This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X395S, 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 SI40X395S
The AirTAC Airtac SI40 Standard Cylinder SI40X395S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 395mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X395S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke395 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X395S
- 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 SI40X395S
The AirTAC SI40X395S is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 395 mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. The direct replacement is the SAI40X395S, matching the exact ISO 15552 mounting interface, bore, stroke, output force, and accessories.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The -S suffix indicates a piston magnet for legacy CS1-B/DS1-B sensors; the SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40X395S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X395S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X395S |
| Bore size | Ø40 mm |
| Stroke | 395 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 SAI40X395S 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 SAI40X395S 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 SI40X395S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×395 | 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 SI40X395S Is Used
Package Diversion
Drives sorting pop-up arms on packaging lines, utilizing the 628 N push force at 0.5 MPa to deflect cartons at high speeds.
Clamp Actuation
Positions workholding clamps on machining fixtures, where the G1/4 port and ISO 15552 mounting ensure rigid, repeatable alignment.
Replacing the Airtac SI40 Standard Cylinder SI40X395S with the SAI40X395S
To replace the SI40X395S, order the SAI40X395S. Confirm the ISO 15552 mounting interface (LB, FA, CA, TC, etc.), the G1/4 port thread (PT, G, or NPT), and the -S magnet requirement. For sizing alternatives, a 32 mm bore yields 402 N push at 0.5 MPa, while a 50 mm bore yields 982 N. Note that a plain cylinder does not hold load on air loss; the 27 mm adjustable cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. At 395 mm stroke, prevent rod bending by guiding the load externally to avoid side-load damage.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X395S
- ✓ 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 SI40X395S FAQ
Yes, the SI40X395S is discontinued. The direct replacement is the SAI40X395S. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 395 mm stroke, G1/4 port, and mounting interface.
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 SAI40X395S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X395S replacement — usually within 7-8 hours.