This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX275, 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 SI40AX275
The AirTAC Airtac SI40 Standard Cylinder SI40AX275 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 275mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX275, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke275 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX275
- 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 SI40AX275
The AirTAC SI40AX275 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 275mm stroke, delivering 628N push force at 0.5MPa. The direct replacement is the SAI40AX275, retaining the exact same interface, G1/4 port, and M12x1.25 rod thread. Because this SKU lacks the -S magnet, it cannot accept a position switch.
The SAI upgrade introduces a two-piece Y-shaped piston seal for lower start-up pressure and longer life, plus a SUS420J2 stainless rod option. Note the cushion only decelerates; it does not hold load.
Airtac SI40 Standard Cylinder SI40AX275 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX275 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX275 |
| Bore size | Ø40 mm |
| Stroke | 275 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 SAI40AX275 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 SAI40AX275 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 SI40AX275
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×275 | 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 SI40AX275 Is Used
Package Diverting
Drives diverting arms on packaging lines where 628N push force reliably redirects cartons at speed.
Pallet Stopping
Acts as a pneumatic stop gate for lightweight pallets, using the 275mm stroke to clear the conveyor path.
Clamp Actuation
Secures workpieces during machining, providing stable clamping up to 1130N at 0.9MPa operating pressure.
Replacing the Airtac SI40 Standard Cylinder SI40AX275 with the SAI40AX275
To replace the SI40AX275, order the SAI40AX275. Verify your ISO 15552 mounting fixtures (LB, FA, TC, etc.), the G1/4 air port, and the 275mm stroke. This non-magnetic unit cannot support sensors; if sensing is needed, select an SAI40X275S and use current AirTAC switches. For load holding on air loss, add an external pilot check valve or explore the SAIL/BSAI lock variants, as cushions only decelerate. At 275mm stroke, guide side-loads to prevent rod bending. If 628N at 0.5MPa is insufficient, step up to the 50mm bore (982N); if over-specified, the 32mm bore (402N) fits.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX275
- ✓ 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 SI40AX275 FAQ
Yes, the SI40AX275 is discontinued. The direct replacement is the SAI40AX275. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 275mm stroke, 628N force, G1/4 port, and mounting accessories.
The G1/4 port feeds a 40mm bore yielding 628N push and 528N pull at 0.5MPa. At 0.7MPa push is 879N, and 1130N at 0.9MPa. The theoretical maximum force is 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX275
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX275 replacement — usually within 7-8 hours.