This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40AX400SH, 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 SI40AX400SH
The AirTAC Airtac SI40 Standard Cylinder SI40AX400SH is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 400mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40AX400SH, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke400 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40AX400SH
- 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 SI40AX400SH
The AirTAC SI40AX400SH is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 400mm stroke, and a SUS420J2 stainless steel rod. It delivers 628 N push and 528 N pull at 0.5 MPa through a G1/4 port, with a Viton H seal enabling 0-150 C operation. The direct replacement is the SAI40AX400SH, matching the interface, force, and stroke exactly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and longevity. The original -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40AX400SH Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40AX400SH |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40AX400SH |
| Bore size | Ø40 mm |
| Stroke | 400 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 SAI40AX400SH 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 SAI40AX400SH 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 SI40AX400SH
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×400 | 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 SI40AX400SH Is Used
High-Temp Diversion
Actuating diverters on warm material conveyors where the Viton H seal survives 0-150 C ambient heat and the 628 N force easily pushes standard packages.
Stainless Rod Ejection
Ejecting machined parts from coolant-washed fixtures using the SUS420J2 rod for corrosion resistance over the 400mm travel.
Replacing the Airtac SI40 Standard Cylinder SI40AX400SH with the SAI40AX400SH
To replace the SI40AX400SH, order the SAI40AX400SH. Confirm the ISO 15552 mounting interface, 40mm bore, 400mm stroke, G1/4 port, and your specific mounting accessory. The -A rod is SUS420J2 stainless steel, the -H seal is Viton for 0-150 C heat, and -S provides the magnet for CS1-B/DS1-B switches. For sizing, a 32mm bore offers 402 N push at 0.5 MPa, while a 50mm bore yields 982 N; alternatively, raising pressure to 0.7 MPa on the 40mm gives 879 N. Because the 400mm stroke exceeds 300mm, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40AX400SH
- ✓ 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 SI40AX400SH FAQ
Yes, the SI40AX400SH is discontinued. The direct replacement is the SAI40AX400SH. It is dimensionally interchangeable per ISO 15552, retaining the same 40mm bore, 400mm stroke, 628 N force, G1/4 port, and mounting interface.
The G1/4 port bore delivers a push of 628 N and pull of 528 N at 0.5 MPa. At 0.7 MPa the push is 879 N, and at 0.9 MPa it is 1130 N. The theoretical maximum force is 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40AX400SH
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40AX400SH replacement — usually within 7-8 hours.