This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X175STC, 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 SI50X175STC
The AirTAC Airtac SI50 Standard Cylinder SI50X175STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 175mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X175STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke175 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X175STC
- 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 SI50X175STC
The AirTAC SI50X175STC is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 175mm stroke. It delivers 982N push and 825N pull at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI50X175STC, a direct upgrade sharing the exact ISO 15552 mounting interface, TC trunnion mount, and force class.
The SAI replacement features an upgraded piston seal using two Y-shaped one-way elements for low start-up pressure and long life. The SAI family also introduces SAIL, SAIF, and BSAI lock variants absent in the SI line. Your -S code denotes a piston magnet for legacy CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X175STC Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X175STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X175STC |
| Bore size | Ø50 mm |
| Stroke | 175 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 SAI50X175STC 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 SAI50X175STC 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 SI50X175STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×175 | 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 SI50X175STC Is Used
Package Diversion
Routes medium-weight cartons on packaging lines using the 982N push force and 175mm stroke to actuate routing gates.
Pallet Stops
Controls pallet flow on accumulation conveyors, using the TC trunnion mount to accommodate angular misalignment.
Replacing the Airtac SI50 Standard Cylinder SI50X175STC with the SAI50X175STC
To replace this SI50X175STC, order the SAI50X175STC. Confirm the ISO 15552 TC trunnion interface, 50mm bore, 175mm stroke, G1/4 port, and the -S magnet. If you need more force, the neighbouring 63mm bore yields 1559N push at 0.5MPa; if less is required, the 40mm bore offers 628N. A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding use an external pilot check valve or the SAIL/BSAI lock variants. At 175mm stroke, side-load risks are low, but ensure the TC trunnion pivots freely to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X175STC
- ✓ 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 SI50X175STC FAQ
Yes, the SI50X175STC is discontinued. The direct replacement is the SAI50X175STC. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 175mm stroke, G1/4 port, TC mounting, and output force.
This 50mm bore cylinder uses a G1/4 air port. It generates 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, and a theoretical maximum force of 200kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X175STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X175STC replacement — usually within 7-8 hours.