This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX50, 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 SI50BX50
The AirTAC Airtac SI50 Standard Cylinder SI50BX50 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 50mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX50, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke50 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX50
- 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 SI50BX50
The AirTAC SI50BX50 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 50mm stroke, delivering 982 N push force at 0.5 MPa. The direct replacement is the SAI50BX50, which shares the exact ISO 15552 mounting interface, G1/4 port, and M16x1.5 rod thread. This SKU lacks a magnet, so it cannot accept position switches.
The SAI upgrade features a revised piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. If your application requires heat, Viton H seals raise the operating range to 0-150 C, and a SUS304 stainless rod (-B) offers corrosion resistance.
Airtac SI50 Standard Cylinder SI50BX50 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX50 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX50 |
| Bore size | Ø50 mm |
| Stroke | 50 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 SAI50BX50 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 SAI50BX50 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 SI50BX50
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×50 | 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 SI50BX50 Is Used
Clamping Fixtures
Secures workpieces during machining using 982 N of push force at 0.5 MPa, with the 50mm stroke providing rapid actuation.
Package Diverting
Short-stroke routing of medium-weight goods along material handling lines, taking advantage of the 30-800 mm/s speed range.
Gate Control
Actuates sorting gates and stops in logistics hubs, benefiting from the direct ISO 15552 profile barrel integration.
Replacing the Airtac SI50 Standard Cylinder SI50BX50 with the SAI50BX50
To replace the SI50BX50, order the SAI50BX50 and confirm your ISO 15552 mounting accessories (LB, FA, TC, etc.) and G1/4 air lines. Because this specific SKU has no magnet (-S), it cannot support legacy CS1-B/DS1-B sensors; order a magnet-equipped SAI if you need position feedback. A standard cylinder drifts without live air, so for load holding use an external pilot check valve or explore the SAIL lock and BSAI clamp-lock variants. For sizing, the 50mm bore yields 982 N push at 0.5 MPa; step down to a 40mm bore for 628 N or up to a 63mm bore for 1559 N. With a 50mm stroke, side-load risks are minimal, but always guide the load to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX50
- ✓ 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 SI50BX50 FAQ
Yes, the SI50BX50 is discontinued. The direct replacement is the SAI50BX50, which shares the same ISO 15552 mounting interface, 50mm bore, 50mm stroke, output force, and G1/4 port.
The 50mm bore features a G1/4 port and delivers 982 N push / 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a theoretical max of 200 kgf at 1.0 MPa.
Request a Quote for the SAI50BX50
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX50 replacement — usually within 7-8 hours.