English to Portuguese Tech/Engineering Petroleum Eng/Sci Treinamento - Instrumentação em Refinaria - Processos de Separação

O texto é referente a um treinamento em instrumentação para uma refinaria de petróleo. Segue fragmento:


2.2. Control System Operation
2.2.1. Simple control loops
Describe simple control loops. Include the following:
• Level – maintain a level setpoint
• Flow – maintain flow to a vessel
• Pressure – Maintain ***overhead drum Pressure***
• Temperature - maintain coil outlet pressure for a furnace

Discussion topics:
• Level
o The control objective is to maintain the drum level at setpoint
o This is accomplished by changing the flow leaving the drum
o If the level increases above setpoint, the controller will open the valve in the discharge line
• Flow
o The control objective is to maintain the feed rate at setpoint
o If the flow increases above the setpoint, then the controller adjustments will close the valve, and the flow PV will return to its setpoint
• Pressure
o The control objective is to maintain***overhead drum pressure*** at setpoint
o If the pressure decreases below the setpoint, the controller will close the valve, and the pressure PV will return to its setpoint