This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX120, 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 SI50AX120
The AirTAC Airtac SI50 Standard Cylinder SI50AX120 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 120mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX120, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke120 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX120
- 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 SI50AX120
The AirTAC SI50AX120 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 120mm stroke. It delivers 982 N push and 825 N pull at 0.5 MPa through a G1/4 port. The direct replacement is the SAI50AX120, matching the interface, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU lacks a magnet (-S) and cannot take a sensor. The -A rod is SUS420J2 stainless.
Airtac SI50 Standard Cylinder SI50AX120 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX120 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX120 |
| Bore size | Ø50 mm |
| Stroke | 120 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 SAI50AX120 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 SAI50AX120 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 SI50AX120
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×120 | 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 SI50AX120 Is Used
Package Diverting
Pushes medium-weight cartons off a main conveyor line using the 982 N push force at 0.5 MPa.
Clamp Actuation
Holds aluminium extrusions in place for CNC machining with the SUS420J2 stainless rod option.
Pallet Stopper
Acts as a pneumatic stop for incoming pallets, absorbing impact via the 30mm adjustable air cushion.
Replacing the Airtac SI50 Standard Cylinder SI50AX120 with the SAI50AX120
To replace the SI50AX120, order the SAI50AX120. Confirm the ISO 15552 mounting interface, 50mm bore, 120mm stroke, G1/4 port (PT/G/NPT), and your specific mounting accessory. Because this SKU has no magnet, it cannot accept a CS1-B/DS1-B sensor; add the -S suffix if position sensing is needed. For sizing, a 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 pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX120
- ✓ 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 SI50AX120 FAQ
Yes, the AirTAC SI50AX120 is discontinued. The direct replacement is the SAI50AX120. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 120mm stroke, G1/4 port, and mounting interface.
The G1/4 port supplies 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, 1767 N push at 0.9 MPa, and a theoretical max of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX120
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX120 replacement — usually within 7-8 hours.