This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX275, 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 SI50AX275
The AirTAC SI50 Standard Cylinder SI50AX275 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 275mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX275, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke275 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX275
- 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 SI50AX275
The AirTAC SI50AX275 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore, 275mm stroke, and a SUS420J2 stainless steel rod. It delivers 982 N push force at 0.5 MPa through a G1/4 port. The direct replacement is the SAI50AX275, which retains the exact same mounting interface, output force, and cushioning.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. Note this SKU lacks a magnet, so it cannot accept CS1-B/DS1-B sensors. For higher heat, Viton H seals raise the temperature limit to 150 C.
Airtac SI50 Standard Cylinder SI50AX275 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX275 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX275 |
| Bore size | Ø50 mm |
| Stroke | 275 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 SAI50AX275 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 SAI50AX275 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 SI50AX275
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×275 | 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 SI50AX275 Is Used
Diverting Gate Actuation
Provides the 982 N push force needed to pivot heavy sorting gates on packaging lines, with the 275mm stroke allowing full lane redirection.
Stainless Rod Clamping
The SUS420J2 rod option excels in mildly corrosive machining environments where coolant mist would degrade standard carbon steel.
Replacing the Airtac SI50 Standard Cylinder SI50AX275 with the SAI50AX275
To replace the SI50AX275, order the SAI50AX275 and confirm the ISO 15552 mounting interface, 50mm bore, 275mm stroke, G1/4 port, and SUS420J2 rod. Since this is a non-magnetized SKU, it cannot support position sensing. If you need to downsize, a 40mm bore yields 628 N push at 0.5 MPa; if upsizing, a 63mm bore provides 1559 N. At 275mm stroke, use guide rails to prevent rod bending and side-load damage. A plain cylinder drifts on air loss—the cushion only decelerates—so add a pilot check valve or use the SAIL/BSAI lock variants for load holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX275
- ✓ 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 SI50AX275 FAQ
Yes, the SI50AX275 is discontinued. The direct replacement is the SAI50AX275. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 275mm stroke, G1/4 port, and mounting fixtures perfectly.
This 50mm bore cylinder uses a G1/4 port. The thrust ratings are: 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 maximum of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX275
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX275 replacement — usually within 7-8 hours.