This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX220S, 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 SI50BX220S
The AirTAC Airtac SI50 Standard Cylinder SI50BX220S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 220mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX220S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke220 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX220S
- 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 SI50BX220S
The AirTAC SI50BX220S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 220mm stroke. It features a SUS304 stainless piston rod (-B) and a built-in magnet (-S) for legacy CS1-B/DS1-B switches. Delivering 982 N push force at 0.5 MPa via a G1/4 port, the direct replacement is the SAI50BX220S.
The SAI upgrade retains the same ISO 15552 mounting interface and dimensions but introduces an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The SAI family also adds SAIL, SAIF and BSAI lock variants the SI lacked.
Airtac SI50 Standard Cylinder SI50BX220S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX220S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX220S |
| Bore size | Ø50 mm |
| Stroke | 220 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 SAI50BX220S 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 SAI50BX220S 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 SI50BX220S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×220 | 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 SI50BX220S Is Used
Stainless Rod Diverters
Ideal for pushing packages on conveyors where the SUS304 rod resists moisture and corrosion.
Corrosive Environment Actuators
Drives clamps and stops in washdown areas, relying on the robust stainless piston rod.
Replacing the Airtac SI50 Standard Cylinder SI50BX220S with the SAI50BX220S
To replace the SI50BX220S, order the SAI50BX220S. Verify the ISO 15552 mounting interface, 50mm bore, 220mm stroke, G1/4 port (PT/G/NPT thread options), and your specific mounting accessory. The -B denotes a SUS304 stainless rod, and -S confirms the magnet for current AirTAC switches. Sizing both ways: a neighbouring 40mm bore yields 628 N push at 0.5 MPa, while a 63mm bore yields 1559 N. 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. At 220mm stroke, ensure guide alignment to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX220S
- ✓ 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 SI50BX220S FAQ
Yes, the SI50BX220S is discontinued. The direct replacement is the SAI50BX220S. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 220mm stroke, 982 N force, G1/4 port, and mounting interface.
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 a theoretical maximum of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX220S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX220S replacement — usually within 7-8 hours.