Increase the heat load when the evaporator in system of industrial water chiller evaporator, refrigerant evaporation increased, to make the evaporation pressure remained unchanged, requires opening increasing back pressure valve, which is generated in the evaporator vapor phase equilibrium and vapor outflow back pressure valve, but this is only the evaporation pressure from Po in order to achieve up to po. At this time, the steam flow rate through the back pressure valve although increased, but because of the opening of the valve increases, so the refrigerant vapor through the back pressure valve of the pressure drop, the back pressure valve import and export pressure difference at both ends of P decreased. When the heat load continues to rise, the back pressure valve all full open, wide steam pressure drop through the minimum rated flow through the refrigerant vapor flow back pressure valve for valve. Obviously, under different evaporation pressure Po and before and after the pressure difference Ap, the valve flow is different. For convenient selection, product specification quantity per hour through the commonly used refrigerant and refrigerant in the evaporator under the pressure of the unit cooling capacity, cooling capacity is in the valve foot when the evaporator to indicate the capacity of each valve.
      Back pressure valve from fully open to fully closed when the valve before the pressure (evaporation pressure) changes in the magnitude of Ap and the width of the type and adjust the degree of adjustment of the spring; the pre tension of the spring set the greater the magnitude of this change is also greater.
      Back pressure valve is adjusted to meet the requirements of the lower limit, the back pressure valve should be closed in principle. To this end, the adjustment should be in the back pressure valve inlet pressure gauge connector fitted with a pressure gauge, and the pressure gauge valve open. If adjusted properly at low temperature to maintain when the back pressure valve closed, pressure gauge should be stable; if the pressure gauge pressure continues to drop, the back pressure valve is not closed, the evaporator on cooling, the temperature will drop further, so should the clockwise rotation adjustment screw, adjust the spring tension increases, to the valve closed.          At this point, the stability of the pressure gauge pressure is the evaporator evaporation pressure, and the evaporation pressure corresponding to the evaporation temperature and temperature difference between 5 ~ 10 C.
       For more information please contact us: Mr. Wang 13923464030 Tel: 0755-81715045 or visit our website: http://www.szdxj.com