How is interlocking between valves represented on a PID diagram?
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As shown in the diagram: the hot oil control valve XV-516130A and the cold oil control valve XV-516130B. When the hot oil valve is open, the cold oil valve must remain closed; similarly, when the cold oil valve is open, the hot oil valve must remain closed. How can this be represented using interlock lines on a PID diagram?
On a PID diagram, you can represent the interlock relationship between valves by drawing a dashed line (interlock line). From the hot oil isolation valve XV-516130A to the cold oil isolation valve XV-516130B, an interlock symbol (usually a circle with the letters “IL” indicating Interlock) should be marked in the middle or at the end of the line, indicating that when one valve is opened, it will affect the status of the other valve. Similarly, a line also needs to be drawn from the cold oil valve XV-516130B to the hot oil valve XV-516130A, using the same labeling method. This clearly shows the interlocking relationship between the two valves on the diagram. .