NKCS EXPANSION ENGINE:
Single Acting/ Vertical/ Reciprocating type Expansion Engine consists of three major units such as drive unit, cylinder unit for air expansion and hydraulic system for operating the valves. The Expansion Engine has an extended crankshaft, which enables the accommodation of the cam box. The Expansion Engine is available in a single acting, vertical and reciprocating type designs. Single Acting/ Vertical/ Reciprocating type Expansion Engine finds application in various industrial sectors.
It is a vertical single acting dry running with hydraulic valve control, bursting disc for safety, complete with flywheel, pressure gauges, motor, motor pulley, V belts, belt guard, Slide Rails, inter connecting copper Pipes (Inlet and Outlet with A.S.U.) but excluding motor starter.
The Expansion Engine can be considered as three major units:
1) The drive unit.
2) The Cylinder Unit for air expansion and
3) The Hydraulic Systems for operating the Valves.
The High Pressure Expansion Engine is used for liquid Plants.
WORKING:
In downward stroke air enters the cylinder and expands. In the upward stroke the expanded air is pushed outside. The electric motor is used to start the machine. 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 that of an expansion in an Expansion valve.
An elementary factor for the function of an expansion engine is to use dry and Carbon Di-Oxide free air, as otherwise, ice and dry ice will form on valve seats, causing mal-function. The approximate temperature drop across Expansion Engine is 50 to 70°C, depending on inlet air pressure, temperature and inlet cam position.
TECHNICAL DATA:
| TECHNICAL DATA | NKCS 80 | NKCS 100 | NKCS 200 | NKCS 300 |
| No. of Cylinders | 1 | 1 | 2 | 2 |
| Diameter of Cylinder Bore | 70 mm | 80 mm | 85 mm | 90 mm |
| Piston Stroke | 125 mm | 125 mm | 125 mm | 125 mm |
| Speed | 210 RPM | 210 RPM | 210 RPM | 210 RPM |
| Inlet Air Pressure | 60 kgs/cm2 | 60kgs/cm2 | 60kgs/cm2 | 60kgs/cm2 |
| Outlet Air Pressure | 5 kgs/cm2 | 5 kgs/cm2 | 5 kgs/cm2 | 5 kgs/cm2 |
| Throughput Volume at 60 kgs/cm2 and 80 C (about) | 300 Ncu.m./Hr | 400 Ncu.m./Hr | 560 Ncu.m./Hr | 828 NM3./Hr |
| Throughput Volume at 50 kgs/cm2 and -750 C (about) | 120-390 Ncu.m./Hr | 200-400 Ncu.m./Hr | 400-560 Ncu.m./Hr | 550-830 Ncu.m./Hr |
| Inlet Valve opening time cam setting position | 8 | 8 | 8 | 8 |
| Power required or supplied | 7.5 KW | 7.5 KW | 15 KW | 30 KW |
| Piston Head Clear | 1.2 – or + 0.2 mm | 1.2 -or + 0.2 mm | 1.2 -or + 0.2 mm | 1.2 + 0.2 mm |
| Inlet Valve Pestel Clearance | 0.4 to 0.5 mm | 0.4 to 0.5 mm | 0.4 to 0.5 mm | 0.4 to 0.5 mm |
| Outlet Valve Pestel Clearance | 0.3 to 0.4 mm | 0.3 to 0.4 mm | 0.3 to 0.4 mm | 0.3 to 0.4 mm |
