This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X40FA, 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 SI50 Standard Cylinder SI50X40FA
The AirTAC Airtac SI50 Standard Cylinder SI50X40FA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 40mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X40FA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke40 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X40FA
- 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 SI50 Standard Cylinder SI50X40FA
The AirTAC SI50X40FA is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 40mm stroke. It delivers 982 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50X40FA, a direct sharing the exact FA flange mount, bore, stroke, and output force.
The SAI upgrade features a revised piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Because this specific SKU lacks the -S magnet, it cannot accept position sensors.
Airtac SI50 Standard Cylinder SI50X40FA Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X40FA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X40FA |
| Bore size | Ø50 mm |
| Stroke | 40 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M16×1.5 |
| 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, 30 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI50X40FA carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø50mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 982 N | 825 N |
| 0.7 MPa | 1374 N | — |
| Max (@1.0 MPa) | 200 kgf | |
The SAI50X40FA produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI50 Standard Cylinder SI50X40FA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×40 | 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 SI50 Standard Cylinder SI50X40FA Is Used
Short-Stroke Clamping
Applies 982 N of push force at 0.5 MPa to secure mid-weight workpieces during machining operations.
Package Diverting
Uses the 40mm stroke to push parcels between adjacent conveyor lanes in material handling lines.
Gate Actuation
Drives small access gates or doors on automated machinery using the FA flange mounting interface.
Replacing the Airtac SI50 Standard Cylinder SI50X40FA with the SAI50X40FA
To replace the SI50X40FA, order the SAI50X40FA. Verify the ISO 15552 FA flange interface, 50mm bore, 40mm stroke, and G1/4 port. If sizing up or down, note the 63mm bore yields 1559 N push at 0.5 MPa, while the 40mm bore yields 628 N. This non-magnetized SKU cannot fit CS1-B/DS1-B sensors; order an -S variant if sensing is needed. The air cushion only decelerates the load; it does not hold position on air loss. For secure load holding, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X40FA
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI50 Standard Cylinder SI50X40FA FAQ
Yes, the SI50X40FA is discontinued. The direct replacement is the SAI50X40FA, which maintains the same ISO 15552 FA flange mounting, 50mm bore, 40mm stroke, and G1/4 port for a seamless fixture upgrade.
The 50mm bore uses a G1/4 port. It generates 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a theoretical maximum of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X40FA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X40FA replacement — usually within 7-8 hours.