This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X50SFA, 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 SI50X50SFA
The AirTAC Airtac SI50 Standard Cylinder SI50X50SFA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 50mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X50SFA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke50 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X50SFA
- 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 SI50X50SFA
The AirTAC SI50X50SFA is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore, 50 mm stroke, FA flange mount, and a piston magnet. Built to deliver 982 N of push force at 0.5 MPa through a G1/4 port, it is directly replaced by the current-production SAI50X50SFA. This direct successor shares the exact ISO 15552 mounting interface, M16x1.5 rod thread, and 30 mm cushions, ensuring a seamless fixture swap.
The SAI upgrade introduces a refined piston seal featuring two Y-shaped one-way elements for lower start-up pressure and extended life. Note that a standard cylinder drifts without live air; for load holding, explore the SAIL or BSAI lock variants.
Airtac SI50 Standard Cylinder SI50X50SFA Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X50SFA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X50SFA |
| Bore size | Ø50 mm |
| Stroke | 50 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 SAI50X50SFA 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 SAI50X50SFA 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 SI50X50SFA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | 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 SI50 Standard Cylinder SI50X50SFA Is Used
Clamping Fixtures
Applies 982 N of push force at 0.5 MPa to secure medium-density workpieces during machining operations.
Package Diverting
Short 50 mm stroke actuates routing gates on packaging lines to redirect boxes efficiently.
Replacing the Airtac SI50 Standard Cylinder SI50X50SFA with the SAI50X50SFA
To replace the SI50X50SFA, order the SAI50X50SFA and verify your ISO 15552 FA flange mounting, 50 mm stroke, G1/4 port, and the -S magnet for legacy CS1-B/DS1-B sensors. If you need more force, the neighbouring 63 mm bore yields 1559 N at 0.5 MPa; if less is required, the 40 mm bore provides 628 N. Because this is a double-acting cylinder, it will not hold a load if air pressure drops—the cushion only decelerates near stroke end. For secure load holding, consider an external pilot check valve or the SAIL/BSAI lock variants. The SAI family also offers the SAIF self-valve option (bores 32-100) if integrated flow control is desired.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X50SFA
- ✓ 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 SI50X50SFA FAQ
Yes, the SI50X50SFA is discontinued. The direct replacement is the AirTAC SAI50X50SFA. It shares the identical ISO 15552 mounting interface, 50 mm bore, 50 mm stroke, G1/4 port, and FA flange, fitting directly into existing fixtures.
This 50 mm bore cylinder features a G1/4 air port and delivers a push force of 982 N and pull force of 825 N at 0.5 MPa. At 0.7 MPa it pushes 1374 N, and the theoretical maximum force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X50SFA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X50SFA replacement — usually within 7-8 hours.