This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X205S, 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 SI50X205S
The AirTAC SI50 Standard Cylinder SI50X205S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 205mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X205S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke205 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X205S
- 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 SI50X205S
The AirTAC SI50X205S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 205 mm stroke. It delivers 982 N push force at 0.5 MPa via a G1/4 port. Because 205 mm is a non-standard stroke, it was supplied as a special build. AirTAC replaced this legacy unit with the SAI50X205S, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke, force and port size.
The SAI replacement features an upgraded piston seal using two Y-shaped one-way elements for low start-up pressure and long life. It also introduces lock and valve variants the SI lacked, like the SAIL and BSAI series. The built-in magnet on this -S model supports CS1-B/DS1-B sensors, while the SAI uses current AirTAC switches.
Airtac SI50 Standard Cylinder SI50X205S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X205S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X205S |
| Bore size | Ø50 mm |
| Stroke | 205 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 SAI50X205S 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 SAI50X205S 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 SI50X205S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×205 | 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 SI50X205S Is Used
Package Diverting
Pushes medium-weight cartons off a main conveyor line using 982 N of thrust at 0.5 MPa.
Pallet Stop Gate
Raises and lowers a physical stop gate to control pallet flow on a gravity roller bed.
Replacing the Airtac SI50 Standard Cylinder SI50X205S with the SAI50X205S
To replace the SI50X205S, order the SAI50X205S. Confirm your ISO 15552 mounting interface (LB, FA, TC, etc.), the G1/4 port thread (PT, G or NPT), and the M16x1.5 rod-end thread. If you need to adjust force, the neighboring 40 mm bore gives 628 N push at 0.5 MPa, while the 63 mm bore yields 1559 N. Because this is a 205 mm stroke, add external guide rails to prevent rod bending under side loads. 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 held loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X205S
- ✓ 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 SI50X205S FAQ
Yes, the SI50X205S is discontinued. The direct replacement is the AirTAC SAI50X205S. It shares the identical ISO 15552 mounting interface, 50 mm bore, 205 mm stroke, 982 N force, and G1/4 port, fitting existing fixtures perfectly.
The 50 mm bore uses a G1/4 air port. At 0.5 MPa it provides 982 N push and 825 N pull force. At 0.7 MPa push is 1374 N, and at 0.9 MPa it is 1767 N. The theoretical maximum force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X205S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X205S replacement — usually within 7-8 hours.