SU861732A1 - Method of detecting cavitation in blade-type pump - Google Patents

Description

one

The invention relates to the field of

There is a known method of detecting cavitation in a vane pump by determining the characteristics that change upon the occurrence of cavitation, in cavitation-free and cavitation modes of operation, and then comparing the characteristics obtained 1.

The known method does not provide accurate detection of cavitation in the initial stage.

To increase accuracy, the trajectory of the process movement of the pump shaft is used as a characteristic.

The drawing shows a diagram of the device that implements the described method.

The device comprises a rotor 1 of a blade pump, displacement sensors 2 mounted at an angle of 90 ° to each other, connected through an amplifying device 3 to a loop oscillograph 4, a magnetic recorder 5 and an electron-beam oscilloscope 6.

The method of detecting cavitation in a paddle pump consists in determining the characteristics, changes in the event of cavitation, on beskazitatsionnym and cavitational modes of operation and subsequent comparison of the characteristics obtained, while using the trajectory of the precessional motion of the entire pump as a characteristic.

A device that implements the described method works as follows.

When the gaps between the ends of the sensors 2 and the surface of the rotor 1 change, due to the precessional movement of the rotor 1, the values of the electrical signals of the sensors 2 change. recorder 5 for signal analysis. In order to visualize the movement of the rotor 1, a known circular scanning method can be applied. In this case, the signals from the sensors 2 podgiots on

25 electron beam oscilloscope b, on the screen of which you can directly see the trajectory of the precessional motion of the rotor 1.; If.in the work of the coca under study, a decrease in pressure in the

when entering the pump is accompanied by a change in the trajectory and precessional motion of the rotor compared with the trajectory obtained at the same value of the angular velocity of the rotor in the non-cavitational rechlah pump operation, this indicates the appearance of cavitation formations in the pump.

Claims (1)

Invention Formula Method o} on; of cavitation cavitation in the blade (pump by determining characteristics that change upon the occurrence of cavitation during cavitation and cavitation modes of operation and subsequent comparison of the characteristics obtained, characterized in that, in order to increase accuracy, the trajectory of the precessional movement of the pump shaft is used as a characteristic. Sources of INFORMATION, taken into account during the examination 1. Knapp R., Daily J., Hammit F. Kavitatsi - M.j Mir, 1974, p.33-34.