This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX185, 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 SI50AX185
The AirTAC SI50 Standard Cylinder SI50AX185 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 SAI50AX185, 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 → SAI50AX185
- 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 SI50AX185
The AirTAC SI50AX185 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 185 mm stroke. It delivers 982 N push force at 0.5 MPa via a G1/4 port. The direct replacement is the SAI50AX185, matching the exact mounting interface, force, and stroke.
This SKU features a SUS420J2 stainless steel rod (A option) but lacks a magnet, so it cannot accept CS1-B/DS1-B sensors. The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure.
Airtac SI50 Standard Cylinder SI50AX185 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX185 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX185 |
| 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 SAI50AX185 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 SAI50AX185 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 SI50AX185
| 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 SI50AX185 Is Used
Mid-Tonnage Clamping
Provides 982 N of push force at 0.5 MPa, ideal for securing medium-sized machined components during milling or drilling operations.
Package Diverting
Executes 185 mm strokes to push moderate-weight cartons off a main conveyor belt line into secondary sorting chutes.
Replacing the Airtac SI50 Standard Cylinder SI50AX185 with the SAI50AX185
To replace the SI50AX185, order the SAI50AX185. Confirm the ISO 15552 mounting accessory (LB, FA, TC, etc.), the G1/4 port, and the M16x1.5 rod thread. Because this SKU has no -S magnet, it cannot support position sensing; order a magnet-equipped SAI if switches are needed. For sizing, the 50 mm bore gives 982 N push at 0.5 MPa; step down to a 40 mm bore (628 N) for lighter loads or up to a 63 mm bore (1559 N) for heavier tasks. Note that a standard 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 → SAI50AX185
- ✓ 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 SI50AX185 FAQ
Yes, the SI50AX185 is discontinued. The direct replacement is the AirTAC SAI50AX185. It is dimensionally interchangeable per ISO 15552, matching the 50 mm bore, 185 mm stroke, 982 N force, G1/4 port, and mounting interface.
It operates at 30-800 mm/s. Force output is 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, with a theoretical maximum of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX185
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX185 replacement — usually within 7-8 hours.