This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX50S, 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 SI50AX50S
The AirTAC Airtac SI50 Standard Cylinder SI50AX50S 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 SAI50AX50S, 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 → SAI50AX50S
- 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 SI50AX50S
The AirTAC SI50AX50S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore, 50mm stroke, and an SUS420J2 stainless steel rod. Delivering 982 N push at 0.5 MPa, it features a G1/4 port and M16x1.5 rod thread. The direct replacement is the SAI50AX50S, matching the exact interface, force, and mounting.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The original -S magnet supports legacy CS1-B/DS1-B sensors, while a Viton H seal option extends heat to 150 C.
Airtac SI50 Standard Cylinder SI50AX50S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX50S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX50S |
| 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 SAI50AX50S 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 SAI50AX50S 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 SI50AX50S
| 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 SI50AX50S Is Used
Stainless Rod Clamping
Ideal for short-stroke clamping of mid-weight assemblies where the SUS420J2 rod resists moisture and corrosion.
Transfer Line Diversion
Provides reliable 50mm diverting force on packaging lines, utilizing the 982 N thrust at 0.5 MPa.
Replacing the Airtac SI50 Standard Cylinder SI50AX50S with the SAI50AX50S
To replace the SI50AX50S, order the SAI50AX50S. Verify the ISO 15552 mounting interface, G1/4 port, 50mm stroke, and the -S magnet for current AirTAC switches. The -A rod is SUS420J2 stainless steel. Sizing both ways: this 50mm bore yields 982 N push at 0.5 MPa; a neighbouring 40mm bore gives 628 N, while a 63mm bore provides 1559 N. For load holding, note that a plain cylinder drifts on air loss—the cushion only decelerates. Use an external pilot check valve or the SAIL/BSAI lock variants. The SAI family also adds the SAIF integrated valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX50S
- ✓ 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 SI50AX50S FAQ
Yes, the SI50AX50S is discontinued. The direct replacement is the SAI50AX50S. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 50mm stroke, G1/4 port, and mounting fixtures.
The G1/4 port bore delivers a push of 982 N and pull of 825 N at 0.5 MPa. At 0.7 MPa push is 1374 N, and the theoretical maximum force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX50S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX50S replacement — usually within 7-8 hours.