This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX950, 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 SI40BX950
The AirTAC Airtac SI40 Standard Cylinder SI40BX950 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 950mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX950, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke950 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX950
- 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 SI40BX950
The AirTAC SI40BX950 is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 950mm stroke, and a SUS304 stainless steel rod. Delivering 628 N push force at 0.5 MPa, it is replaced by the SAI40BX950. This direct upgrade shares the exact ISO 15552 mounting interface, bore, stroke, output force, G1/4 port, and M12x1.25 rod thread, fitting existing fixtures perfectly.
The SAI upgrade utilizes a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note that this non-magnet version cannot accept position sensors, and a plain cylinder requires external guides for its 950mm stroke to prevent rod bending.
Airtac SI40 Standard Cylinder SI40BX950 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX950 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX950 |
| Bore size | Ø40 mm |
| Stroke | 950 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 SAI40BX950 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 SAI40BX950 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 SI40BX950
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×950 | 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 SI40BX950 Is Used
Long-Stroke Diversion
Actuates routing gates on packaging lines over a 950mm span, utilizing the SUS304 rod for washdown corrosion resistance.
Pneumatic Ejection
Pushes sorted parts out of a machining zone, requiring external guide rails to support the extended 950mm rod length.
Replacing the Airtac SI40 Standard Cylinder SI40BX950 with the SAI40BX950
To replace the discontinued SI40BX950, order the SAI40BX950, confirming the ISO 15552 mounting interface, 40mm bore, 950mm stroke, G1/4 port, and SUS304 stainless rod. Because this is a non-magnet SKU, it cannot support legacy CS1-B/DS1-B sensors; add a magnet (-S) if position feedback is required. For sizing, the 628 N push force at 0.5 MPa handles moderate loads, but neighboring bores offer alternatives (32mm yields 402 N; 50mm yields 982 N). At 950mm, external guides are mandatory to prevent rod bending under side loads. A plain cylinder drifts on air loss; for load holding, use an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX950
- ✓ 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 SI40BX950 FAQ
Yes, the SI40BX950 is discontinued. The direct replacement is the SAI40BX950. It is dimensionally interchangeable per ISO 15552, retaining the same 40mm bore, 950mm stroke, force, G1/4 port, and mounting interface.
The G1/4 port bore delivers a push force of 628 N and pull of 528 N at 0.5 MPa, 879 N push at 0.7 MPa, 1130 N push at 0.9 MPa, and a theoretical max of 128 kgf at 1.0 MPa. It operates at 30-800 mm/s with a 27mm adjustable cushion.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX950
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX950 replacement — usually within 7-8 hours.