This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X185S, 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 SI50X185S
The AirTAC Airtac SI50 Standard Cylinder SI50X185S 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 SAI50X185S, 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 → SAI50X185S
- 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 SI50X185S
The AirTAC SI50X185S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 185mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. AirTAC replaced this with the SAI50X185S, a direct upgrade retaining the same interface, output, and mounting.
The SAI features an upgraded two Y-shaped piston seal for low start-up pressure. The SI -S magnet works with CS1-B/DS1-B sensors, while SAIL/BSAI lock variants cover load holding.
Airtac SI50 Standard Cylinder SI50X185S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X185S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X185S |
| 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 SAI50X185S 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 SAI50X185S 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 SI50X185S
| 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 SI50X185S Is Used
Package Diversion
Actuates routing gates on packaging lines where 982N push force at 0.5MPa easily deflects standard totes.
Clamp Actuation
Provides reliable holding pressure for mid-sized machining fixtures, utilizing the 825N pull force at 0.5MPa.
Replacing the Airtac SI50 Standard Cylinder SI50X185S with the SAI50X185S
To replace the SI50X185S, order the SAI50X185S. Confirm the ISO 15552 mounting interface, 50mm bore, 185mm stroke, G1/4 port (PT/G/NPT), and the -S magnet for CS1-B/DS1-B switches. Sizing both ways: a 40mm bore yields 628N push at 0.5MPa, while a 63mm bore yields 1559N. Note that a plain cylinder drifts without live air; use the SAIL or BSAI lock variant, or an external pilot check valve, to hold loads. The 185mm stroke is under 300mm, so rod-bending side-load risks are minimal, but always guide the load.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X185S
- ✓ 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 SI50X185S FAQ
Yes, the SI50X185S is discontinued. The direct replacement is the SAI50X185S. It shares the same ISO 15552 mounting interface, 50mm bore, 185mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
This double-acting cylinder uses a G1/4 air port. At 0.5MPa it provides 982N push and 825N pull force. At 0.7MPa push is 1374N, and maximum theoretical force is 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X185S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X185S replacement — usually within 7-8 hours.