This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX290, 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 SI50BX290
The AirTAC Airtac SI50 Standard Cylinder SI50BX290 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 290mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX290, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke290 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX290
- 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 SI50BX290
The AirTAC SI50BX290 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore, 290mm stroke, Ø20mm rod and G1/4 port. Delivering 982N push force at 0.5MPa, it is replaced by the SAI50BX290. This direct upgrade shares identical ISO 15552 mounting dimensions, stroke and force.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure. This SKU lacks a magnet (-S), so it cannot take CS1-B/DS1-B sensors. The -B rod is SUS304 stainless steel.
Airtac SI50 Standard Cylinder SI50BX290 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX290 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX290 |
| Bore size | Ø50 mm |
| Stroke | 290 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 SAI50BX290 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 SAI50BX290 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 SI50BX290
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×290 | 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 SI50BX290 Is Used
Package Diversion
Pushes 50kg cartons at 90 degrees on a sorting line using the 982N push force, with the 290mm stroke clearing adjacent lanes.
Pallet Stop Gate
Acts as an indexing stop for inbound pallets, benefiting from the SUS304 stainless rod option to resist humidity and warehouse moisture.
Clamp Actuation
Secures mild steel workpieces during machining, taking advantage of the 30mm adjustable air cushions to soften end-of-stroke impacts.
Replacing the Airtac SI50 Standard Cylinder SI50BX290 with the SAI50BX290
To replace the SI50BX290, order the SAI50BX290. Verify the ISO 15552 interface, 50mm bore, 290mm stroke, G1/4 port (PT/G/NPT thread) and mounting. This SKU has no magnet, so it cannot accept position sensors; order a -S variant if sensing is needed. The 290mm stroke requires a guide to prevent rod bending and side-load wear. At 0.5MPa it yields 982N push (825N pull); the neighbouring 63mm bore offers 1559N if more force is needed. For load holding on air loss, use an external pilot check valve or the SAIL/BSAI lock variant, as cushions only decelerate.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX290
- ✓ 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 SI50BX290 FAQ
Yes, the SI50BX290 is discontinued. The direct replacement is the SAI50BX290. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 290mm stroke, 982N force, G1/4 port and mounting fixtures.
The G1/4 port bore delivers 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, and a theoretical max of 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX290
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX290 replacement — usually within 7-8 hours.