INTRODUCTION
ZDM Series Automatic Recycle Valve (ARC valve) is a kind of pump protection device. It automatic protect centrifugal pump when pump body occur cavitation damage or unstable (especially conveying hot water at low load operation medium). Once pump flow is lower than the preseted flow, bypass can completely open to ensure the minimum required flow pump. Even running fully closed, namely running flow is zero, the minimum flow can also pass bypass for Automatic Recycle. Pressure reduced through the multistage bypass pressure reducing valve.
ZDM series Automatic Recycle Valve is suitable for bypass with high pressure differential, maximum pressure differential is 30MPa, and specific choice is determined by factory. Multistage decompression type M type bypass can eliminate noise made by high-speed flow medium, prevent damage of cavitation erosion and braising to valve components.
CHARACTERISTIC
Prevent cavitation multistage decompression bypass, reducing velocity, suitable for high pressure conditions
Forgde valve body, or you can choose carbon steel or stainless steel material, etc.
Standard bypass non-return function, maximum working pressure differential is 30MPa.
Pressure grade from PN16 to PN420, diameter from DN2to DN500.
Can select manual bypass operation function, used in fault.
SIZE AND PRESSURE RANGE
Body type: Three-way forged valve
Nominal diameter: DN25, 32, 40, 50, 65, 80,100, 200, 250, 300, 350, 400, 450, 500
Nominal pressure: PN 16,25,40,64,100,160,250,420 CLASS 150, 300, 600, 900, 1500, 2500LB
End connection: Flange, FF, RF, RTJ, BW, SW etc.
MATERIAL TEMPERATURE RANGE
Body Material
Sealing Materuial A105 LF2 F304 F316
NBR -20～+100 -30～+100 -30～+100 -30～+100
FKM -20～+200 -40～+200 -40～+200 -40～+200
PTFE -20～+230 -40～+230 -80～+230 -80～+230
Stainless steel gasket -20～+300 -40～+300 -196～+300 -196～+300
WORKING PRINCIPLE
According to the difference of inductive main flow, main valve disc check cone of automatic recirculation valve will automatically move to a certain position. At the same time the main valve disc drive bypass valve stem, transfer the movement of main valve disc to bypass, through control bypass valve disc position, change bypass throttling area, so as to control bypass flow. When main valve disc back into valve seat closed, all flow backflow through bypass. When mian valve disc to rise to top position, bypass is fully closed, all the flow of pump flow to process system. This valve set four functions in one body.
Flow perception: automatic recirculation valve main valve disc can automatically perceive main flow of process system, thereby according to the flow to determine position of mian valve disc and bypass disc.
Recirculation control: automatic recirculation valve can inhaled pump normal operation required minimum flow into storage device through bypass, so as to adjust pump H – Q characteristics, to realize recycling.
Bypass multistage pressure reducing: bypass control system can reduc
