This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X450, 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 SI40X450
The AirTAC Airtac SI40 Standard Cylinder SI40X450 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 450mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X450, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke450 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X450
- 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 SI40X450
The AirTAC SI40X450 is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 450 mm stroke. It delivers 628 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40X450, a direct upgrade retaining the exact interface, bore, stroke, and mounting fixtures.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note this specific SKU lacks a magnet (-S) and cannot accept a CS1-B/DS1-B sensor.
Airtac SI40 Standard Cylinder SI40X450 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X450 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X450 |
| Bore size | Ø40 mm |
| Stroke | 450 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 SAI40X450 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 SAI40X450 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 SI40X450
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×450 | 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 SI40X450 Is Used
Material Diversion
Actuates routing gates on package conveyors where 628 N push force easily deflects standard totes.
Light Lift Stations
Raises 32 kg tooling platens vertically; external linear guides are mandatory for the 450 mm stroke.
Pallet Stops
Deploys mechanical stops at roller bed ends, absorbing kinetic energy via the 27 mm adjustable cushions.
Replacing the Airtac SI40 Standard Cylinder SI40X450 with the SAI40X450
To replace the SI40X450, order the SAI40X450. Verify your ISO 15552 mounting interface (LB, FA, TC, etc.), the G1/4 air port, and the M12x1.25 rod thread. Because this SKU lacks a magnet, it cannot support position sensing; if you need switches, specify the SAI40X450S and use current AirTAC sensors. At 450 mm, this stroke is within the 1200 mm standard max, but you must use external guides to prevent rod bending and side loads. For sizing, a 32 mm bore yields 402 N push at 0.5 MPa, while a 50 mm bore yields 982 N. If you need load holding on air loss, note the cushion only decelerates; use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X450
- ✓ 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 SI40X450 FAQ
Yes, the SI40X450 is discontinued. The direct replacement is the AirTAC SAI40X450. It is dimensionally interchangeable per ISO 15552, matching the 40 mm bore, 450 mm stroke, G1/4 port, and mounting interface, so it fits existing fixtures directly.
This 40 mm bore double-acting cylinder uses a G1/4 air port. At 0.5 MPa it provides 628 N push and 528 N pull force. At 0.7 MPa push is 879 N, and at 0.9 MPa it is 1130 N. The theoretical maximum force is 128 kgf at 1.0 MPa.
Request a Quote for the SAI40X450
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X450 replacement — usually within 7-8 hours.