Pressure control
Thread Content
What is the logic behind installing two pressure control valves at the equipment’s exhaust outlet? As shown in the figure below
This is a pressure range control system. If the pressure rises, first open the control valve on the equipment’s pipeline to reduce the pressure; if this does not suffice to lower the pressure, then open the control valve on the vent pipeline further. If the detection pressure drops, first reduce the vent flow; if the pressure still does not recover, then reduce the flow to the equipment.
Thank you, I understand. :hug:
Installing two pressure control valves at the gas outlet of the equipment is generally done to enhance safety and reliability. This setting is commonly referred to as “dual pressure protection”. When the gas pressure exceeds the set maximum pressure, the first pressure control valve will open and release some of the gas. If the first pressure control valve fails to function properly or cannot meet the gas flow requirements, the second pressure control valve will activate automatically and release more gas. This setting ensures that the device can still control the gas pressure in case of abnormalities, preventing overload and damage to the device while also protecting the safety of the operators. Dual pressure control can also improve the reliability of the equipment, as even if one pressure control valve fails, the other can still perform the pressure control function. .
Step-controlled operation: priority is given to device XXX; when the processing capacity is exceeded, evacuation is activated. Can a safety valve be used in place of the drain valve? Please, master, offer your guidance.
This is not split-control; these two valves have the same effect on pressure. It should be a simple control circuit, with the pressure setting for the vent control circuit being higher, while the pressure setting for the equipment is lower than that of the vent setting.
So how should these two valve fault switches be set?
Turn off the device’s fault function and proceed with venting; if the SIL rating is met, fault conditions are not taken into consideration
Shouldn’t the automatic valve have a fault switch? Can we still ignore failure scenarios for this venting system?