WHAT IS RATIO CONTROL ?
RATIO CONTROL A ratio controller is a special type of feed forward controller where disturbances are measured and their ratio is held at a desired...
Pressure Relief valves
Overview: The Relief valves are safety valves prevent equipment damage by relieving accidental over-pressurization of fluid systems. The relief valves protects instruments such as motors,...
Orifice Plates Flowmeters
The Orifice plate is differential pressure flow measurement device. An orifice is simply a smooth disc with a round, sharp-edged inflow aperture and mounting rings. Principle:...
Basics of Pressure Scales
Introduction There are three pressure scales used for measuring pressure. The Absolute pressure scale The Gauge pressure scale The Vacuum pressure scale In the...
What are pneumatic controllers ?
Introduction A controller is a device that senses differences between a desired condition and measured condition in a process. .The controller will reduce this difference...
Magnetic flowmeter
Magnetic flowmeters are velocity type of flowmeters. An electromagnetic flowmeter can work with almost all liquids and slurries, as long as the liquid being measured is...
BASICS OF AN INSTRUMENT AIR SUPPLY SYSTEM
Introduction The air used must be cleaned, dry and oil-free to ensure that small lines, restrictions and nozzles will not be plugged by dirt, oil...
what are pressure relief valves?
INTRODUCTION Protection against over pressure is one of the most important design tasks in the chemical, petrochemical, oil, and gas industries.pressure relief valves are such...
what is cascade control?
A simple control system drawn in block diagram form looks like this: Information from the measuring device (e.g. transmitter) goes to the controller, then to...
Strain gauge pressure measurement
The strain gauge is a passive transducer used to pressure, which converts the change in pressure into a change in resistance as the metal strain...