This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX450S, 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 SI50AX450S
The AirTAC Airtac SI50 Standard Cylinder SI50AX450S 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 SAI50AX450S, 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 → SAI50AX450S
- 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 SI50AX450S
The AirTAC SI50AX450S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 450mm stroke. It features a SUS420J2 stainless piston rod and delivers 982 N push force at 0.5 MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI50AX450S, a direct replacement sharing the exact ISO 15552 mounting interface, bore, stroke, and output force.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The original SI-SKU includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI50 Standard Cylinder SI50AX450S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX450S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX450S |
| 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 SAI50AX450S 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 SAI50AX450S 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 SI50AX450S
| 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 SI50AX450S Is Used
Long-Stroke Diversion
Executes 450mm package routing on conveyor lines, using the 982 N push force to deflect heavy goods smoothly into sorting lanes.
Stainless Rod Actuation
Drives dampers and mechanisms in humid or mildly corrosive environments using the SUS420J2 stainless steel piston rod option.
Replacing the Airtac SI50 Standard Cylinder SI50AX450S with the SAI50AX450S
To replace this SI50AX450S, order the SAI50AX450S keeping the exact 50mm bore, 450mm stroke, G1/4 port, and ISO 15552 mounting. Retain the -S magnet for position sensing and the -A SUS420J2 stainless rod for corrosion resistance. If you need more force, the neighbouring 63mm bore yields 1559 N push at 0.5 MPa; if less is required, the 40mm bore gives 628 N. Note that a plain cylinder drifts on air loss as the cushion only decelerates, so use an external rod lock or pilot check valve for load holding, or specify an SAIL/BSAI lock variant. Because the 450mm stroke is long, add external guides to prevent rod bending and side-load damage.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX450S
- ✓ 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 SI50AX450S FAQ
Yes, the AirTAC SI50AX450S is discontinued. The direct replacement is the SAI50AX450S. It shares the identical ISO 15552 mounting interface, 50mm bore, 450mm stroke, output force, and G1/4 port, fitting directly into existing fixtures.
This 50mm bore cylinder uses a G1/4 air port. The thrust 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 SAI50AX450S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX450S replacement — usually within 7-8 hours.