This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X310S, 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 SI50X310S
The AirTAC Airtac SI50 Standard Cylinder SI50X310S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 310mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X310S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke310 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X310S
- 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 SI50X310S
The AirTAC SI50X310S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 310mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI50X310S, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke, and output force.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also introduces lock and valve variants the SI lacked, and you can specify Viton H seals for high-temperature duties.
Airtac SI50 Standard Cylinder SI50X310S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X310S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X310S |
| Bore size | Ø50 mm |
| Stroke | 310 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 SAI50X310S 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 SAI50X310S 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 SI50X310S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×310 | 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 SI50X310S Is Used
Package Diversion
Actuates routing gates on packaging lines, utilizing the 982N push force to deflect heavy cartons reliably at speed.
Vertical Material Lift
Raises and lowers light fixtures with a safe vertical lift capacity of roughly 50kg, ensuring smooth deceleration via adjustable cushions.
Press Ejection
Ejects machined parts from press beds, where the 310mm stroke provides the necessary reach to clear the tooling area.
Replacing the Airtac SI50 Standard Cylinder SI50X310S with the SAI50X310S
To replace the SI50X310S, order the SAI50X310S and confirm the ISO 15552 mounting interface, G1/4 port, M16x1.5 rod thread, and 310mm stroke. This unit includes a magnet for CS1-B/DS1-B switches, though the SAI replacement family uses current AirTAC sensors. If sizing up or down, neighboring bores are 40mm and 63mm, offering 628N and 1559N push force at 0.5MPa respectively. Because this is a 310mm stroke, use external guides to prevent rod bending and side-load damage. A plain cylinder does not hold load without live air; for load holding on air loss, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X310S
- ✓ 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 SI50X310S FAQ
Yes, the SI50X310S is discontinued. The direct replacement is the SAI50X310S. It shares the identical ISO 15552 mounting interface, 50mm bore, 310mm stroke, output force, and G1/4 port, fitting directly into existing fixtures.
This double-acting cylinder uses a G1/4 air port. The force output is 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical maximum of 200kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X310S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X310S replacement — usually within 7-8 hours.