This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X150SFA, 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 SI50X150SFA
The AirTAC Airtac SI50 Standard Cylinder SI50X150SFA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 150mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X150SFA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke150 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X150SFA
- 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 SI50X150SFA
The AirTAC SI50X150SFA is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore, 150 mm stroke, FA flange mounting, and a magnetic piston. Delivering 982 N push force at 0.5 MPa, it features a 20 mm carbon steel rod, M16x1.5 thread, and a G1/4 port. The direct replacement is the SAI50X150SFA, which preserves the original ISO 15552 mounting interface, output force, and stroke.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. For applications needing load holding on air loss, the SAI family adds the SAIL lock and BSAI clamp-lock variants the SI lacked. The -S magnet supports legacy CS1-B/DS1-B sensors, while a Viton H seal raises operating temperature to 150 C.
Airtac SI50 Standard Cylinder SI50X150SFA Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X150SFA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X150SFA |
| Bore size | Ø50 mm |
| Stroke | 150 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 SAI50X150SFA 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 SAI50X150SFA 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 SI50X150SFA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×150 | 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 SI50X150SFA Is Used
Clamp Actuation
Provides 982 N of clamping thrust at 0.5 MPa for securing mid-weight machining fixtures.
Package Diverting
Drives a 150 mm stroke diverter arm to route moderate loads along material handling lines.
Replacing the Airtac SI50 Standard Cylinder SI50X150SFA with the SAI50X150SFA
To replace the SI50X150SFA, order the SAI50X150SFA. It is a direct: the ISO 15552 FA flange interface, 50 mm bore, 150 mm stroke, G1/4 port, and M16x1.5 rod thread remain identical. Retain the -S magnet option for current AirTAC switches (replacing legacy CS1-B/DS1-B units). If sizing up or down, neighbouring bores are 40 mm (628 N push @0.5 MPa) and 63 mm (1559 N push @0.5 MPa). A plain cylinder drifts on air loss; the air cushion only decelerates near stroke end. For held loads, specify the SAIL or BSAI lock variant, or use an external pilot check valve. At 150 mm stroke, side-load is minimal, but ensure front flange alignment to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X150SFA
- ✓ 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 SI50X150SFA FAQ
Yes, the SI50X150SFA is discontinued. The direct replacement is the SAI50X150SFA. It shares the identical ISO 15552 FA flange mounting interface, 50 mm bore, 150 mm stroke, G1/4 port, and output force, fitting existing fixtures without modification.
The G1/4 port supplies a 20 mm rod. At 0.5 MPa it yields 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 SAI50X150SFA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X150SFA replacement — usually within 7-8 hours.