This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX350SH, 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 SI40BX350SH
The AirTAC Airtac SI40 Standard Cylinder SI40BX350SH is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 350mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX350SH, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke350 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX350SH
- 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 SI40BX350SH
The AirTAC SI40BX350SH is a discontinued double-acting ISO 15552 profile cylinder featuring a SUS304 stainless piston rod, Viton H high-temperature seals, and a 350 mm stroke. Delivering 628 N push force at 0.5 MPa, it is superseded by the SAI40BX350SH direct replacement. This upgrade shares the exact ISO 15552 mounting interface, G1/4 port, and output force, fitting existing fixtures seamlessly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The SAI family also adds SAIL, SAIF, and BSAI lock variants absent from the legacy line.
Airtac SI40 Standard Cylinder SI40BX350SH Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX350SH |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX350SH |
| Bore size | Ø40 mm |
| Stroke | 350 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 SAI40BX350SH 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 SAI40BX350SH 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 SI40BX350SH
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×350 | 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 SI40BX350SH Is Used
High-Temp Diversion
Actuates routing gates on hot material conveyors where the Viton H seal and SUS304 rod resist thermal degradation and corrosion.
Extended Reach Ejection
Pushes machined parts out of an enclosed cell using the 350 mm stroke, relying on external guides to absorb side loads.
Vertical Package Lift
Raises lightweight cartons in sorting hubs, safely handling loads near the 32 kg vertical lift capacity at 0.5 MPa.
Replacing the Airtac SI40 Standard Cylinder SI40BX350SH with the SAI40BX350SH
To replace the SI40BX350SH, order the SAI40BX350SH. Verify the ISO 15552 mounting interface, 40 mm bore, 350 mm stroke, G1/4 port, and magnet for CS1-B/DS1-B switches. If downsizing, a 32 mm bore yields 402 N at 0.5 MPa; if upsizing, a 50 mm bore provides 982 N. Because this is a 350 mm stroke, use external guides to prevent rod bending and side-load damage. 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.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX350SH
- ✓ 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 SI40BX350SH FAQ
Yes, the SI40BX350SH is discontinued. The direct replacement is the SAI40BX350SH. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 350 mm stroke, G1/4 port, and mounting interface.
This double-acting cylinder has a G1/4 port. It delivers 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX350SH
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX350SH replacement — usually within 7-8 hours.