Instrumentation in petrochemical industries

Instrumentation in petrochemical industries basically consists of flow meters, pressure transmitters, level sensors, temperature sensors, and analysis instruments.

The measurement of temperature is a vital part of instrumentation in petrochemical industries. Platinum Resistance Temperature Detectors (RTD's) are often used for their excellent temperature response. Thermocouples are used in locations that need a more durable sensor. Thermocouples come in many types.

A pressure to current converter (P/I converter) in petrochemical industries is used to measure the pressure developed by liquified petroleum gas (LPG), crude oil, petrol, and various other petroleum byproducts. In the P/I converter, the indicated pressure can be a digital or an analog form. The main advantage is that it can be directly shown on the control panel in the control room. This is true for temperature measurement also.

Because refined oil is volatile, it is important to know the quantity of oil being transported at numerous points along the pipeline. This requirement also holds for natural gas. Flowmeters are generally of vortex, positive displacement (PD), differential pressure (DP), coriolis, and ultrasonic varieties.

Petroleum and natural gas industries need very accurate level measurement. Besides traditional technologies like differential pressure level meters, radar, magnetostrictive, and magnetic float are also used extensively.

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