This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX185S, 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 SI50AX185S
The AirTAC Airtac SI50 Standard Cylinder SI50AX185S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 185mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX185S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke185 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX185S
- 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 SI50AX185S
The AirTAC SI50AX185S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 185mm stroke. It delivers 982 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50AX185S, a direct upgrade retaining the exact interface, bore, stroke, force, and mounting dimensions.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. This specific SKU includes a SUS420J2 stainless steel rod and a piston magnet for CS1-B/DS1-B switches.
Airtac SI50 Standard Cylinder SI50AX185S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX185S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX185S |
| Bore size | Ø50 mm |
| Stroke | 185 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 SAI50AX185S 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 SAI50AX185S 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 SI50AX185S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×185 | 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 SI50AX185S Is Used
Stainless Rod Actuation
Leveraging the SUS420J2 stainless piston rod for mid-force clamping and positioning in environments where moisture or minor corrosion is a concern.
185mm Stroke Diverting
Executing 185mm linear strokes to push or divert 40-50 kg workloads between adjacent conveyor lanes in material handling lines.
Replacing the Airtac SI50 Standard Cylinder SI50AX185S with the SAI50AX185S
To replace the SI50AX185S, order the SAI50AX185S and confirm the ISO 15552 mounting interface, 50mm bore, 185mm stroke, G1/4 port, and your specific mounting accessory. This unit has the -A SUS420J2 stainless rod and -S magnet for legacy CS1-B/DS1-B sensors (the SAI uses current AirTAC switches). If you need more force, the 63mm bore yields 1559 N push at 0.5 MPa; if less is required, the 40mm bore yields 628 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for held loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX185S
- ✓ 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 SI50AX185S FAQ
Yes, the SI50AX185S is discontinued. The direct replacement is the SAI50AX185S. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 185mm stroke, 982 N force, G1/4 port, and mounting interface.
This 50mm bore cylinder uses a G1/4 air port. The force 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 SAI50AX185S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX185S replacement — usually within 7-8 hours.