This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X1370S, 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 SI50X1370S
The AirTAC SI50 Standard Cylinder SI50X1370S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 1370mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X1370S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke1370 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X1370S
- 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 SI50X1370S
The AirTAC SI50X1370S is a discontinued double-acting ISO 15552 profile cylinder with an extruded aluminum barrel. It delivers 982 N push force at 0.5 MPa through a 50 mm bore, uses a G1/4 port, and features a built-in magnet for CS1-B/DS1-B sensors. Because its 1370 mm stroke exceeds the 1200 mm standard maximum, it is a made-to-order non-standard item requiring external guidance to prevent rod bending.
AirTAC replaced this unit with the SAI50X1370S, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke, force, and port. The SAI features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life.
Airtac SI50 Standard Cylinder SI50X1370S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X1370S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X1370S |
| Bore size | Ø50 mm |
| Stroke | 1370 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 SAI50X1370S 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 SAI50X1370S 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 SI50X1370S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×1370 | 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 SI50X1370S Is Used
Long-Stroke Diversion
Pushes packages across transfer lines over a 1370 mm span, requiring external guides to prevent rod bending during lateral actuation.
Vertical Material Lift
Raises light fixtures or bins up to 50 kg using the 982 N push force at 0.5 MPa, paired with a pilot check valve to hold the load safely.
Elevated Tooling Stage
Actuates upper tooling platforms in assembly machinery, utilizing the adjustable 30 mm air cushions at both ends to decelerate the long travel.
Replacing the Airtac SI50 Standard Cylinder SI50X1370S with the SAI50X1370S
To replace this SI50X1370S, order the SAI50X1370S direct equivalent, confirming the ISO 15552 interface, 50 mm bore, 1370 mm non-standard stroke, G1/4 port, and the -S magnet for legacy CS1-B/DS1-B switches (the SAI uses current AirTAC switches). Size both ways: step up to a 63 mm bore for more force, or down to a 40 mm bore if 628 N push at 0.5 MPa is sufficient. Note that a plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock or pilot check valve for load holding, or specify the SAIL or BSAI lock variant. At 1370 mm, add external guides to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X1370S
- ✓ 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 SI50X1370S FAQ
Yes, the SI50X1370S is discontinued. The direct replacement is the AirTAC SAI50X1370S. It shares the same ISO 15552 mounting interface, 50 mm bore, 1370 mm stroke, output force, and G1/4 port, fitting existing fixtures directly while adding an upgraded piston seal.
This 50 mm bore cylinder uses a G1/4 air port and provides 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, 1767 N push at 0.9 MPa, and a theoretical maximum of 200 kgf at 1.0 MPa. The 1370 mm stroke is non-standard (exceeding the 1200 mm max standard) and operates at 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X1370S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X1370S replacement — usually within 7-8 hours.