This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX45, 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 SI50BX45
The AirTAC Airtac SI50 Standard Cylinder SI50BX45 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 SAI50BX45, 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 → SAI50BX45
- 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 SI50BX45
The AirTAC SI50BX45 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 45mm stroke, delivering 982 N push force at 0.5 MPa. It features a Ø20 mm rod, M16x1.5 thread, and a G1/4 port. As an end-of-life product, it is replaced by the SAI50BX45 direct, which maintains the exact ISO 15552 mounting interface and output force.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. Note this SKU lacks a magnet (-S) and cannot accept CS1-B/DS1-B sensors. For high heat, Viton H seals raise limits to 150 C; the -B SUS304 rod resists corrosion.
Airtac SI50 Standard Cylinder SI50BX45 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX45 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX45 |
| 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 SAI50BX45 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 SAI50BX45 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 SI50BX45
| 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 SI50BX45 Is Used
Short-Stroke Clamping
Ideal for holding parts during machining, using its 982 N push force to secure workpieces firmly within a compact 45mm travel envelope.
Package Diverting
Provides rapid actuation at 30-800 mm/s for sorting or diverting light materials on packaging lines without needing position sensors.
Ejector Mechanisms
Delivers reliable ejection force for finished goods from fixtures, utilizing the 50mm bore's 825 N pull force at 0.5 MPa.
Replacing the Airtac SI50 Standard Cylinder SI50BX45 with the SAI50BX45
To replace the SI50BX45, order the SAI50BX45, confirming the ISO 15552 interface, 50mm bore, 45mm stroke, G1/4 port, and mounting accessory. Because this non-magnetic SKU lacks a sensor groove switch, you cannot install position sensing. If sizing alternatives, a 40mm bore yields 628 N push at 0.5 MPa, while a 63mm bore offers 1559 N. A plain cylinder drifts on air loss since cushions only decelerate; for load holding, specify the SAIL lock or BSAI clamp-lock variant, or use an external pilot check valve. The 45mm stroke avoids rod-bending side-load issues seen in longer travels.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX45
- ✓ 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 SI50BX45 FAQ
Yes, the SI50BX45 is discontinued. The direct replacement is the SAI50BX45. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 45mm stroke, G1/4 port, and mounting fixtures, but features an upgraded two Y-shaped piston seal for longer life.
This double-acting cylinder uses a G1/4 air port. It delivers 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and 1767 N push at 0.9 MPa. The theoretical maximum force is 200 kgf at 1.0 MPa, operating at 30-800 mm/s.
Request a Quote for the SAI50BX45
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX45 replacement — usually within 7-8 hours.