This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X40STC, 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 SI40X40STC
The AirTAC Airtac SI40 Standard Cylinder SI40X40STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 40mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X40STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke40 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X40STC
- 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 SI40X40STC
The AirTAC SI40X40STC is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 40mm stroke, delivering 628N push and 528N pull at 0.5MPa via its G1/4 port. AirTAC replaced this legacy unit with the SAI40X40STC, a direct replacement retaining the exact ISO 15552 mounting interface, TC trunnion mount, M12x1.25 rod thread, and output force.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. Because this SKU includes the -S magnet, it supports legacy CS1-B/DS1-B sensors, while the SAI family uses current AirTAC switches and adds SAIL, SAIF, and BSAI lock variants.
Airtac SI40 Standard Cylinder SI40X40STC Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X40STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X40STC |
| Bore size | Ø40 mm |
| Stroke | 40 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 SAI40X40STC 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 SAI40X40STC 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 SI40X40STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×40 | 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 SI40X40STC Is Used
Compact Clamping
Ideal for holding lighter workpieces in machining fixtures where a 628N push force and short 40mm stroke secure parts without consuming excessive envelope space.
Package Diverting
Provides rapid actuation for diverting small cartons on a conveyor line, utilizing the 30-800mm/s speed range and TC trunnion mount for smooth pivoting action.
Component Insertion
Suitable for pressing bearings or pins into housings on automated assembly lines, taking advantage of the precise 40mm stroke and 528N pull force.
Replacing the Airtac SI40 Standard Cylinder SI40X40STC with the SAI40X40STC
To replace the SI40X40STC, order the SAI40X40STC and verify your ISO 15552 interface, 40mm bore, 40mm stroke, G1/4 port, and TC trunnion mounting accessory. The -S magnet means you can use CS1-B/DS1-B switches on the SI, but plan to migrate to current AirTAC switches for the SAI. When sizing, note the 40mm bore yields 628N push at 0.5MPa; stepping down to a 32mm bore gives 402N, while a 50mm bore provides 982N. A plain cylinder drifts without live air, as the cushion only decelerates near stroke end; for load holding, specify an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X40STC
- ✓ 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 SI40X40STC FAQ
Yes, the AirTAC SI40X40STC is discontinued and end-of-life. The direct replacement is the SAI40X40STC. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 40mm stroke, G1/4 port, TC mount, and output force, so it fits existing fixtures directly.
The 40mm bore operates at 0.15-1.0 MPa with a G1/4 port. It generates 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical maximum force of 128kgf at 1.0MPa. The rod is 16mm with an M12x1.25 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X40STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X40STC replacement — usually within 7-8 hours.