Introduction
A pressure transmitter is an instrument used to measure the pressure of fluids in different industrial applications. It is an essential component of the measuring and control system used in various industries such as oil and gas, chemical, food and beverage, etc. The primary function of a pressure transmitter is to convert the applied pressure into an electrical signal that can be transmitted to a monitoring system or controller.
Pressure transmitters come in different types, and each type is suitable for specific application requirements. In this article, we will discuss the four types of pressure transmitters, their features, and applications.
Type 1: Absolute Pressure Transmitter
The first type of pressure transmitter is the absolute pressure transmitter. This type of transmitter measures pressure in reference to the absolute vacuum. It takes the atmospheric pressure into account as well. Absolute pressure transmitters are widely used in applications that require precise measurements of pressures in vacuum processes, such as chemical and petrochemical applications.
One of the significant advantages of absolute pressure transmitters is their ability to work effectively in a wide range of pressure and temperature conditions. They are typically made of stainless steel and are highly durable, making them ideal for use in harsh environments.
The use of absolute pressure transmitters is prevalent in oil and gas industries, as they are suited for process control in oil refineries, distillation towers, and chemical plants.
Type 2: Gauge Pressure Transmitter
The second type of pressure transmitter is the gauge pressure transmitter. A gauge pressure transmitter measures pressure in reference to the atmospheric pressure, which is considered to be zero. Gauge pressure transmitters are commonly used in applications that involve measuring the pressure of gases and liquids, such as in pipelines, hydraulic systems, and in the food and beverage industry.
The use of gauge pressure transmitters is widespread in gas and oil industries, where they are used for monitoring and controlling the pressure of liquids and gases in pipelines and storage tanks.
One of the advantages of gauge pressure transmitters is their versatility, as they can function effectively in moderate temperature and pressure ranges. They can also be fitted with various types of sensors to improve their accuracy and reliability.
Type 3: Differential Pressure Transmitter
The third type of pressure transmitter is the differential pressure transmitter. A differential pressure transmitter measures the difference in pressure between two points. It is commonly used in industrial applications that involve monitoring flow rates, such as in HVAC systems, chemical production, and water treatment plants.
Differential pressure transmitters consist of two pressure sensors and a transducer that converts the pressure difference into an electrical signal. They are available in various types, including wet and dry differential pressure transmitters.
Wet differential pressure transmitters are suitable for applications where the fluid pressure being measured is corrosive or at high temperature conditions. Dry differential pressure transmitters, on the other hand, are used in applications where the fluid pressure being measured is clean.
One of the significant advantages of differential pressure transmitters is their ability to monitor non-Newtonian fluids, making them ideal for measuring fluid in pipelines and storage tanks.
Type 4: Sealed Pressure Transmitter
The fourth type of pressure transmitter is the sealed pressure transmitter. A sealed pressure transmitter is a type of gauge pressure transmitter with a sealed housing. The housing prevents the pressure from entering the enclosure. Sealed pressure transmitters are commonly used in harsh environments where moisture, chemicals, and dust can affect the accuracy and reliability of the readings.
Sealed pressure transmitters are widely used in the oil and gas industry, where they are used for monitoring and controlling the pressure of liquids and gases in pipelines, refineries, and storage tanks.
One of the significant advantages of sealed pressure transmitters is their ability to function effectively in high-pressure and temperature conditions. They are also highly durable, making them ideal for use in harsh environments where moisture and dirt can affect the readings.
Conclusion
The four types of pressure transmitters discussed in this article are absolute pressure, gauge pressure, differential pressure, and sealed pressure transmitters. Each type of pressure transmitter is suitable for specific applications, and their features and advantages make them ideal for use in various industries.
When selecting a pressure transmitter, it is essential to consider the environmental conditions, pressure range, accuracy, and reliability of the transmitter. Proper installation and calibration are also essential for accurate and reliable pressure readings.