DP flowmeters also known as differential
pressure flowmeters are used for measuring the liquid flow in a pipe precisely.
These devices employ Bernoulli’s equation to perform the measurement process. A
constriction is introduced in the pipe that leads to a pressure drop across the
flowmeter. The pressure drop gets higher as the flow of the liquid increases.
The flowmeter’s downstream and upstream pressures are directed to the
transmitter by the impulse piping methodology. The transmitter gauges the
differential pressure to identify the fluid flow. Around 25% of flowmeters
being used worldwide are using this technology. Here are various types of
differential flowmeters that you can come across today
Venturi Flowmeters
Two reasons, namely reliability, and
simplicity make Venturi flowmeters the best choice for applications where lower
pressure drops or higher turndown ratios are applicable. This flow rate is
measured lowering the cross-sectional flow area in the flow path, which in turn
creates a pressure difference. Since there is no foreign material buildup, this
type of DP flowmeter is extensively utilized in streams that are dirty.
V-Cone Flowmeters
For creating a circular area for fluid
passage V-Cone flowmeters comprise a cone element that is v-shaped. It is
located in the pipe's central part. Compared to other kinds of pressure
flowmeters, the v-cone model has reduced permanent pressure loss. Before and
after the cone, it gauges pressure using a DP transmitter. You can use this
model for measuring steam, liquids, and gases.
Orifice Plate Flowmeters
The orifice plate flow meter comes with a
vent in the flat metal plate. The installation of this flowmeter is done
vertically to the natural stream. Based on the pressure difference between the
upstream and downstream sides, an orifice flowmeter measures the fluid flow in
a partially obstructed circular pipe. The orifice plate flow meter is used to
gauge steam, gas or liquid. Being an affordable and simple device, it can be
delivered for any application.
Pitot-static tube Flowmeters
As the name suggests, these flowmeters
contain an annular and pitot tube along with invariable pressure ports. This
device employs a DP transmitter to gauge the pressure between the two ports.
Liquids or gases can be used for measuring gases or liquids.
Nozzle Flowmeters
Though nozzle and orifice have the same
level of permanent pressure loss, nozzle flowmeter has the extra ability to
deal with abrasive and dirty fluids. It uses a DP transmitter to gauge pressure
between the flow stream in the pipe and nozzle. Gas or liquids can be measured
using nozzle flowmeters.
Wedge Flowmeters
A wedge flow meter is highly useful to
measure semi-liquid mixtures. It is equipped with an element that is
wedge-shaped and sits vertical to the flow at the conduit top. The bottom part
stays unhindered. The pressure that exists between the wedge sides is measured
using a DP transmitter.
Elbow Flowmeters
A centrifugal force is created the pipe
elbow's outside walls and inside diameter to generate a differential pressure.
The elbow flow meter gauges the pressure existing between the walls using a DP
transmitter. You can use it as a liquid or gas flow meter.
Balanced flow meter
Balanced flow meter is a kind of multi-hole
orifice plate, this kind of differential pressure flow meter developed the traditional
orifice flow meter, has obvious advantages : high accuracy ,low requirement for
straight pipelines when mounting, very low pressure loss , large turn down ratio,good
choice for high temperature and high pressure fluids flow rate measurement
Conditioning Orifice Plate flow meter
It is also developed from traditional orifice
plate flow meter, it has 4 equally holes
instead of one hole, it does not have strict straight pipelines when
installation,also has better accuracy comparing to traditional orifice plate
flow meter.