This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X490, 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 SI50X490
The AirTAC Airtac SI50 Standard Cylinder SI50X490 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 490mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X490, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke490 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X490
- 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 SI50X490
The AirTAC SI50X490 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 490mm stroke, delivering 982N push force at 0.5 MPa. It is directly replaced by the SAI50X490. This direct successor shares the exact same interface, G1/4 port, and output, fitting existing fixtures perfectly.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. Note this SKU lacks a magnet, so it cannot take a sensor. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI50 Standard Cylinder SI50X490 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X490 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X490 |
| Bore size | Ø50 mm |
| Stroke | 490 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 SAI50X490 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 SAI50X490 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 SI50X490
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×490 | 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 SI50X490 Is Used
Long-Stroke Diverting
Handles 490mm package routing on conveyor lines where the 982N push force at 0.5 MPa easily overcomes sliding friction.
Multi-Stage Ejection
Pushes completed parts out of machining centers using the 1767N thrust available at 0.9 MPa over the extended stroke.
Replacing the Airtac SI50 Standard Cylinder SI50X490 with the SAI50X490
To replace the SI50X490, order the SAI50X490, confirming the ISO 15552 mounting interface, 50mm bore, 490mm stroke, G1/4 port, and M16x1.5 rod thread. This non-magnet SKU cannot accept a CS1-B/DS1-B sensor. If sizing up or down, note the 40mm bore yields 628N push at 0.5 MPa, while the 63mm bore yields 1559N. Because the 490mm stroke is long, use an external guide to prevent rod bending and side-load wear. The air cushion only decelerates; it does not hold load 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 → SAI50X490
- ✓ 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 SI50X490 FAQ
Yes, the SI50X490 is discontinued. The direct replacement is the SAI50X490. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 490mm stroke, output force, G1/4 port, and mounting accessories.
The G1/4 port is fixed by the 50mm bore. It delivers 982N push and 825N pull at 0.5 MPa, 1374N push at 0.7 MPa, 1767N push at 0.9 MPa, and a theoretical max of 200 kgf at 1.0 MPa. Speed is 30-800 mm/s.
Request a Quote for the SAI50X490
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X490 replacement — usually within 7-8 hours.