This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X440S, 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 SI50X440S
The AirTAC Airtac SI50 Standard Cylinder SI50X440S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 440mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X440S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke440 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X440S
- 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 SI50X440S
The AirTAC SI50X440S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 440 mm stroke. It delivers 982 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50X440S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, output force and port size.
The SAI upgrade features a modernized piston seal using two Y-shaped one-way elements for low start-up pressure and extended life. Because this is a -S model, it includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI replacement family uses current AirTAC switches.
Airtac SI50 Standard Cylinder SI50X440S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X440S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X440S |
| Bore size | Ø50 mm |
| Stroke | 440 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 SAI50X440S 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 SAI50X440S 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 SI50X440S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×440 | 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 SI50X440S Is Used
Package Diversion
Drives sorting arms on packaging lines where the 982 N push force at 0.5 MPa easily redirects standard totes.
Material Ejection
Ejects machined parts from fixtures, relying on the adjustable 30 mm air cushions to decelerate the rod smoothly.
Replacing the Airtac SI50 Standard Cylinder SI50X440S with the SAI50X440S
To replace the SI50X440S, order the SAI50X440S. Verify your ISO 15552 mounting accessory (LB foot, FA flange, TC trunnion), the G1/4 port thread (PT/G/NPT), and the M16x1.5 rod-end connection. The -S magnet equates to legacy CS1-B/DS1-B switches; the SAI family accepts current AirTAC sensors. For sizing alternatives, the neighboring 40 mm bore yields 628 N push at 0.5 MPa, while the 63 mm bore provides 1559 N. Note that a plain double-acting cylinder drifts on air loss—the cushion only decelerates near stroke end—so specify the SAIL or BSAI lock variant, or an external pilot check valve, if you need load holding. Finally, at 440 mm, this long stroke demands external guides to prevent rod bending under side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X440S
- ✓ 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 SI50X440S FAQ
Yes, the AirTAC SI50X440S is discontinued. The direct replacement is the SAI50X440S. It shares the identical ISO 15552 mounting interface, 50 mm bore, 440 mm stroke, output force, G1/4 port and mounting accessories, fitting directly into existing fixtures.
This double-acting cylinder has a G1/4 air port. It delivers 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a theoretical maximum of 200 kgf at 1.0 MPa. Operating pressure is 0.15-1.0 MPa, with a speed range of 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X440S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X440S replacement — usually within 7-8 hours.