Automatic Recirculation Valve
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Automatic Recirculation Valves

Automatic Recirculation Valves An automatic recirculation valve (ARV) is a multifunctional valve whose primary purpose is to ensure that a pre-determined minimum flow is assured through a centrifugal pump at all times. This is important as centrifugal pumps suffer from over heating and cavitation and can be permanently damaged if they run dry. uncovered allowing a minimum flow of liquid to be routed back to the pump. One Valve, Many Functions An automatic recirculation valve encompasses all of the hardware required in a conventional bypass system in a single housing. The valve consists of...

Centrifugal Pump Protection Scenarios Centrifugal pumps transform mechanical energy into pressure energy by means of centrifugal force resulting from impeller rotation acting on the fluid within the pump. The pump requires a minimum liquid flow in order to avoid overheating. If a predefined minimum flow is not maintained, the pump can be permanently damaged. A number of different pump protection scenarios are reviewed below. The pump has no back-flow prevention and therefore product will flow back through it once it has stopped. A non return valve (NRV) is therefore usually placed after the...

ARV Operating Conditions 1. Main Flow Only – Bypass Closed When the process associated with the pump is in the normal operating condition, the main line is open. The pressure created from the media flow is sufficient to compress the spring in the check valve disc and lift it from its seat to the fully open position. As the connected disc stem rises, the bypass exit in the stem funnel is moved against the valve body and the bypass system is closed. The recirculation flow is blocked, thus eliminating wasted energy. This is illustrated in figure 1. The bypass flow is therefore inversely...

ARV Product Range SureFlo™ n or 1 to 10 inch pump applications F n ixed letdown in the bypass F n Up to ASME  2500  pressure class # n ariable bypass delay V n ewer moving pieces F n ast housing in CS or SS material C HighFlo™ n or 10 inch+ pump applications F n ixed letdown in the bypass F n etter noise attenuation B n Up to ASME  4500  pressure class # n ariable bypass delay V n orged or cast body F ControlFlo™ n ize independent S n igh pressure design H n ultistage letdown M n nhanced bypass sealing E n etdown varies with stroke L n nhanced noise attenuation E n orged or cast body in CS...

Product Range & Technical Data Product Range Product Range 1 inch (DN 25) to 10 inch (DN 250) pumps and up to ASME 2500# pressure class 10 inch (DN 250) to 16 inch (DN 400) and up to ASME 4500# pressure class for enhanced bypass sealing and multistage letdown to create a defined pressure differential in order to eliminate flashing and cavitation in special applications. Used with an automatic recirculation valve with special maritime body and trim material – size and pressure class as required for special pump applications or unique operating environments and severe media HighFlo™...

Selected ARV Dimensions and Parts List Dimension Table Inlet/Outlet Size Bypass Size Pressure Class ASME 150 ASME 300 ASME 300 ASME 300 ASME 300 ASME 300 ASME 300 ASME 300 ASME 300 The dimension table below is for illustrative purposes for automatic recirculation valves up to eight inches. SchuF can produce automatic recirculation valves in all sizes and pressure classes as required by the application or operating conditions. b= b= SureFlo™ Parts List (High temperature design example) Material Upper body Lower body Disc with spindle Spring guide Bypass body Control bushing Bush Spring guide...

Control Trim and Control Valve Options ARV Control Trim Options Minimum Recirculation Control Valve SchuF offers a variety of automatic recirculation valve control trim options. Choice will depend on many factors such as the medium, the required pressure drop, solid contents and the nature of the process. The most common form of pressure control in the bypass line is achieved via a series of nozzle plates. The required pressure drop is achieved by varying the number, size and position of the nozzles in the bypass and the number of plates used. Despite the diversity of control options...

ARV Applications and Media Automatic recirculation valves have the primary purpose of protecting pumps. They are found in most industries and can be used with a broad variety of pump applications: ARV Applications n eneral centrifugal pumps G n oiler feed water pumps B n ooling plant feed pumps C n rude oil pumps C n luid gas pumps (for LNG, LPG etc.) F n rocess liquid pumps P n ooster pumps B n eawater injection pumps S n ire fighting pumps F SureFlo™ in a boiler feedwater application ARV Media and Industry Examples Industry Temperature Size Chemical plant Chemical plant LNG plant Offshore...

Automatic Recirculation Valve – Data Sheet Please use this data sheet to send your inquiries to us. Items marked in bold print indicate essential information. Part 1 – Company Information Name: Company: E-mail: Part 2 – Order Information General: Quantity: Tag No.: Valve Model: 78PS Automatic Recirculation Valve Application: Project Name: Projekt No: Part 3 – Valve and Process Information Valve Information: Valve Inlet Size (DN/Inch): Valve Outlet Size (DN/Inch): Bypass Outlet Size (DN/Inch): Materials Housing: Installation: Vertical Ȟ or Horizontal Ȟ Process Information: Process: Medium:...

Product Portfolio Overview In over one hundred years, the SchuF Group has delivered more than one million valves to a wide variety of industries in over 50 countries worldwide. Headquartered near Frankfurt in Germany, the company has additional design and manufacturing centres in Italy, India, Ireland, UK and the USA. The SchuF Group has sales and agent offices covering almost every country in the world. We manufacture valve products that control, isolate, divert, and sample liquids, gases, powders, and slurries. Our product range of engineered, customised valves includes: Drain & Sampling...