This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X740S, 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 SI40X740S
The AirTAC Airtac SI40 Standard Cylinder SI40X740S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 740mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X740S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke740 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X740S
- 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 SI40X740S
The AirTAC SI40X740S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 740mm stroke. Generating 628N push force at 0.5MPa, it is directly replaced by the SAI40X740S. This direct upgrade shares the same G1/4 port, M12x1.25 rod thread, and mounting interface.
The SAI features an upgraded piston seal with two Y-shaped elements for low start-up pressure. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked. Your -S magnet works with legacy CS1-B/DS1-B sensors.
Airtac SI40 Standard Cylinder SI40X740S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X740S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X740S |
| Bore size | Ø40 mm |
| Stroke | 740 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 SAI40X740S 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 SAI40X740S 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 SI40X740S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×740 | 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 SI40X740S Is Used
Long-Stroke Diversion
Drives sorting paddles across conveyor belts, utilizing the full 740mm travel to reroute packages smoothly at production line speeds.
Vertical Material Lift
Raises lightweight tote bins up to 32kg in pick modules, relying on the 628N thrust class to elevate goods between ergonomic working tiers.
Actuator Positioning
Shifts secondary tooling carriages in and out of the machining zone, taking advantage of the adjustable 27mm air cushions to decelerate at stroke ends.
Replacing the Airtac SI40 Standard Cylinder SI40X740S with the SAI40X740S
To replace the SI40X740S, order the SAI40X740S. Verify your ISO 15552 mounting accessories (LB, FA, TC, etc.), the G1/4 port, and the -S magnet for CS1-B/DS1-B switches. If you need more force, the 50mm bore offers 982N push at 0.5MPa; if less is acceptable, the 32mm bore provides 402N. Because 740mm exceeds 300mm, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X740S
- ✓ 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 SI40X740S FAQ
Yes, the SI40X740S is discontinued. The direct replacement is the SAI40X740S. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 740mm stroke, 628N force, G1/4 port, and mounting fixtures.
The 40mm bore has a G1/4 air port. At 0.5MPa it provides 628N push and 528N pull. At 0.7MPa push is 879N, at 0.9MPa it is 1130N, and the theoretical maximum is 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X740S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X740S replacement — usually within 7-8 hours.