm stroke, use guide rails to prevent rod bending and side-load damage. For sizing, the neighbouring 32mm bore offers 563 N push at 0.7 MPa, while the 50mm bore provides 1374 N. A plain cylinder drifts on air loss; for load holding, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX290
- ✓ 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 SI40BX290 FAQ
Yes, the SI40BX290 is discontinued. The direct replacement is the AirTAC SAI40BX290. It shares the identical ISO 15552 mounting interface, 40mm bore, 290mm stroke, G1/4 port, and output force, fitting directly into existing fixtures.
This double-acting cylinder uses a G1/4 air port. 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 of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX290
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX290 replacement — usually within 7-8 hours.