YOKOGAWA Vortex Flowmeters VY series

Vortex Flowmeters, Ideal for Steam Flow Measurement

Vortex flowmeters are highly versatile flowmeters that can measure liquids, gases, and steam over a wide range of temperatures and pressures. The advantages offered by this type of flowmeter make them better suited than other types to measuring steam flow.

Steam is the most commonly used high-temperature, high-pressure heat medium across a wide range of industries. For example, it is used for heating, distillation, and concentration in chemical plants; sterilization, disinfection, and cleaning in biotechnology, food, and pharmaceutical plants; and air conditioning in semiconductor plants and district heating/cooling plants, among many other applications. There are two types of steam: saturated steam and superheated steam. Saturated steam is a fluid with good thermal efficiency, but it is difficult to maintain saturation due to the pressure loss and heat radiation associated with steam transportation, so it is sometimes supplied in a superheated state at higher temperature and pressure. Vortex flowmeters are chosen as the best flowmeter for steam flow measurement at many facilities because they can measure the flow rate of even high-temperature, high-pressure steam, including superheated steam.

The vortex flowmeters in Yokogawa’s VY Series offer a wide measurable flow range of up to 400mm in connection size, as well as the ability to measure fluids at high temperatures of up to 450°C and high pressures of up to ASME Class 1500. In addition to excellent solidity and stability, the series has been added with remote maintenance and self-diagnostic functions that help ensure efficient maintenance, supporting long-term stability of plant operations and improved production efficiency.

Advantages of Introducing Vortex Flowmeters for Steam

This section describes the advantages of using vortex flowmeters for measuring steam flow, comparing them with orifice flowmeters (differential pressure flowmeters), which are used at many work sites.

Wide Rangeability to Accommodate Fluctuating Steam Flow Rate

A typical orifice flowmeter has a rangeability of around 5:1, which may result in a large error depending on the measurement range. By contrast, with a rangeability of 80:1, Vortex Flowmeter VY Series have a wide measurement range, with accuracy errors kept to a consistent level. This superior rangeability means that they can handle steam flow rates that vary with the season and operating load.

Low Pressure Loss Helps Ensure Stable Operation

Orifice flowmeters measure flow rate from the differential pressure created by the orifice (throttle valve), resulting in a pressure loss due to the orifice. On the other hand, vortex flowmeters have pressure loss due to vortex shedder bar, but it is smaller than that of orifices. Pressure loss causes a decrease in steam quality, which leads to higher costs due to energy loss. Therefore, a vortex flowmeter with small pressure loss is advantageous for maintaining steam quality and stable plant operation.

No Mechanical Moving Parts, Less Prone to Failure

Orifice flowmeters are easy to maintain because they are not in-line instruments, but they have many components such as an orifice (throttle valve), impulse piping, and a three-valve manifold and condensate pots, which require a large number of maintenance items. However, vortex flowmeters have a simple structure with no moving parts, and so are robust and less prone to failure. As such, their long-term robustness and low maintenance costs are a great help to plant operation.

The VY Series Is Recommended for the Following Users:

• Those who want to improve the efficiency and stability of device operations by using temperature and pressure compensations to measure steam flow rates with higher accuracy
• Those who want to minimize downtime by implementing predictive maintenance based on device conditions
• Those who want to reduce maintenance costs through component-based maintenance of device

Documents

• Spec Sheet
• Manual