This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X625S, 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 SI40X625S
The AirTAC Airtac SI40 Standard Cylinder SI40X625S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 625mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X625S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke625 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X625S
- 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 SI40X625S
The AirTAC SI40X625S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 625mm stroke. It delivers 628N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI40X625S, matching the interface, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure. It adds SAIL, SAIF, and BSAI variants the SI lacked. A 625mm stroke needs external guides to prevent rod bending.
Airtac SI40 Standard Cylinder SI40X625S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X625S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X625S |
| Bore size | Ø40 mm |
| Stroke | 625 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 SAI40X625S 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 SAI40X625S 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 SI40X625S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×625 | 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 SI40X625S Is Used
Long-Stroke Diversion
Pushes packages across a 625mm transfer lane using 628N push force at 0.5MPa, requiring external guides to prevent rod bending.
Component Ejection
Ejects machined parts from a fixture over a 625mm distance, relying on the 27mm adjustable air cushions to decelerate at stroke end.
Replacing the Airtac SI40 Standard Cylinder SI40X625S with the SAI40X625S
To replace the SI40X625S, order the SAI40X625S, confirming the ISO 15552 mounting interface, 40mm bore, 625mm stroke, G1/4 port, and the -S magnet for CS1-B/DS1-B switches. Sizing both ways: a 50mm bore offers 982N push at 0.5MPa, while dropping to 32mm yields 402N. Because the 625mm stroke exceeds 300mm, use external guides to prevent rod-bending side loads. 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 → SAI40X625S
- ✓ 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 SI40X625S FAQ
Yes, the SI40X625S is discontinued. The direct replacement is the SAI40X625S. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 625mm stroke, 628N force, G1/4 port, and mounting accessories.
The 40mm bore uses a G1/4 port. Force ratings are: 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical max of 128kgf at 1.0MPa. Speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X625S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X625S replacement — usually within 7-8 hours.