This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X50LB, 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 SI50X50LB
The AirTAC SI50 Standard Cylinder SI50X50LB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 50mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X50LB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke50 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X50LB
- 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 SI50X50LB
The AirTAC SI50X50LB is a discontinued double-acting ISO 15552 profile cylinder with an LB foot mount. Built for a 50 mm bore and 50 mm stroke, it delivers 982 N push force at 0.5 MPa through a G1/4 port. The direct replacement is the SAI50X50LB, matching the exact interface, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure. This SKU lacks a magnet, so it cannot accept CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X50LB Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X50LB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X50LB |
| Bore size | Ø50 mm |
| Stroke | 50 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 SAI50X50LB 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 SAI50X50LB 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 SI50X50LB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×50 | 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 SI50X50LB Is Used
Package Diverting
Drives diverter arms on packaging lines where the 982 N push force easily redirects standard cartons.
Pallet Stop Gate
Actuates 50 mm stroke stop gates at pallet workstations using the LB foot mounting bracket.
Clamp Actuation
Secures medium workpieces during machining, providing 825 N pull force for reliable hold.
Replacing the Airtac SI50 Standard Cylinder SI50X50LB with the SAI50X50LB
To replace the SI50X50LB, order the SAI50X50LB. Verify the ISO 15552 LB foot mount, 50 mm stroke, G1/4 port, and M16x1.5 rod thread. Because this specific SKU has no -S magnet, it cannot support position sensing; order a magnet-equipped SAI if switches are needed. If more force is required, step up to the 63 mm bore (1559 N push at 0.5 MPa); if less is needed, the 40 mm bore offers 628 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates. For load holding, use an external pilot check valve, rod lock, or the SAIL/BSAI lock variants. The SAI family also adds the SAIF self-valve option.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X50LB
- ✓ 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 SI50X50LB FAQ
Yes, the SI50X50LB is discontinued. The direct replacement is the SAI50X50LB. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 50 mm stroke, LB foot mount, and G1/4 port.
The G1/4 port feeds a 50 mm bore that generates 982 N push and 825 N pull at 0.5 MPa. At 0.7 MPa push is 1374 N, and the theoretical maximum force is 200 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X50LB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X50LB replacement — usually within 7-8 hours.