This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX45S, 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 SI50BX45S
The AirTAC Airtac SI50 Standard Cylinder SI50BX45S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 45mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX45S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke45 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX45S
- 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 SI50BX45S
The AirTAC SI50BX45S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 45 mm stroke. It delivers 982 N push and 825 N pull at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50BX45S, a direct replacement sharing the exact ISO 15552 mounting interface, bore, stroke, force, port and mounting accessories. The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Furthermore, the SAI family introduces SAIL, SAIF and BSAI lock variants absent from the SI line.
This specific SKU includes a -B SUS304 stainless piston rod for corrosion resistance and an -S magnet for legacy CS1-B/DS1-B switches. For elevated thermal demands, a Viton H seal option expands the operating range to 0-150 C.
Airtac SI50 Standard Cylinder SI50BX45S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX45S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX45S |
| Bore size | Ø50 mm |
| Stroke | 45 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 SAI50BX45S 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 SAI50BX45S 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 SI50BX45S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×45 | 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 SI50BX45S Is Used
Corrosive Clamping
Ideal for fixture clamping in washdown or chemical environments utilizing the SUS304 stainless rod to prevent corrosion.
Package Diverting
Short 45 mm stroke provides rapid actuation for routing lightweight packages on sorting lines at speeds up to 800 mm/s.
Replacing the Airtac SI50 Standard Cylinder SI50BX45S with the SAI50BX45S
To replace the discontinued SI50BX45S, order the SAI50BX45S. Confirm the ISO 15552 mounting interface, 50 mm bore, 45 mm stroke, G1/4 port (PT/G/NPT thread), and mounting accessory match your fixture. Retain the -S magnet requirement for current AirTAC switches and the -B SUS304 rod for corrosion resistance. When sizing, consider the neighboring 40 mm bore (628 N push @0.5 MPa) for lighter loads or the 63 mm bore (1559 N push @0.5 MPa) for heavier demands. A plain cylinder does not hold load on air loss; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX45S
- ✓ 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 SI50BX45S FAQ
Yes, the AirTAC SI50BX45S is discontinued. The direct replacement is the SAI50BX45S. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 45 mm stroke, G1/4 port, and mounting interface for a seamless fixture upgrade.
This double-acting cylinder features a G1/4 port and delivers 982 N push and 825 N pull at 0.5 MPa. At 0.7 MPa push is 1374 N, and at 0.9 MPa it is 1767 N. The theoretical maximum force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX45S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX45S replacement — usually within 7-8 hours.