This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X75STC, 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 SI40X75STC
The AirTAC Airtac SI40 Standard Cylinder SI40X75STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 75mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X75STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke75 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X75STC
- 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 SI40X75STC
The AirTAC SI40X75STC is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 75mm stroke. Delivering 628N push force at 0.5MPa via a G1/4 port, it is replaced by the direct replacement SAI40X75STC. The SAI matches the exact ISO 15552 mounting interface, TC trunnion, and output force.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked. Your -S magnet works with legacy CS1-B/DS1-B sensors.
Airtac SI40 Standard Cylinder SI40X75STC Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X75STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X75STC |
| Bore size | Ø40 mm |
| Stroke | 75 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 SAI40X75STC 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 SAI40X75STC 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 SI40X75STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×75 | 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 SI40X75STC Is Used
Component Ejection
Pushes machined parts out of a CNC fixture using 628N of force, relying on the 75mm stroke for rapid extraction.
Sorter Diverting
Actuates a routing gate on a packaging line, where the TC trunnion handles the lateral pivot stress efficiently.
Light Pallet Stops
Deploys a 32kg vertical lift stop block to halt empty pallets on a gravity roller conveyor before a transfer station.
Replacing the Airtac SI40 Standard Cylinder SI40X75STC with the SAI40X75STC
To replace this SI40X75STC, order the SAI40X75STC. Confirm the ISO 15552 TC trunnion mount, 75mm stroke, G1/4 port, and the -S magnet for CS1-B/DS1-B switches. For sizing alternatives, a 32mm bore yields 402N push at 0.5MPa, while a 50mm bore yields 982N. This plain cylinder does not hold load without live air; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. Rod material options include carbon steel, SUS420J2 (A), or SUS304 (B).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X75STC
- ✓ 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 SI40X75STC FAQ
Yes, the SI40X75STC is discontinued. The direct replacement is the SAI40X75STC. It shares the same ISO 15552 mounting interface, 40mm bore, 75mm stroke, G1/4 port, and TC trunnion, fitting existing fixtures perfectly.
It features a G1/4 air port. The force ratings are: 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical maximum of 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X75STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X75STC replacement — usually within 7-8 hours.