This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X445S, 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 SI40X445S
The AirTAC Airtac SI40 Standard Cylinder SI40X445S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 445mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X445S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke445 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X445S
- 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 SI40X445S
The AirTAC SI40X445S is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore and 445mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40X445S, a direct upgrade retaining the exact interface, bore, stroke, and mounting hardware.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also introduces SAIL, SAIF, and BSAI lock variants absent in the original SI line.
Airtac SI40 Standard Cylinder SI40X445S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X445S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X445S |
| Bore size | Ø40 mm |
| Stroke | 445 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 SAI40X445S 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 SAI40X445S 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 SI40X445S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×445 | 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 SI40X445S Is Used
Package Diversion
Pushes lightweight totes at 30-800 mm/s on packaging lines, utilizing the 445mm stroke to clear adjacent conveyor lanes.
Component Ejection
Ejects machined parts from a fixture using 628 N of push force, with the magnet enabling end-of-stroke confirmation.
Pallet Stopper
Acts as a pneumatic stop for incoming pallets, safely decelerating loads using the adjustable 27mm air cushions.
Replacing the Airtac SI40 Standard Cylinder SI40X445S with the SAI40X445S
To replace the SI40X445S, order the SAI40X445S and verify your ISO 15552 mounting interface, G1/4 port thread (PT/G/NPT), and the -S magnet for CS1-B/DS1-B sensors. When sizing, a 50mm bore offers 982 N push at 0.5 MPa, while a 32mm bore provides 402 N. Because the 445mm stroke exceeds 300mm, use an external guide to prevent rod bending and side-load wear. Note that standard cylinders do not hold load without live air; for load holding on pressure loss, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X445S
- ✓ 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 SI40X445S FAQ
Yes, the SI40X445S is discontinued. The direct replacement is the AirTAC SAI40X445S. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 445mm stroke, G1/4 port, and mounting interface.
It uses a G1/4 air port. The 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 max of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X445S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X445S replacement — usually within 7-8 hours.