This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX180S, 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 SI50BX180S
The AirTAC Airtac SI50 Standard Cylinder SI50BX180S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 180mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX180S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke180 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX180S
- 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 SI50BX180S
The AirTAC SI50BX180S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore, 180mm stroke, and a SUS304 stainless piston rod. Delivering 982N push force at 0.5MPa, it features a G1/4 air port and M16x1.5 rod thread. The direct replacement is the SAI50BX180S, matching the bore, stroke, force, port, and ISO 15552 mounting interface for existing fixtures.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life, while the SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked. This -S model includes a piston magnet for legacy CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50BX180S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX180S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX180S |
| Bore size | Ø50 mm |
| Stroke | 180 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 SAI50BX180S 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 SAI50BX180S 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 SI50BX180S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×180 | 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 SI50BX180S Is Used
Stainless Rod Diverter
Ideal for diverting packages on a washdown conveyor line, utilizing the 180mm stroke and SUS304 rod for corrosion resistance.
Compact Parts Ejector
Ejects machined components from a fixture using the 50mm bore's 825N pull force, fitting neatly into ISO 15552 tooling.
Replacing the Airtac SI50 Standard Cylinder SI50BX180S with the SAI50BX180S
To replace the SI50BX180S, order the SAI50BX180S. Verify your ISO 15552 mounting accessories (LB, FA, TC, etc.), the G1/4 port thread, and the M16x1.5 rod end. The -S magnet works with legacy CS1-B/DS1-B switches, though the SAI replacement uses current AirTAC sensors. The -B rod is SUS304 stainless steel for corrosion resistance. If sizing up or down, neighbouring bores are 40mm (628N push @0.5MPa) and 63mm (1559N push @0.5MPa). A plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX180S
- ✓ 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 SI50BX180S FAQ
Yes, the SI50BX180S is discontinued. The direct replacement is the SAI50BX180S. It is a true ISO 15552 profile cylinder that matches the 50mm bore, 180mm stroke, 982N force, G1/4 port, and mounting dimensions, fitting directly into existing fixtures.
The 50mm bore uses a G1/4 air port. At 0.5MPa it provides 982N push and 825N pull force. At 0.7MPa push is 1374N, and at 0.9MPa push is 1767N. The theoretical maximum force is 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX180S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX180S replacement — usually within 7-8 hours.