This is a vertical single acting reciprocating type Engine. It is available in two models single stage and double stage as per user requirement. This produces the cold required for operating the plant. The high-pressure air enters through inlet valve at the start of the downward stroke of the piston and expands.During upward stroke outlet valve opens and the expanded air pushed outside. The Electric Motor is used to start the engine initially, thereafter the engine is moved by the air pressure itself and during which time, the engine motor retains the speed by acting as a brake. Since work is done by air in rotating the Flywheel, it loses its heat content (enthalpy). Thus the air gets cooled. This cooling is more than the expansion valves. The temperature drop in this engine in -50°C to -70°C depending on air pressure, temperature and inlet cam position.
The Expansion Engine can be considered as three major units:
- The drive unit.
- The Cylinder Unit for air expansion
- The Hydraulic Systems for operating the Valves.
Technical Data –
| Specifications | 80/100/130M3/Hr Oxygen Plant | 170/200 M3/Hr Oxygen Plant |
| Type of Expansion Engine | Vertical Single Acting | Vertical Single Acting |
| Diameter of cylinder bore | 90 mm | 80 mm |
| No. Of Cylinders | 1 | 2 |
| Piston stroke | 150 mm | 125 mm |
| Speed of Engine | 200 RPM | 200 RPM |
| Inlet valve opening time came setting | 8 positions | 8 positions |
| Piston head clearance | 1.2 +/- 0.2 mm | 1.2 +/- 0.2 mm |
| Inlet valve pastel clearance | 0.4 to 0.5 mm | 0.4 to 0.5 mm |
| Inlet air pressure | 60 kgs/cm2g | 60 kgs/cm2g |
| Outlet air pressure | 5 kgs/cm2g | 5 kgs/cm2g |
| Throughput volume at 40 kgs/cm2 | 400 Nm3 / hr. | 700-800 Nm3 /hr |