This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X850S, 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 SI50X850S
The AirTAC Airtac SI50 Standard Cylinder SI50X850S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 850mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X850S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke850 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X850S
- 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 SI50X850S
The AirTAC SI50X850S is a discontinued double-acting ISO 15552 profile cylinder with an 850 mm stroke and a built-in piston magnet for CS1-B/DS1-B switches. Delivering 982 N push at 0.5 MPa, it features a 50 mm bore, G1/4 port and 30 mm adjustable cushions.
The direct replacement is the SAI50X850S, matching the ISO 15552 mounting interface, force and port. The SAI upgrades the piston seal to two Y-shaped elements for low start-up pressure. The SAI family also adds SAIL lock and BSAI clamp variants absent in the SI line.
Airtac SI50 Standard Cylinder SI50X850S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X850S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X850S |
| Bore size | Ø50 mm |
| Stroke | 850 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 SAI50X850S 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 SAI50X850S 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 SI50X850S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×850 | 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 SI50X850S Is Used
Long-Stroke Diversion
Pushes packages across a 850 mm conveyor lane using the 982 N push force at 0.5 MPa, requiring an external guide to prevent rod bending.
Material Ejection
Ejects molded parts from a press over an 850 mm distance, relying on the 30 mm adjustable cushions to decelerate the load.
Replacing the Airtac SI50 Standard Cylinder SI50X850S with the SAI50X850S
To replace the SI50X850S, order the SAI50X850S: it matches the ISO 15552 mounting interface, 50 mm bore, 850 mm stroke, G1/4 port, M16x1.5 rod thread and magnet. If you need more force, the 63 mm bore offers 1559 N push at 0.5 MPa; if less is required, the 40 mm bore provides 628 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates—so use a pilot check valve or SAIL/BSAI lock variant to hold loads. For this 850 mm stroke, use an external guide to prevent rod bending and side-load damage.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X850S
- ✓ 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 SI50X850S FAQ
Yes, the SI50X850S is discontinued. The direct replacement is the SAI50X850S. It is dimensionally interchangeable per ISO 15552, matching the 50 mm bore, 850 mm stroke, G1/4 port and mounting interface.
The G1/4 port bore delivers 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a theoretical max of 200 kgf at 1.0 MPa. It operates at 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X850S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X850S replacement — usually within 7-8 hours.