This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX115S, 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 SI50BX115S
The AirTAC Airtac SI50 Standard Cylinder SI50BX115S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 115mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX115S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke115 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX115S
- 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 SI50BX115S
The AirTAC SI50BX115S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore, 115mm stroke, and a SUS304 stainless steel rod. Delivering 982N push force at 0.5MPa, it is directly replaced by the SAI50BX115S. This direct upgrade retains the identical ISO 15552 mounting interface, G1/4 port, and 30mm adjustable cushions.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The original -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI50 Standard Cylinder SI50BX115S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX115S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX115S |
| Bore size | Ø50 mm |
| Stroke | 115 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 SAI50BX115S 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 SAI50BX115S 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 SI50BX115S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×115 | 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 SI50BX115S Is Used
Stainless Rod Diverters
Ideal for diverting packages on food-grade or washdown conveyor lines where the SUS304 rod resists corrosion and the 982N force handles side transfers.
Pneumatic Clamping Arms
Drives mid-force clamping arms in machining fixtures, using the 115mm stroke to clear the workpiece before loading the next part.
Replacing the Airtac SI50 Standard Cylinder SI50BX115S with the SAI50BX115S
To replace the SI50BX115S, order the SAI50BX115S. Verify the ISO 15552 mounting interface, 50mm bore, 115mm stroke, G1/4 port, and your specific mounting accessory. The -B rod is SUS304 stainless steel, and the -S magnet works with legacy CS1-B/DS1-B switches (the SAI uses current AirTAC switches). For sizing, neighboring bores are 40mm (628N push @0.5MPa) and 63mm (1559N push @0.5MPa). Note that 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 variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX115S
- ✓ 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 SI50BX115S FAQ
Yes, the SI50BX115S is discontinued. The direct replacement is the SAI50BX115S. It features the same ISO 15552 mounting interface, 50mm bore, 115mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly.
The bore is 50mm with a G1/4 air port. Force ratings are: 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical max of 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX115S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX115S replacement — usually within 7-8 hours.