This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X660S, 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 SI40X660S
The AirTAC Airtac SI40 Standard Cylinder SI40X660S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 660mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X660S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke660 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X660S
- 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 SI40X660S
The AirTAC SI40X660S is a discontinued double-acting ISO 15552 profile cylinder. It delivers 628 N push at 0.5 MPa through a 40 mm bore and 660 mm stroke, featuring a G1/4 port and M12x1.25 rod thread. AirTAC replaced this legacy unit with the SAI40X660S, a direct upgrade retaining the exact ISO 15552 mounting interface, output force, and dimensions.
The SAI replacement introduces an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and extended life. The SAI family also adds SAIL, SAIF, and BSAI lock variants absent in the SI line. Your -S suffix denotes a piston magnet for legacy CS1-B/DS1-B sensors.
Airtac SI40 Standard Cylinder SI40X660S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X660S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X660S |
| Bore size | Ø40 mm |
| Stroke | 660 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 SAI40X660S 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 SAI40X660S 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 SI40X660S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×660 | 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 SI40X660S Is Used
Carton Diverting
Drives diverting arms on packaging lines, utilizing the 660 mm stroke to push standard cartons cleanly off the main conveyor belt.
Pallet Push-off
Acts as a push-off mechanism in end-of-line palletizing, moving lightweight product stacks onto waiting pallets without overpowering the load.
Vertical Lowering
Lowers light fixture components vertically, where the 32 kg safe vertical lift capacity matches the payload requirements safely.
Replacing the Airtac SI40 Standard Cylinder SI40X660S with the SAI40X660S
To replace the SI40X660S, order the SAI40X660S. Verify your ISO 15552 mounting accessories (LB, FA, TC, etc.), the G1/4 air port, and the M12x1.25 rod thread. The -S magnet allows current AirTAC switches to function. For sizing, this 40 mm bore yields 628 N push at 0.5 MPa; if less force is needed, a 32 mm bore gives 402 N, while a 50 mm bore provides 982 N. Because the stroke is 660 mm, use an external guide to prevent rod bending and side-load damage. Note that a standard cylinder drifts without live air; for load holding, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X660S
- ✓ 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 SI40X660S FAQ
Yes, the AirTAC SI40X660S is discontinued. The direct replacement is the SAI40X660S. It features the same ISO 15552 mounting interface, 40 mm bore, 660 mm stroke, G1/4 port, and output force, fitting directly into existing fixtures.
This 40 mm bore cylinder uses a G1/4 air port. It generates 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 SAI40X660S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X660S replacement — usually within 7-8 hours.