This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X140S, 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 SI40X140S
The AirTAC Airtac SI40 Standard Cylinder SI40X140S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 140mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X140S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke140 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X140S
- 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 SI40X140S
The AirTAC SI40X140S is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 140mm stroke, and a G1/4 air port. Delivering 628 N push force at 0.5 MPa, it is directly replaced by the current-production SAI40X140S. This direct upgrade shares the exact same ISO 15552 mounting interface, bore, stroke, output force, port size, and accessories, fitting existing fixtures perfectly.
The SAI replacement introduces an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SI40X140S includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI family also adds SAIL, SAIF, and BSAI lock or valve variants the original SI lacked.
Airtac SI40 Standard Cylinder SI40X140S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X140S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X140S |
| Bore size | Ø40 mm |
| Stroke | 140 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 SAI40X140S 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 SAI40X140S 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 SI40X140S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×140 | 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 SI40X140S Is Used
Clamp Actuation
Secures aluminium extrusions or light workpieces during machining, utilising the 32 kg vertical lift capacity.
Gate Positioning
Indexes sorting gates and stops on material handling conveyors with reliable double-acting motion.
Replacing the Airtac SI40 Standard Cylinder SI40X140S with the SAI40X140S
To replace the discontinued SI40X140S, order the SAI40X140S. Verify your ISO 15552 mounting interface (LB, FA, TC, etc.), the 40mm bore, 140mm stroke, G1/4 port thread (PT, G, or NPT), and the -S magnet requirement for CS1-B/DS1-B switches. If you need more force, the neighbouring 50mm bore yields 982 N push at 0.5 MPa; if less is required, the 32mm bore provides 402 N. Because this is a 140mm stroke, ensure adequate guidance to prevent rod bending under side loads. A plain cylinder does not hold load without live air; the cushion only decelerates. For load holding on air loss, use an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X140S
- ✓ 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 SI40X140S FAQ
Yes, the SI40X140S is discontinued. The direct replacement is the AirTAC SAI40X140S. It shares the same ISO 15552 mounting interface, 40mm bore, 140mm stroke, output force, and G1/4 port, dropping directly into existing fixtures.
The G1/4 port bore delivers a push force of 628 N and a pull force of 528 N at 0.5 MPa. At 0.7 MPa push is 879 N, at 0.9 MPa it is 1130 N, and the theoretical maximum is 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X140S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X140S replacement — usually within 7-8 hours.