This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X510S, 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 SI40X510S
The AirTAC Airtac SI40 Standard Cylinder SI40X510S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 510mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X510S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke510 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X510S
- 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 SI40X510S
The AirTAC SI40X510S is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 510 mm stroke. It delivers 628 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40X510S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, and output force.
The SAI upgrade features a redesigned piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also introduces SAIL, SAIF, and BSAI lock variants absent in the SI line, and your existing CS1-B/DS1-B legacy sensors fit the -S magnet groove.
Airtac SI40 Standard Cylinder SI40X510S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X510S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X510S |
| Bore size | Ø40 mm |
| Stroke | 510 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 SAI40X510S 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 SAI40X510S 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 SI40X510S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×510 | 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 SI40X510S Is Used
Long-Stroke Diversion
Pushes packages across transfer lines with a 510 mm reach, utilizing the 628 N push force at 0.5 MPa to overcome guide friction.
Component Ejection
Ejects machined parts from a fixture over a long distance, relying on adjustable 27 mm air cushions to decelerate at stroke end.
Replacing the Airtac SI40 Standard Cylinder SI40X510S with the SAI40X510S
To replace the SI40X510S, order the SAI40X510S. Verify your ISO 15552 mounting accessory (LB, FA, or TC), the G1/4 port, and the M12x1.25 rod thread. The SAI drops directly into existing fixtures. If you need more force, the neighboring 50 mm bore provides 982 N push at 0.5 MPa; if less is required, the 32 mm bore offers 402 N. Because this is a 510 mm stroke, use an external guide to prevent rod bending and side-load damage. A plain cylinder does not hold load on air loss—the cushion only decelerates. For load holding, use an external pilot check valve or the SAIL lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X510S
- ✓ 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 SI40X510S FAQ
Yes, the SI40X510S is discontinued. The direct replacement is the SAI40X510S. It shares the same ISO 15552 mounting interface, 40 mm bore, 510 mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
This 40 mm bore cylinder features a G1/4 air port and M12x1.25 rod thread. It delivers 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 max of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X510S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X510S replacement — usually within 7-8 hours.