Excellent silicon wafer, Wheatstone-bridge and pressure-sensitive diaphragm are sealed in a steel house filled with glycerine or silicone to encase the interior components of the sensor. diaphragm sensors are very sensitive to rapid pressure changes. -- they are commonly used in very corrosive environments or with extreme over-pressure situations.
SENSOR SELECTION CRITERIA, A GOOD FLAT PRESSURE SENSOR SHOULD HAVE THE PROS UNDER BELOW
1. Fine sealing, available in the viscous medium and easy to clean up the residual stains.
2.High measurement accuracy, good stability,
3. small size and convenient installation.
4. high-cost performance.
Diaphragm pressure transducer are able to give accurate and precise readings for controller to control electronic instrument to prevent overflow or avoid empty run damage, which are good for energy effectively and achieve long-term operating, However, some factors influence the suitability of pressure sensors: the characteristics of the measured media, environmental conditions, pressure range, and the level of precision in measurements made.
CHARACTERISTICS OF THE MEASURED MEDIA
The flat pressure sensor(elastic element) will be exposed to the medias used in the measuring process, therefore corrosion resistant metal diaphragms or foil are optimal for very harsh environments. The materials which might react with the process substances or degrade in corrosive media are unsuitable for use in the sensor.
ENVIRONMENT CONDITIONS
Corrosive environments, vibrations near pipe fittings, or extreme high temperatures are vital for the selecting of pressure sensors for the purpose of protect the and facilities in very harsh environments.
PRESSURE RANGE
Pressure sensors or pressure transducers are designed with a limit of certain pressure ranges for different equipment and facilities. Because Large and complex equipment requires multiple sensors with high accuracy, but small civilian equipment may only need one sensor with ordinary accuracy, to choose the right pressure transducer is very important in the process.
SENSITIVITY
The more precise the pressure transducer, the more expensive it is, thus choosing pressure transducers that available to reach the wanted precision at the most suitable price is quite worthy. The compromise between accuracy and measuring time is also quite important, is unadvisable to use sensors that take a lot of time to give accurate pressure readings, High accuracy measure reading at short measuring time is viable when the price is very high.
OLD SCHOOL PRESSURE MEASURING METHODS
Old school pressure measuring methods have been developed and utilized in decades ago and some of them are still applied in some uncomplicated, small sized and low precision equipment.
1.Height of Liquid in Column
The height of a liquid with known density is used to measure pressure. Using the equation P = ρgh, the gauge pressure can be easily calculated. These types of pressure measuring devices are usually called manometers. Mercury is used when you desire higher pressure measurements and not as great sensitivity.
2.Elastic Distortion
This pressure measuring method is based on the idea that deformation of an elastic material is directly proportional to the pressure being measured. Such as Bourdon-tubes or Bourdon Gauge.
3.Bellow gauge
Bellows elements are cylindrical in shape and contain many folds. They deform in the axial direction (compression or expansion) with changes in pressure. Bellows can only be applied to low pressures with low accuracy
4.Mechanical Strain type
Electrical methods used for measuring pressure utilize the idea that dimensional changes in a wire affect the electrical resistance to the conductor. These devices that use the change in resistance of the wire are called strain gauges.
TYPES OF PRESSURE
Pressure is defined as force per unit area and is in calculate units of psi, Pa, Kpa, and Bar. Three type of reference pressures are used in pressure measuring industries.
Absolute pressure -Pressure measured in vacuum zero pressure environment, atomospheric pressure plus gauge pressure.
Gauge Pressure - Pressure measured in ambient atmosphere. absolute pressure minus atmospheric pressure.
Differential Pressure - pressure measurement based on same medias or in same facility in two positions.
APPLICATION
Flat pressure sensors are widely used in a variety of industries such as petrochemical, water purify ink, paint, mud and Dairy products with a certain possibility of viscous measurement.
LEFOO provide pressure differential monitor, differential pressure transmitter, peristaltic liquid pump, ro water purifier pump, etc. Contact us to know more.
Location : No.118, Changda Road, Linping Street, Yuhang District, Hangzhou, Zhejiang, 311100 China, 311100 Yuhang District,
Contact : group lefoo, 0571 89363666