Progressive Control Valve Sequence
Another form of control valve sequencing is used to expand the operating range of flow control for some fluid beyond
Exclusive Control Valve Sequence
Other applications for split-ranged control valves call for a form of valve sequencing where both valves are fully closed at
Complementary Control Valve Sequence
The first type of control valve sequencing is a mode where two valves serve to proportion a mixture of two
Control Valve Positioners
The reason why a pneumatic control valve’s stem position corresponds linearly to the amount of air pressure applied to the
Valve Seat Leakage Test
In some process applications, it is important that the control valve be able to completely stop fluid flow when placed
Bellows Seal Valve Working Principle
A completely different approach to packing is a device called a bellows seal : an accordion-like metal tube fastened to
What is Valve Packing ?
Regardless of valve type, all stem-actuated control valves require some form of seal allowing motion of the stem from some
Laminar Flow Meter Working Principle
A unique form of differential pressure-based flow measurement deserves its own section in this flow measurement chapter, and that is laminar flow meter.
RTD Calibration
R.T.D. Accuracy checks for a resistance temperature detector/device (RTD) is often necessary to validate the accuracy of a new RTD.
Thermocouple Calibration
Thermocouples Thermocouples measure temperature and are used quite often in process controls. How They Work When wires of two different