This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX500, 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 SI50BX500
The AirTAC Airtac SI50 Standard Cylinder SI50BX500 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 500mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX500, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke500 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX500
- 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 SI50BX500
The AirTAC SI50BX500 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 500 mm stroke. It delivers 982 N push force at 0.5 MPa through a G1/4 port. The direct replacement is the SAI50BX500, which preserves the exact ISO 15552 mounting interface, bore, stroke, output force, and port size for existing fixtures. This specific SKU features a SUS304 stainless steel rod (-B) but lacks a magnet, meaning it cannot accept position sensors.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. Note that a plain cylinder drifts on air loss; the air cushion only decelerates the piston near stroke end. For load holding, consider an external pilot check valve or the SAIL/BSAI lock variants.
Airtac SI50 Standard Cylinder SI50BX500 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX500 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX500 |
| Bore size | Ø50 mm |
| Stroke | 500 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 SAI50BX500 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 SAI50BX500 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 SI50BX500
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×500 | 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 SI50BX500 Is Used
Long-Stroke Diversion
Pushes packages across transfer lines using the 500 mm stroke, relying on the 982 N force at 0.5 MPa to overcome friction.
Corrosive Environment Actuation
Drives mechanisms in washdown or chemical zones using the SUS304 stainless steel rod option for corrosion resistance.
Replacing the Airtac SI50 Standard Cylinder SI50BX500 with the SAI50BX500
To replace the SI50BX500, order the SAI50BX500. Confirm the ISO 15552 mounting interface, the 50 mm bore, the 500 mm stroke, the G1/4 port (PT/G/NPT), and your mounting accessory. Because this SKU has no -S magnet, it cannot support legacy CS1-B/DS1-B switches; order a magnet-equipped SAI if sensing is needed. When sizing, a 40 mm bore yields 628 N push at 0.5 MPa, while a 63 mm bore yields 1559 N. At 500 mm stroke, prevent rod bending by guiding the load externally to avoid side-load forces. For load holding on air loss, use an external rod lock or pilot check valve, or specify the SAIL or BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX500
- ✓ 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 SI50BX500 FAQ
Yes, the SI50BX500 is discontinued. The direct replacement is the SAI50BX500. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 500 mm stroke, 982 N force, and G1/4 port.
At 0.5 MPa it provides 982 N push and 825 N pull. At 0.7 MPa push is 1374 N, and at 0.9 MPa it is 1767 N. The theoretical max force is 200 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX500
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX500 replacement — usually within 7-8 hours.