This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX30S, 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 SI40BX30S
The AirTAC Airtac SI40 Standard Cylinder SI40BX30S 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 SAI40BX30S, 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 → SAI40BX30S
- 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 SI40BX30S
The AirTAC SI40BX30S is a discontinued double-acting ISO 15552 profile cylinder featuring a SUS304 stainless piston rod and a 30 mm stroke. Delivering 628 N push force at 0.5 MPa through a G1/4 port, it is replaced by the SAI40BX30S. This direct upgrade shares identical mounting and dimensions, fitting existing fixtures perfectly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and longevity. The original -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL, SAIF, and BSAI variants.
Airtac SI40 Standard Cylinder SI40BX30S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX30S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX30S |
| 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 SAI40BX30S 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 SAI40BX30S 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 SI40BX30S
| 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 SI40BX30S Is Used
Stainless Rod Clamping
Short 30 mm stroke with a SUS304 rod provides corrosion-resistant clamping of machined parts in wet machining centers.
Compact Ejection
The 628 N push force at 0.5 MPa is ideal for ejecting small molded components from automated assembly fixtures.
Diverter Actuation
Fast 30 mm travel and integrated magnet for position feedback accurately drive diverter gates on packaging conveyors.
Replacing the Airtac SI40 Standard Cylinder SI40BX30S with the SAI40BX30S
To replace the SI40BX30S, order the SAI40BX30S, confirming the ISO 15552 interface, 40 mm bore, 30 mm stroke, G1/4 port, and -S magnet. The -B rod denotes SUS304 stainless steel for corrosion resistance. If sizing up, the 50 mm bore yields 982 N push at 0.5 MPa; if sizing down, the 32 mm bore yields 402 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock or pilot check valve for load holding. The SAIL or BSAI lock variants are also available in the SAI family.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX30S
- ✓ 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 SI40BX30S FAQ
Yes, the SI40BX30S is discontinued. The direct replacement is the SAI40BX30S, which shares the same ISO 15552 mounting interface, 40 mm bore, 30 mm stroke, G1/4 port, and output force.
The G1/4 port cylinder delivers 628 N push and 528 N pull at 0.5 MPa, 879 N push at 0.7 MPa, and a theoretical maximum of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX30S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX30S replacement — usually within 7-8 hours.