This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX210S, 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 SI50AX210S
The AirTAC Airtac SI50 Standard Cylinder SI50AX210S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 210mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX210S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke210 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX210S
- 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 SI50AX210S
The AirTAC SI50AX210S is a discontinued double-acting ISO 15552 profile cylinder featuring a 50mm bore, 210mm stroke, and a SUS420J2 stainless piston rod. Delivering 982N push force at 0.5MPa via a G1/4 port, it includes a built-in magnet for CS1-B/DS1-B switches. The direct replacement is the SAI50AX210S, matching the bore, stroke, force, port, and ISO 15552 mounting interface.
The SAI upgrade features a new 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 SI50AX210S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX210S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX210S |
| Bore size | Ø50 mm |
| Stroke | 210 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 SAI50AX210S 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 SAI50AX210S 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 SI50AX210S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×210 | 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 SI50AX210S Is Used
Stainless Rod Clamping
Utilizes the SUS420J2 rod for corrosion resistance when clamping machined parts in humid or lightly wet manufacturing cells.
Package Diverting
Provides 982N push at 0.5MPa to reliably divert medium-weight cartons on packaging lines at 30-800mm/s speeds.
Replacing the Airtac SI50 Standard Cylinder SI50AX210S with the SAI50AX210S
To replace the SI50AX210S, order the SAI50AX210S. Confirm the ISO 15552 mounting interface, the 50mm bore, 210mm stroke, G1/4 port, and the -S magnet for current AirTAC switches. If downsizing, a 40mm bore yields 628N push at 0.5MPa; if upsizing, a 63mm bore provides 1559N. For 210mm strokes, ensure guide rails prevent rod bending under side loads. 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 variant. The -A rod is SUS420J2 stainless steel.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX210S
- ✓ 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 SI50AX210S FAQ
Yes, the SI50AX210S is discontinued. The direct replacement is the SAI50AX210S. It matches the 50mm bore, 210mm stroke, G1/4 port, and ISO 15552 mounting interface, dropping directly into existing fixtures.
It features a G1/4 port. The 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX210S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX210S replacement — usually within 7-8 hours.