Horizontal centrifugal pump assembly preheating how warm the pump -

when the medium is higher than 200 ℃ when the horizontal centrifugal pump, the pump must be preheated before launch. Otherwise, enter the pump medium will result in higher temperature moment of pump, rapid expansion of rotor, stationary parts are relatively slow heating, the gap between the cause and the static and dynamic components parts is reduced, which may lead to touch each other, friction or blocked. In serious cases, the rotor dynamic balance accuracy is impaired, the rotor may be stuck, it is often referred to as shaft lock. Curing medium, it should be warm pump, otherwise the import and export pipeline easy to curing medium jam, resulting in cavitation and vibration fault.

preheating method and the matters needing attention of horizontal centrifugal pump

1. Heat pump

( 1) When warm water pump unit startup or startup after maintenance, the pump is warm mode should be adopted, namely the pump suction valve slightly open, medium from the pump inlet flows through the pump body, and from the pump discharge pipe discharge valve to the specified collection device. It can also be called intermittent warming pump.

( 2) Note start heat pump and the cautions of heat pump is as follows:

1) Warm heat pump speed is 15 30 ℃ / hour

2) When the difference between the pump body temperature and medium temperature 20 ℃ or less, can complete the preheating of the pump.

3) Are after the warm, close to warm the pump discharge valve, and start again after meet other driving conditions.

2。 The standby pump

( 1) OH2 structure warm standby pump pump makes a small amount of material from the pump discharge pipe through operating, through the spare pump in the pump body, and then return to the pump inlet, the standby pump in hot standby state, prevent medium in standby pumps and suction and discharge pipe solidification, effectively maintain warm pump, easy to start, need to reverse heating. That is to say, warm behind the cut-off valve of the pump pipe line from the water pump discharge pipeline are guided to export in the front of the check valve. Gate valves and orifice is set in warm owing to the road, so a small amount of material from the warm pump pipe road through the main pump, slowly through the spare pump pump body, and returns the pump suction, achieve the goal of continuous warm pumps.

( 2) BB2 structure BB2 warm standby pump pump pump structure, the warm standby pump method from the pump discharge cut-off valve line back to the warm parallel to the pump outlet pipe of pump pipe road, slow medium flow back to water pump suction, warm pump pipe road equipped with gate valves and orifice.

( 3) Note the warm standby pump pump considerations are as follows:

1) Warm the pump flow should not be too big, for 3% ~ 5% rated flow as far as possible, in order to effectively keep the standby pump will not reverse.

2) The standby pump starts, must close valve.

3) Warm pump heating rate 20 ℃ / hour or less

4) body temperature 35 ℃ or less.

5) When the pump body upper and medium temperature 25 ℃ or less, the standby pump can be started.

6) Every half hour, in the whole process of warm pump rotation a spare pump, rotor rotate for 180 degrees halt. If the rotation is difficult, stop running, waiting for the temperature continues to rise after a period of time to continue.

7) According to the size of the pump outlet pressure, calculate according to the characteristics of the medium and choose the appropriate orifice plate, such as single stage orifice plate can't meet the requirements should be choose multi-stage orifice, prevent cavitation cavitation phenomenon.

8) When running switch to the standby pump, also should adjust the appeal procedure, until it is in a state to restart.

3。 Other

if the temperature is below the freezing point of material, also should be set to warm the pump bypass, in order to prevent the material inside the pump set. In addition, the pump should be set up between entry and exit the condensing bypass. It should be from the pump discharge valve is connected to the pump inlet valve. Maintenance spare pump, the standby pump suction should be closed and export cut-off valve, and open the condensate line valve. A small amount of liquid should be slow flow in the pump suction pipe section, in order to effectively keep no condensation of flow in the pipeline.

the recommended reading: 'the application of the vacuum system in medical system'