5 Important Considerations when Dealing with Control Valves
1. Flow Conditions inside a Control Valve
It is important to understand that there is a dynamic system inside a control valve. As the valve opens or closes, there will be continuous pressure changes inside the system. These changes in pressure result in changes in the flow of the fluid passing through the control valve. There is also the matter of heating and cooling of the material which may play a factor, from time to time. It is crucial that the engineer responsible for the selection of the valve understand these facets completely.
2. Difference in Flowing Conditions between Liquids and Gasses
When dealing with a liquid, the velocity of the fluid through a control valve will increase, as the cross-sectional area of the throat area of the control valve decreases. When dealing with gases, a totally different response comes into play. It is essential that you understand these variations in full.
3. Classification of Control Valves
Most people would classify a control valve according to its operation, which would be based on the movement of the actuator. Then, there would be the classification by means of functionality, which is related more to the type of control that is implemented. But, there is a further classification, and this would be specific to the actual application. This is particularly useful, when considering certain services.
4. Relationship between Pressure and Flow
Most piping systems present one of two scenarios, when dealing with pressure drops and flows. One scenario is more common than the other, and is to be found in most applications. The secret is to know how to deal with this, and what to do under various circumstances. Any engineer that ignores this scenario, runs the risk of having very poor control.
5. Cavitation
When does cavitation cause the most damage? Would it be at the start or the end of the cavitation process? What are the solutions to cavitation? Could something be done to the valve? Could something be done to the process? What about upstream and downstream considerations? Cavitation has the potential to do a lot of damage, and must be dealt with effectively.
These five aspects only pertain to the control valves. What about the actuators? To get these answers, and many other skill-sets pertaining to valves and actuators, you should not hesitate in enlisting for PetroKnowledge’s Control Valves and Actuators training course, to get all the correct information directly from a specialist. This training has been scheduled to run in multiple venues, and you would be advised to keep a very close eye on the Petroknowledge calendar.
