This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X370S, 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 SI50X370S
The AirTAC Airtac SI50 Standard Cylinder SI50X370S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 370mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X370S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke370 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X370S
- 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 SI50X370S
The AirTAC SI50X370S is a discontinued double-acting ISO 15552 profile cylinder featuring a 50mm bore, 370mm stroke, and a G1/4 air port. Delivering 982 N of push force at 0.5 MPa, it is replaced by the SAI50X370S. This direct successor shares identical mounting interface, bore, stroke, and port dimensions, fitting existing fixtures perfectly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The -S suffix means this SI includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL lock, SAIF valve, and BSAI clamp-lock variants the original SI lacked.
Airtac SI50 Standard Cylinder SI50X370S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X370S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X370S |
| Bore size | Ø50 mm |
| Stroke | 370 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 SAI50X370S 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 SAI50X370S 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 SI50X370S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×370 | 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 SI50X370S Is Used
Material Diversion
Drives diverter gates on packaging lines using the 982 N push force at 0.5 MPa to redirect cartons reliably.
Pallet Handling
Actuates stoppers and lifts in pallet flow systems where the G1/4 port and ISO 15552 mounts integrate easily.
Replacing the Airtac SI50 Standard Cylinder SI50X370S with the SAI50X370S
To replace the SI50X370S, order the SAI50X370S and verify the ISO 15552 mounting interface, G1/4 port thread (PT/G/NPT), and your specific mounting accessory (LB, FA, TC, etc.). The -S magnet is present for position sensing. If you need to size up or down, neighbouring bores are 40mm (628 N [email protected]) and 63mm (1559 N [email protected]). Because this is a 370mm stroke, use an external guide to prevent rod bending and side-load damage. A plain SAI does not hold load without live air; the cushion only decelerates. For load holding, use an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X370S
- ✓ 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 SI50X370S FAQ
Yes, the AirTAC SI50X370S is discontinued. The direct replacement is the SAI50X370S. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 370mm stroke, G1/4 port, and mounting interface.
This double-acting cylinder features a G1/4 air port and provides 982 N push and 825 N pull at 0.5 MPa. It delivers 1374 N push at 0.7 MPa and 1767 N at 0.9 MPa, with a theoretical max force of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X370S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X370S replacement — usually within 7-8 hours.