This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X80STC, 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 SI50X80STC
The AirTAC Airtac SI50 Standard Cylinder SI50X80STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 80mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X80STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke80 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X80STC
- 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 SI50X80STC
The AirTAC SI50X80STC is a discontinued double-acting ISO 15552 profile cylinder with an 80 mm stroke and TC trunnion mount. Delivering 982 N push force at 0.5 MPa via a G1/4 port, it is replaced by the SAI50X80STC. This direct upgrade shares 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. It also adds SAIL, SAIF and BSAI variants the SI lacked. The -S magnet works with legacy CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X80STC Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X80STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X80STC |
| Bore size | Ø50 mm |
| Stroke | 80 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 SAI50X80STC 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 SAI50X80STC 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 SI50X80STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×80 | 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 SI50X80STC Is Used
Package Diversion
Drives a 50 kg routing gate on a packaging line, utilising the 80 mm stroke and 982 N push force to redirect boxes at high speed.
Clamp Actuation
Secures medium aluminium workpieces in a machining fixture, providing 825 N pull force at 0.5 MPa via the TC trunnion mount.
Pallet Stopper
Acts as a pneumatic stop for incoming pallets on a roller conveyor, absorbing impact with the 30 mm adjustable air cushion.
Replacing the Airtac SI50 Standard Cylinder SI50X80STC with the SAI50X80STC
To replace the SI50X80STC, order the SAI50X80STC. Confirm the ISO 15552 TC trunnion mount, 50 mm bore, 80 mm stroke, G1/4 port (PT/G/NPT thread options) and the -S magnet. It delivers 982 N push at 0.5 MPa; neighbouring bores are 40 mm (628 N) and 63 mm (1559 N). A plain cylinder drifts on air loss as the cushion only decelerates; for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. The SAI family also offers the SAIF self-valve variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X80STC
- ✓ 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 SI50X80STC FAQ
Yes, the SI50X80STC is discontinued. The direct replacement is the SAI50X80STC. It shares the same ISO 15552 TC mounting interface, 50 mm bore, 80 mm stroke, G1/4 port and output force, fitting existing fixtures perfectly.
This double-acting cylinder has a G1/4 air port. The force ratings are 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X80STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X80STC replacement — usually within 7-8 hours.