This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX450S, 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 SI50BX450S
The AirTAC Airtac SI50 Standard Cylinder SI50BX450S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 450mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX450S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke450 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX450S
- 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 SI50BX450S
The AirTAC SI50BX450S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 450mm stroke. Delivering 982 N push and 825 N pull at 0.5 MPa through a G1/4 port, its direct replacement is the SAI50BX450S. The SAI upgrade shares identical mounting, force, and stroke specs, but introduces an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life.
This -S variant includes a piston magnet for legacy CS1-B/DS1-B sensors, while the -B code specifies a SUS304 stainless steel rod for corrosion resistance. The SAI family also adds SAIL, SAIF, and BSAI lock or valve variants the original SI lacked.
Airtac SI50 Standard Cylinder SI50BX450S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX450S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX450S |
| Bore size | Ø50 mm |
| Stroke | 450 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 SAI50BX450S 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 SAI50BX450S 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 SI50BX450S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×450 | 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 SI50BX450S Is Used
Material Diverting
Actuates diverter arms on packaging lines, utilizing the 50mm bore's 982 N thrust to push cartons reliably at cycling speeds.
Vertical Lift Gates
Raises lightweight access gates or barriers; the SUS304 rod provides corrosion resistance in humid or wash-down warehouse environments.
Press Fit Depalletizing
Drives 450mm stroke lowering motions to engage and lift layered products, requiring external guides to manage the long rod extension.
Replacing the Airtac SI50 Standard Cylinder SI50BX450S with the SAI50BX450S
To replace the SI50BX450S, order the SAI50BX450S: it matches the ISO 15552 mounting interface, 50mm bore, 450mm stroke, G1/4 port, and M16x1.5 rod thread. Retain your existing mounting accessories and confirm the -S magnet for current AirTAC switch compatibility. For sizing alternatives, a 40mm bore yields 628 N push at 0.5 MPa, while a 63mm bore offers 1559 N. Note that a plain cylinder drifts on air loss as the cushion only decelerates; for load holding, specify the SAIL lock, BSAI clamp-lock, or an external pilot check valve. At 450mm, prevent rod bending by guiding the load externally to avoid side-loading.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX450S
- ✓ 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 SI50BX450S FAQ
Yes, the SI50BX450S is discontinued. The direct replacement is the SAI50BX450S. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 450mm stroke, 982 N force, G1/4 port, and mounting fixtures.
This double-acting cylinder uses a G1/4 port. Theoretical forces are: 982 N push and 825 N pull at 0.5 MPa; 1374 N push at 0.7 MPa; 1767 N push at 0.9 MPa; and a maximum force of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX450S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX450S replacement — usually within 7-8 hours.