ORIFICE PLATE ASSEMBLY
- The Orifice Plate Metering system is suitable for measuring the rate of flow of steam, liquids and most gases.
- For steam and gas flowmetering applications, it is important to take account of changes in flowing density due to flowing pressure and temperature variations. If ignored these changes in flow density will cause significant measurement errors.
- Liquids being non- compressible do not suffer from this problem and generally density compensation is not required.
- Orifice plate is installed in the line at the point where the flow is to be measured. It produces a differential pressure proportional to the rate of flow.
- Isolation valves are used to isolate the impulse lines close to the orifice plate.
- DP transmitter assembly converts the differential pressure to a 4-20mA signal for retransmission to other equipment. It is supplied ready fitted with a 3 way manifold which acts as secondary isolation and pressure equalization valve.
- Pressure transmitter is installed in the impulse piping (high pressure side) and provides a pressure signal for density compensation.
- Temperature sensor and transmitter assembly is installed in the line upstream of the orifice plate and provides a temperature signal for density compensation.