This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X50SN, 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 SI40X50SN
The AirTAC SI40 Standard Cylinder SI40X50SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 50mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X50SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke50 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X50SN
- 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 SI40X50SN
The AirTAC SI40X50SN is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, 50mm stroke, and a G1/4 air port. Delivering 628N push force at 0.5MPa, it is replaced by the SAI40X50SN direct. The SAI retains identical ISO 15552 mounting dimensions, bore, stroke, and output force, fitting existing fixtures perfectly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family adds SAIL, SAIF, and BSAI variants absent in the SI line. This NBR-sealed unit operates -20 to +70C; a Viton H option raises this to 150C. The -S magnet works with CS1-B/DS1-B switches; the SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40X50SN Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X50SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X50SN |
| Bore size | Ø40 mm |
| Stroke | 50 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 SAI40X50SN 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 SAI40X50SN 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 SI40X50SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×50 | 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 SI40X50SN Is Used
Clamping Mechanisms
Ideal for mid-tier clamping tasks on machining fixtures, utilizing the 628N push force at 0.5MPa to secure components firmly during secondary operations.
Package Diverting
Provides reliable actuation for diverting lightweight to medium packages on material handling lines, benefiting from the 50mm stroke and 30-800mm/s speed range.
Replacing the Airtac SI40 Standard Cylinder SI40X50SN with the SAI40X50SN
To replace the SI40X50SN, order the SAI40X50SN. Verify the ISO 15552 mounting interface, 50mm stroke, G1/4 port (PT/G/NPT), and accessory type. The -S magnet enables CS1-B/DS1-B sensors. For sizing, a 32mm bore yields 402N push at 0.5MPa, while a 50mm bore yields 982N. A plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. The SAIF variant integrates a 4M valve for bores 32-100. Carbon steel, SUS420J2 (A), or SUS304 (B) rods are available.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X50SN
- ✓ 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 SI40X50SN FAQ
Yes, the AirTAC SI40X50SN is discontinued. The direct replacement is the SAI40X50SN. It shares identical ISO 15552 mounting dimensions, 40mm bore, 50mm stroke, G1/4 port, and output force, fitting seamlessly into existing setups.
The 40mm bore features a G1/4 air port, a 16mm rod, and M12x1.25 thread. 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X50SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X50SN replacement — usually within 7-8 hours.