This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X90STC, 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 SI40X90STC
The AirTAC Airtac SI40 Standard Cylinder SI40X90STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 90mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X90STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke90 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X90STC
- 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 SI40X90STC
The AirTAC SI40X90STC is a discontinued double-acting ISO 15552 profile cylinder featuring a 40 mm bore, 90 mm stroke, and a TC trunnion mount. It delivers 628 N of push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40X90STC, a direct upgrade sharing the exact same interface, bore, stroke, output force, and mounting dimensions.
The SAI replacement incorporates an upgraded piston seal utilizing two Y-shaped one-way elements for low start-up pressure and extended life. It also expands your options with SAIL, SAIF, and BSAI variants the original SI lacked. The -S suffix denotes a piston magnet for legacy CS1-B/DS1-B sensors, while seal options include Viton H for high-temperature environments.
Airtac SI40 Standard Cylinder SI40X90STC Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X90STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X90STC |
| Bore size | Ø40 mm |
| Stroke | 90 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 SAI40X90STC 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 SAI40X90STC 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 SI40X90STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×90 | 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 SI40X90STC Is Used
Package Diversion
Ideal for actuating routing gates on packaging lines, utilizing the 90 mm stroke and 628 N push force to redirect cartons smoothly.
Clamp Actuation
Provides reliable clamping pressure for light machining fixtures, where the TC trunnion mount accommodates slight alignment shifts.
Stopper Arm Control
Deploys pneumatic stopper arms on roller conveyors, safely halting items up to 32 kg using the integrated magnet for position feedback.
Replacing the Airtac SI40 Standard Cylinder SI40X90STC with the SAI40X90STC
To replace the discontinued SI40X90STC, order the SAI40X90STC. Confirm your ISO 15552 TC trunnion mounting interface, 40 mm bore, 90 mm stroke, G1/4 port, and the -S magnet requirement. The direct SAI family maintains the same 30-800 mm/s speed and 27 mm adjustable cushion. If you need more force, the neighboring 50 mm bore offers 982 N push at 0.5 MPa; if less is required, the 32 mm bore provides 402 N. Remember that a standard cylinder drifts on air loss because the cushion only decelerates near stroke end. For load holding, use an external pilot check valve or switch to the SAIL lock variant. The SAI also adds the SAIF integrated valve option for bores 32-100.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X90STC
- ✓ 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 SI40X90STC FAQ
Yes, the AirTAC SI40X90STC is discontinued. The direct replacement is the SAI40X90STC. It is dimensionally interchangeable per ISO 15552, maintaining the same 40 mm bore, 90 mm stroke, G1/4 port, and TC mounting interface.
The bore is 40 mm with a G1/4 air port. Force ratings are: 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 of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X90STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X90STC replacement — usually within 7-8 hours.