This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X35, 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 SI40X35
The AirTAC Airtac SI40 Standard Cylinder SI40X35 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 SAI40X35, 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 → SAI40X35
- 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 SI40X35
The AirTAC SI40X35 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 35mm stroke. It delivers 628N push force at 0.5MPa through a G1/4 port. The direct replacement is the SAI40X35, matching the exact bore, stroke, force, port, and ISO 15552 mounting interface for existing fixtures.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. This SKU lacks a magnet (-S) and cannot take a sensor. For high heat, Viton H seals raise the temperature limit to 150C.
Airtac SI40 Standard Cylinder SI40X35 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X35 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X35 |
| 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 SAI40X35 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 SAI40X35 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 SI40X35
| 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 SI40X35 Is Used
Short-Stroke Clamping
Ideal for holding light metal or plastic parts in machining fixtures, utilizing the 628N push force over a compact 35mm travel.
Package Diverting
Provides rapid actuation for sorting small packages on a line, operating efficiently at speeds between 30-800 mm/s.
Ejector Mechanism
Delivers precise 35mm ejection strokes for small stamped or molded components without consuming excessive machine space.
Replacing the Airtac SI40 Standard Cylinder SI40X35 with the SAI40X35
To replace the SI40X35, order the SAI40X35. Verify your ISO 15552 mounting accessory (LB, FA, TC), the G1/4 air port, and the M12x1.25 rod thread. Because this specific SKU has no magnet, it cannot accept CS1-B/DS1-B switches. For sizing, the 40mm bore yields 628N push at 0.5MPa; if less force is needed, a 32mm bore gives 402N. If holding a load, note the air cushion only decelerates; use an external pilot check valve or the SAIL lock variant to prevent drift.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X35
- ✓ 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 SI40X35 FAQ
Yes, the SI40X35 is discontinued. The direct replacement is the AirTAC SAI40X35. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 35mm stroke, 628N force, G1/4 port, and mounting interface.
The 40mm bore uses a G1/4 port. Force output is 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical max of 128 kgf at 1.0 MPa.
Request a Quote for the SAI40X35
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X35 replacement — usually within 7-8 hours.