This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X300SFTC, 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 SI50X300SFTC
The AirTAC Airtac SI50 Standard Cylinder SI50X300SFTC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 300mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X300SFTC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke300 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X300SFTC
- 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 SI50X300SFTC
The AirTAC SI50X300SFTC is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 300mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50X300SFTC, matching the bore, stroke, force, port, and FTC trunnion mount.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. The SAI family adds SAIL and BSAI lock variants the SI lacked. This -S SKU supports CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X300SFTC Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X300SFTC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X300SFTC |
| Bore size | Ø50 mm |
| Stroke | 300 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 SAI50X300SFTC 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 SAI50X300SFTC 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 SI50X300SFTC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×300 | 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 SI50X300SFTC Is Used
Material Diversion
Actuates sorting gates on conveyor lines, utilizing the 982N push force to reliably redirect heavy packages along 300mm travel paths.
Pallet Handling
Drives lifting mechanisms in automated storage systems where the FTC trunnion mount accommodates pivoting movements during pallet transfer.
Clamp Actuation
Secures mid-weight workpieces in CNC machining fixtures, providing stable 825N pull force for through-feed milling operations.
Replacing the Airtac SI50 Standard Cylinder SI50X300SFTC with the SAI50X300SFTC
To replace the SI50X300SFTC, order the SAI50X300SFTC to retain the exact ISO 15552 interface, 50mm bore, 300mm stroke, G1/4 port, and FTC trunnion mount. Confirm your thread standard (PT/G/NPT) and magnet requirement. For sizing, a 40mm bore yields 628N push at 0.5MPa, while a 63mm bore yields 1559N. At 300mm stroke, use an external guide to prevent rod bending and side-load wear. A plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X300SFTC
- ✓ 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 SI50X300SFTC FAQ
Yes, the SI50X300SFTC is discontinued. The direct replacement is the SAI50X300SFTC. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 300mm stroke, G1/4 port, and FTC trunnion mount.
This double-acting cylinder uses a G1/4 air port. It generates 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical max of 200kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X300SFTC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X300SFTC replacement — usually within 7-8 hours.