This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX270, 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 SI40AX270
The AirTAC Airtac SI40 Standard Cylinder SI40AX270 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 270mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX270, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke270 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX270
- 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 SI40AX270
The AirTAC SI40AX270 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 270mm stroke. It delivers 628N push force at 0.5MPa and features a G1/4 air port. The direct replacement is the SAI40AX270, matching the interface, force, and port exactly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure. This SKU has a SUS420J2 stainless rod and no magnet, so it cannot take a sensor. For safe sizing, expect a 377N working load (60% of push) and a 32kg vertical lift capacity.
Airtac SI40 Standard Cylinder SI40AX270 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX270 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX270 |
| Bore size | Ø40 mm |
| Stroke | 270 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 SAI40AX270 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 SAI40AX270 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 SI40AX270
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×270 | 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 SI40AX270 Is Used
Package Diverting
Ideal for pushing medium-weight cartons off a belt line, utilizing the 628N push force at 0.5MPa to reliably actuate routing gates without lag.
Clamp Actuation
Provides secure holding pressure for mid-sized aluminum extrusion fixtures, taking advantage of the 270mm stroke to clear the work area fully.
Replacing the Airtac SI40 Standard Cylinder SI40AX270 with the SAI40AX270
To replace the SI40AX270, order the SAI40AX270 to retain the exact ISO 15552 mounting interface, 40mm bore, 270mm stroke, G1/4 port, and M12x1.25 thread. Because this stroke is 270mm, ensure your guide handles side loads to prevent rod bending. If you need position sensing, this no-magnet SKU cannot accept a switch; you must select an SAI variant with the S suffix for CS1-B/DS1-B or current switches. For load holding on air loss, note that the cushion only decelerates; use an external pilot check valve or the SAIL/BSAI lock variants. If sizing up or down, a 50mm bore offers 982N push at 0.5MPa, while a 32mm bore provides 402N.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX270
- ✓ 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 SI40AX270 FAQ
Yes, the SI40AX270 is discontinued. The direct replacement is the SAI40AX270. It is dimensionally interchangeable per ISO 15552, retaining the same 40mm bore, 270mm stroke, force, G1/4 port, and mounting interface.
The bore is 40mm with a G1/4 air 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 128kgf at 1.0MPa. Operating speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX270
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX270 replacement — usually within 7-8 hours.