This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX750, 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 SI40AX750
The AirTAC Airtac SI40 Standard Cylinder SI40AX750 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 750mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX750, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke750 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX750
- 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 SI40AX750
The AirTAC SI40AX750 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 750mm stroke. Built with an extruded aluminum barrel and a SUS420J2 stainless piston rod, it delivers 628 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40AX750, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke, and force ratings.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note that this specific SKU lacks a magnet and cannot accept position sensors, though the broader SAI family introduces SAIL, SAIF, and BSAI lock and valve variants absent from the SI line.
Airtac SI40 Standard Cylinder SI40AX750 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX750 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX750 |
| Bore size | Ø40 mm |
| Stroke | 750 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 SAI40AX750 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 SAI40AX750 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 SI40AX750
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×750 | 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 SI40AX750 Is Used
Long-Stroke Diversion
Ideal for pushing packages across a 750mm transit gap on packaging lines where the 628 N force easily overcomes friction.
Elevated Lowering
Controls the descent of 32 kg vertical loads using adjustable air cushions, requiring external guides for the long rod.
Corrosive Testing
The SUS420J2 stainless rod performs reliably in damp test chambers, operating at 30-800 mm/s without rusting.
Replacing the Airtac SI40 Standard Cylinder SI40AX750 with the SAI40AX750
To replace the SI40AX750, order the SAI40AX750. Verify the ISO 15552 mounting interface, the 40mm bore, the 750mm stroke, the G1/4 port, and your mounting accessory. Because this SKU lacks a magnet (-S), it cannot support legacy CS1-B/DS1-B sensors; order a magnet-equipped SAI if position detection is required. When sizing, a 32mm bore yields 402 N push at 0.5 MPa, while a 50mm bore yields 982 N. For this 750mm stroke, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for load holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX750
- ✓ 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 SI40AX750 FAQ
Yes, the SI40AX750 is discontinued. The direct replacement is the SAI40AX750. It shares the identical ISO 15552 mounting interface, 40mm bore, 750mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
The 40mm bore uses a G1/4 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 max of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX750
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX750 replacement — usually within 7-8 hours.