This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X450STC, 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 SI50X450STC
The AirTAC Airtac SI50 Standard Cylinder SI50X450STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 450mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X450STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke450 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X450STC
- 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 SI50X450STC
The AirTAC SI50X450STC is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 450mm stroke. It delivers 982 N push force at 0.5 MPa via a G1/4 port. The direct replacement is the SAI50X450STC, matching the exact bore, stroke, force, and TC trunnion mounting interface.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. It adds variants the SI lacked, like the SAIL lock and SAIF valve. The -S magnet works with CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X450STC Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X450STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X450STC |
| Bore size | Ø50 mm |
| Stroke | 450 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 SAI50X450STC 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 SAI50X450STC 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 SI50X450STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×450 | 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 SI50X450STC Is Used
TC Trunnion Assembly
Pivots within a fixture using the ISO 15552 TC mount, absorbing alignment shifts during the 450mm extension cycle.
Replacing the Airtac SI50 Standard Cylinder SI50X450STC with the SAI50X450STC
To replace the SI50X450STC, order the SAI50X450STC. Confirm the ISO 15552 TC trunnion mount, 50mm bore, 450mm stroke, G1/4 port, and the -S magnet for CS1-B/DS1-B switches. For sizing, a 40mm bore gives 628 N push at 0.5 MPa, while a 63mm bore yields 1559 N. A 450mm stroke requires external guides to prevent rod bending under side loads. A plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X450STC
- ✓ 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 SI50X450STC FAQ
Yes, the SI50X450STC is discontinued. The direct replacement is the SAI50X450STC, offering the same ISO 15552 TC trunnion mount, 50mm bore, 450mm stroke, force, and G1/4 port.
The G1/4 port feeds a 50mm bore yielding 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a 200 kgf max at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X450STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X450STC replacement — usually within 7-8 hours.