This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX450, 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 SI40BX450
The AirTAC Airtac SI40 Standard Cylinder SI40BX450 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 SAI40BX450, 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 → SAI40BX450
- 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 SI40BX450
The AirTAC SI40BX450 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 450mm stroke. Featuring a SUS304 stainless steel rod for corrosion resistance, it delivers 628N push force at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40BX450, a direct replacement sharing the exact ISO 15552 mounting interface, bore, stroke, force, and port.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note this specific SKU lacks a magnet, so it cannot accept position sensors.
Airtac SI40 Standard Cylinder SI40BX450 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX450 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX450 |
| 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 SAI40BX450 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 SAI40BX450 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 SI40BX450
| 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 SI40BX450 Is Used
Stainless Rod Diverters
Ideal for food-grade or washdown conveyor routing where the SUS304 rod resists corrosion and the 450mm stroke pushes packages between lanes.
Extended Reach Pushers
Ejects machined parts from an enclosed work area, using the 450mm travel to clear the machine envelope before retraction.
Replacing the Airtac SI40 Standard Cylinder SI40BX450 with the SAI40BX450
To replace the discontinued SI40BX450, order the SAI40BX450. Verify your existing fixture's ISO 15552 mounting interface (such as LB foot or FA flange), the G1/4 port thread (PT/G/NPT), and the 450mm stroke. If sizing up or down, a 32mm bore yields 402N push at 0.5MPa, while a 50mm bore yields 982N. Because this SKU lacks a magnet (-S), it cannot support legacy CS1-B/DS1-B sensors; order a magnet-equipped SAI if position feedback is required. For the 450mm stroke, use an external guide to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; for load holding, specify the SAIL lock, BSAI clamp-lock variant, or an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX450
- ✓ 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 SI40BX450 FAQ
Yes, the AirTAC SI40BX450 is discontinued. The direct replacement is the SAI40BX450. It is dimensionally interchangeable per ISO 15552, retaining the same 40mm bore, 450mm stroke, G1/4 port, and mounting interface, so it fits existing fixtures directly.
This double-acting cylinder uses a G1/4 air port. The thrust 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. It operates at 30-800mm/s with a 27mm adjustable air cushion at both ends.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX450
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX450 replacement — usually within 7-8 hours.