What is a bypass control valve?
Pressure bypass valves serve to control pressure in a system by diverting a portion of the flow. Typically they bypass fluid from the outlet of a pump back to the reservoir. A pressure bypass valve is essentially a back pressure regulator.
How does a differential pressure bypass valve work?
The differential bypass valve is used in systems where heating loads may be excluded from the circuit as zone valves close. It controls the excess flow in the system by acting as a bypass while ensuring adequate flow to the remaining open circuits.
What size bypass should be installed around a pressure reducing valve?
The bypass line and valve should normally have a capacity at least equal to the calculated or required CV of the control valve, but not greater than twice the selected CV of the control valve. Bypass valves in sizes of 4 in. or fewer are usually globe valves that allow throttling.
How does a automatic bypass valve work?
An Automatic Bypass Valve (DU145) controls water flow in the Heating Circuit according to the water pressure across it and is used to maintain a minimum flow rate through the boiler and to limit circulation pressure when other water paths are closed.
How do I find my pressure reducing valve?
Your water pressure regulator is usually located right after the main shut-off valve for your water supply. This is typically found outside the house. Once you know where the shut-off valve is, you’ll find the water pressure regulator.
How does an equilibar pump bypass valve work?
The Equilibar precision back pressure regulator can provide pump bypass pressure control by using an air setpoint signal provided by a manual or electronic pressure regulator ( details ). This larger 2″ Equilibar® pressure bypass valve can be piloted manually or electronically to provide accurate pump pressure control.
Can a butterfly valve be used as a bypass valve?
Considering the bypass valve for throttling (flow control) The manual bypass valve is not 100% percent open during the operation. Thus, the operator should partially open the butterfly valve to get a flow capacity close to the control valve. Valve suppliers provide a flow characteristic curve based on the opening percentage of the valve.
Where are the gate and bypass valves located?
Two small (¾” or 1”) gate valves are located upstream and downstream of the control valve for drainage of two piping segments. There is a bypass valve (depicted in black) that is normally closed but will be opened for control valve maintenance.
How does a pressure bypass valve control pressure?
Considering the bypass valve for throttling (flow control) The manual bypass valve is not 100% percent open during the operation. Thus, the operator should partially open the butterfly valve to get a flow capacity close to the control valve. Valve suppliers provide a flow characteristic curve based on the opening percentage of the valve.
Two small (¾” or 1”) gate valves are located upstream and downstream of the control valve for drainage of two piping segments. There is a bypass valve (depicted in black) that is normally closed but will be opened for control valve maintenance.
How is the bypass valve a flow control device?
Even though the bypass valve is a pressure device, it’s acting as a flow control device to divert bypass flow to required system components. Therefore using the concept of a sub-system, the bypass valve and the positive displacement pump form a variable flow sub-system that will supply variable flow to the critical equipment on demand.
How are the bypass valves in an expander controlled?
The manufacturer of this system has developed a control strategy by which the bypass valves are controlled in the event of an expander trip. This enables the valves to precisely assume the position in which, in conjunction with the downstream orifice chambers, they precisely emulate the flow loss caused by the expander prior to the trip event.