This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X35H, 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 SI40X35H
The AirTAC SI40 Standard Cylinder SI40X35H is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 35mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X35H, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke35 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X35H
- 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 SI40X35H
The AirTAC SI40X35H is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 35 mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. The direct replacement is the SAI40X35H, which matches the exact bore, stroke, force, and ISO 15552 mounting interface.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SI40X35H uses a Viton H seal for 0-150 C high-temp environments. Without a -S magnet, it cannot accept a sensor.
Airtac SI40 Standard Cylinder SI40X35H Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X35H |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X35H |
| Bore size | Ø40 mm |
| Stroke | 35 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 SAI40X35H 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 SAI40X35H 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 SI40X35H
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×35 | 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 SI40X35H Is Used
High-Temp Clamping
Short-stroke clamping of parts near heat zones or ovens, utilizing the Viton H seal to withstand 0-150 C ambient temperatures.
Ejector Mechanism
Providing 628 N push force at 0.5 MPa to eject small molded components or machined parts from a fixture.
Gate Diverting
Actuating light-duty flow gates or diverter arms where a compact 35 mm stroke and 16 mm rod are sufficient.
Replacing the Airtac SI40 Standard Cylinder SI40X35H with the SAI40X35H
To replace the SI40X35H, order the SAI40X35H. Confirm the ISO 15552 mounting interface, 40 mm bore, 35 mm stroke, G1/4 port (PT/G/NPT thread), and your specific mounting accessory. Because this SKU lacks a -S magnet, it cannot take a CS1-B/DS1-B sensor; order a magnet-equipped SAI if position sensing is needed. For sizing, the 32 mm bore offers 402 N push at 0.5 MPa, while the 50 mm bore offers 982 N. If you need load holding on air loss, note that a plain cylinder drifts; the cushion only decelerates. Use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X35H
- ✓ 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 SI40X35H FAQ
Yes, the SI40X35H is discontinued. The direct replacement is the SAI40X35H. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 35 mm stroke, 628 N force, G1/4 port, and mounting interface.
This double-acting cylinder has a G1/4 port. Force ratings are: push 628 N and pull 528 N at 0.5 MPa, push 879 N at 0.7 MPa, push 1130 N at 0.9 MPa, and a theoretical max of 128 kgf at 1.0 MPa.
Request a Quote for the SAI40X35H
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X35H replacement — usually within 7-8 hours.