This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X150S, 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 SI50X150S
The AirTAC Airtac SI50 Standard Cylinder SI50X150S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 150mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X150S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke150 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X150S
- 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 SI50X150S
The AirTAC SI50X150S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 150mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. AirTAC replaced this unit with the SAI50X150S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, output force, port size and accessories.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The original -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family introduces SAIL, SAIF and BSAI lock variants previously unavailable.
Airtac SI50 Standard Cylinder SI50X150S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X150S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X150S |
| Bore size | Ø50 mm |
| Stroke | 150 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 SAI50X150S 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 SAI50X150S 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 SI50X150S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×150 | 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 SI50X150S Is Used
Package Diversion
Actuates routing gates on packaging lines where 982N push force reliably redirects moderate-weight cartons at speed.
Clamp Actuation
Provides 825N pull force to hold workpieces in CNC machining fixtures, utilizing the 150mm stroke for varied part sizes.
Replacing the Airtac SI50 Standard Cylinder SI50X150S with the SAI50X150S
To replace the SI50X150S, order the SAI50X150S. Confirm the ISO 15552 mounting interface (LB, FA, CA, TC, etc.), the 50mm bore, 150mm stroke, G1/4 port (PT/G/NPT thread options) and the -S magnet for current AirTAC switches. If you need more force, the neighbouring 63mm bore yields 1559N push at 0.5MPa; if less is required, the 40mm bore gives 628N. A plain cylinder drifts on air loss because the air cushion only decelerates near stroke end. For load holding, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variant. Because the stroke is under 300mm, side-load rod-bending risks are minimal, but always guide the load.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X150S
- ✓ 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 SI50X150S FAQ
Yes, the SI50X150S is discontinued. The direct replacement is the SAI50X150S. It shares the same ISO 15552 mounting interface, 50mm bore, 150mm stroke, output force, G1/4 port and mounting accessories, fitting directly into existing fixtures.
This double-acting cylinder has a G1/4 air port. It delivers 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical maximum of 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X150S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X150S replacement — usually within 7-8 hours.