This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X375S, 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 SI50X375S
The AirTAC Airtac SI50 Standard Cylinder SI50X375S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 375mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X375S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke375 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X375S
- 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 SI50X375S
The AirTAC SI50X375S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 375 mm stroke. Delivering 982 N push force at 0.5 MPa via a G1/4 port, it is replaced by the SAI50X375S. This direct upgrade shares identical ISO 15552 mounting dimensions, bore, stroke, output force, and porting. The SAI features an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life.
Because this is a -S model, it includes a piston magnet for legacy CS1-B/DS1-B sensors (the SAI replacement uses current AirTAC switches). The SI family lacked integrated lock options, but the SAI line adds SAIL (air-released lock), SAIF (built-in valve), and BSAI (clamp-lock) variants. Note that a plain cylinder drifts on air loss; the air cushion only decelerates near stroke ends. For high-temperature environments up to 150 C, a Viton H seal option is available.
Airtac SI50 Standard Cylinder SI50X375S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X375S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X375S |
| Bore size | Ø50 mm |
| Stroke | 375 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 SAI50X375S 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 SAI50X375S 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 SI50X375S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×375 | 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 SI50X375S Is Used
Package Diverting
Provides 982 N of push force to actuate diverters and sorting gates on medium-duty conveyor lines.
Pallet Handling
Drives 375 mm stroke gating and positioning stops at pallet transfer stations using ISO 15552 mounts.
Replacing the Airtac SI50 Standard Cylinder SI50X375S with the SAI50X375S
To replace the discontinued SI50X375S, order the SAI50X375S direct equivalent. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), the G1/4 port thread (PT/G/NPT), and the M16x1.5 rod-end connection. The -S suffix means a magnet is present for position sensing. If sizing up or down, adjacent bores are 40 mm (628 N push @0.5 MPa) and 63 mm (1559 N push @0.5 MPa). A standard cylinder does not hold load without live air; for holding, use an external pilot check valve or the SAIL/BSAI lock variant. At 375 mm stroke, prevent rod bending by guiding the load externally to avoid side-loading.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X375S
- ✓ 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 SI50X375S FAQ
Yes, the AirTAC SI50X375S is discontinued. The direct replacement is the SAI50X375S. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 375 mm stroke, output force, G1/4 port, and mounting interface.
The G1/4 port feeds a 50 mm bore yielding 982 N push and 825 N pull at 0.5 MPa. At 0.7 MPa push is 1374 N, and the theoretical max is 200 kgf at 1.0 MPa. The cushion is adjustable at both ends, and speed ranges 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X375S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X375S replacement — usually within 7-8 hours.