This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X630S, 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 SI50X630S
The AirTAC SI50 Standard Cylinder SI50X630S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 630mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X630S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke630 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X630S
- 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 SI50X630S
The AirTAC SI50X630S is a discontinued double-acting ISO 15552 profile cylinder featuring a 50mm bore, 630mm stroke, and a built-in magnet for CS1-B/DS1-B switches. Delivering 982 N push force at 0.5 MPa, it is directly replaced by the SAI50X630S. This direct upgrade shares the exact ISO 15552 mounting interface, G1/4 port, and M16x1.5 rod thread, fitting existing fixtures perfectly.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. If you need load holding on air loss, the SAI lacks a native lock, but the SAIL or BSAI clamp-lock variants can help.
Airtac SI50 Standard Cylinder SI50X630S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X630S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X630S |
| Bore size | Ø50 mm |
| Stroke | 630 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 SAI50X630S 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 SAI50X630S 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 SI50X630S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×630 | 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 SI50X630S Is Used
Long-Stroke Diversion
Pushes packages across transfer lines using the full 630mm extension, relying on external guides to prevent rod bending.
Vertical Material Lift
Raises goods up to 50 kg in storage racks, requiring a pilot-operated check valve to prevent drifting on air loss.
Multi-Station Indexing
Shifts tooling pallets between machining cells, using the built-in magnet and CS1-B sensors to confirm end positions.
Replacing the Airtac SI50 Standard Cylinder SI50X630S with the SAI50X630S
To replace the SI50X630S, order the SAI50X630S. Confirm the ISO 15552 mounting accessory (LB, FA, TC, etc.), the G1/4 port, and the magnet requirement. The SAI family adds SAIF (built-in valve) and SAIL (air-released lock) options the SI lacked. A plain cylinder drifts on air loss; cushions only decelerate, so use an external rod lock or pilot check valve for holding. With a 630mm stroke, prevent rod bending by guiding the load externally to avoid side-load damage. Sizing both ways: if you need more force, the 63mm bore offers 1559 N push at 0.5 MPa; if less, the 40mm bore provides 628 N.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X630S
- ✓ 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 SI50X630S FAQ
Yes, the SI50X630S is discontinued. The direct replacement is the SAI50X630S. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 630mm stroke, G1/4 port, and mounting interface.
It features a G1/4 air port. The force ratings are: 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. The rod is 20mm with an M16x1.5 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X630S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X630S replacement — usually within 7-8 hours.