This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X500SN, 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 SI40X500SN
The AirTAC Airtac SI40 Standard Cylinder SI40X500SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 500mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X500SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke500 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X500SN
- 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 SI40X500SN
The AirTAC SI40X500SN is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 500 mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. The direct replacement is the SAI40X500SN, matching the interface, stroke and force. The SAI upgrades the piston seal to two Y-shaped one-way elements for low start-up pressure and long life. The NBR seal suits -20 to +70 C, while a Viton H option extends this to 150 C.
The SAI family also introduces SAIL, SAIF and BSAI lock variants absent from the SI line. Your -S magnet works with legacy CS1-B/DS1-B sensors, though the SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40X500SN Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X500SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X500SN |
| Bore size | Ø40 mm |
| Stroke | 500 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 SAI40X500SN 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 SAI40X500SN 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 SI40X500SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×500 | 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 SI40X500SN Is Used
Long-Stroke Diversion
Pushes packages across a 500 mm transfer gap with a safe 377 N working load, relying on adjustable end cushions to decelerate the carriage.
Vertical Lift Gate
Raises a 32 kg access panel using 0.5 MPa shop air, requiring an external pilot check valve to prevent the load from dropping when air is removed.
Linear Indexing
Shifts a tooling bed 500 mm per cycle, using the -S magnet with legacy CS1-B/DS1-B switches to confirm end-of-travel positioning.
Replacing the Airtac SI40 Standard Cylinder SI40X500SN with the SAI40X500SN
To replace the SI40X500SN, order the SAI40X500SN direct: it preserves the ISO 15552 mounting interface, 40 mm bore, 500 mm stroke, G1/4 port and M12x1.25 rod thread. Retain your -S magnet requirement for position sensing and the -N NBR seal for standard temperatures. When sizing, a 32 mm bore drops force to 402 N push at 0.5 MPa, while a 50 mm bore increases it to 982 N. At 500 mm stroke, prevent rod bending by supporting the load with an external guide to avoid excessive side loads. Note that a plain cylinder drifts on air loss; for load holding, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X500SN
- ✓ 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 SI40X500SN FAQ
Yes, the SI40X500SN is discontinued. The direct replacement is the SAI40X500SN. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 500 mm stroke, 628 N force, G1/4 port and mounting fixtures.
It features a G1/4 port and M12x1.25 rod thread. Force output is 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 maximum of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X500SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X500SN replacement — usually within 7-8 hours.