This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX120, 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 SI50BX120
The AirTAC Airtac SI50 Standard Cylinder SI50BX120 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 120mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX120, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke120 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX120
- 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 SI50BX120
The AirTAC SI50BX120 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 120mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50BX120, matching the interface, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU lacks a magnet and cannot take a sensor, unlike the CS1-B/DS1-B legacy switches used on -S models. The -B rod is SUS304 stainless steel.
Airtac SI50 Standard Cylinder SI50BX120 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX120 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX120 |
| Bore size | Ø50 mm |
| Stroke | 120 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 SAI50BX120 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 SAI50BX120 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 SI50BX120
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×120 | 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 SI50BX120 Is Used
Package Diverting
Provides the 982N push at 0.5MPa needed to actuate routing gates on 50kg payload conveyor lines without overshooting.
Stainless Forming
The SUS304 rod option excels in light metal-bending jigs where coolant spray would corrode standard carbon steel rods.
Vertical Lift Stops
Lifts approximately 50kg to a 120mm raised stop; pair with a pilot check valve to prevent drift if air pressure drops.
Replacing the Airtac SI50 Standard Cylinder SI50BX120 with the SAI50BX120
To replace the SI50BX120, order the SAI50BX120. Confirm the ISO 15552 mounting interface, 50mm bore, 120mm stroke, G1/4 port (PT/G/NPT thread), and your specific mounting accessory (LB, FA, TC, etc.). Because this SKU has no -S magnet, it cannot accept position sensors. Sizing both ways: a 40mm bore yields 628N push at 0.5MPa, while a 63mm bore yields 1559N. Note that a plain cylinder drifts on air loss—the cushion only decelerates. For load holding, use an external pilot check valve or the SAIL/BSAI lock variants. The SUS304 (-B) rod is ideal for corrosive settings.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX120
- ✓ 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 SI50BX120 FAQ
Yes, the SI50BX120 is discontinued. The direct replacement is the SAI50BX120. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 120mm stroke, G1/4 port, and mounting fixtures exactly.
The G1/4 port feeds a 50mm bore yielding 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N at 0.9MPa, and a 200kgf max at 1.0MPa. The rod is Ø20mm with an M16x1.5 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX120
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX120 replacement — usually within 7-8 hours.