This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX450, 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 SI50AX450
The AirTAC Airtac SI50 Standard Cylinder SI50AX450 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 SAI50AX450, 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 → SAI50AX450
- 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 SI50AX450
The AirTAC SI50AX450 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 450 mm stroke. It delivers 982 N push force at 0.5 MPa through a G1/4 port. The direct replacement is the SAI50AX450, matching the exact bore, stroke, force, port, and ISO 15552 mounting interface for seamless fixture integration.
This SKU features a SUS420J2 stainless steel rod but lacks a magnet, meaning it cannot accept a position switch. The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure. For high heat, Viton H seals raise the temperature limit to 150 C.
Airtac SI50 Standard Cylinder SI50AX450 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX450 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX450 |
| 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 SAI50AX450 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 SAI50AX450 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 SI50AX450
| 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 SI50AX450 Is Used
Elevated Lowering
Lowers 50 kg materials using the SUS420J2 stainless rod, requiring an external pilot check valve since cushions only decelerate.
Heat Treatment Handling
Operates near 150 C ovens using the Viton H seal option, moving parts smoothly at 30-800 mm/s within ISO 15552 fixtures.
Replacing the Airtac SI50 Standard Cylinder SI50AX450 with the SAI50AX450
To replace the SI50AX450, order the SAI50AX450 and verify your ISO 15552 mounting interface, G1/4 port, and M16x1.5 rod thread. Because this SKU has no magnet, you cannot mount switches; if sensing is needed, switch to an SAI50X450S. If less force is needed, a 40 mm bore provides 628 N; for more power, a 63 mm bore offers 1559 N. At 450 mm, the stroke is within the 1200 mm standard max, but add external guides to prevent rod bending and side-load damage. Note that air cushions only decelerate; they do not hold load on air loss, so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for secure holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX450
- ✓ 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 SI50AX450 FAQ
Yes, the SI50AX450 is discontinued. The direct replacement is the SAI50AX450. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 450 mm stroke, 982 N force, G1/4 port, and mounting interface.
The G1/4 port feeds a 50 mm bore yielding 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and 1767 N push at 0.9 MPa. The theoretical max force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX450
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX450 replacement — usually within 7-8 hours.