Online monitoring device and online monitoring method for thrust bearing wear loss of fully-sealed pump

Abstract

The invention discloses an online monitoring device and an online monitoring method for thrust bearing wear loss of a fully-sealed pump. The online monitoring device comprises a rotor, a thrust disc and a graphite bearing bush of the sealed pump, a hole is formed in the sealed pump and faces towards an end face of the rotor or faces towards a lateral side of the thrust disc, a position probe is mounted in the hole and connected with an inductive transducer, the inductive transducer is connected with an amplifier via a signal transmission line, the amplifier is connected with an analog / digital converter via the signal transmission line, and the analog / digital converter is connected with a computer via the signal transmission line. The online monitoring device and the online monitoring method have the advantages that different mounting manners can be selected according to different mounting positions, and moving distance of the thrust disc can be reflected directly and accurately by both measuring methods, so that moving amount of the graphite bearing bush can be obtained, wear conditions of a water-lubricated thrust bearing inside the fully-sealed pump can be reflected directly, and faults like sudden shutdown can be avoided.

Description

technical field [0001] The invention relates to a fully-sealed pump monitoring device for a reactor system, in particular to an on-line monitoring device and method for the wear amount of a thrust bearing of a fully-sealed pump. Background technique [0002] The vertically arranged hermetic pumps (including shielded pumps, wet stator pumps, etc.) used in nuclear power plant reactors have the advantages of simple structure and zero leakage. They are mainly used for the main pump and auxiliary pump of the primary circuit system of the reactor. It is all covered in the pressure boundary of the primary circuit medium, and it is not easy to monitor the operating conditions of the rotating parts including the bearing. In order to ensure the safe and reliable operation of the fully sealed pump during its service life, it is necessary to wear the friction pair of the water-lubricated thrust bearing Real-time monitoring of the status to avoid excessive wear of the thrust bearings lea...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide an online monitoring device and method for thrust bearing wear of a fully sealed pump, overcome the problem of low measurement accuracy in the current monitoring method, and achieve the purpose of accurately measuring graphite bearing bush wear

In actual use, the applicant found that there are problems in the two current methods of measuring the wear of graphite bearing pads: in the method of determining the amount of wear by changing the water temperature, since there are many factors that cause the change of the water temperature, the change of the water temperature is used to determine the amount of wear. There are uncertain factors in the way of reaction wear, and the sensor embedded in the graphite bearing pad of the thrust bearing can only measure the change of the thickness of the water film formed between the thrust plate and the graphite bearing pad of the bearing when the bearing is running at a stable speed, and cannot monitor the thrust bearing bearing. The amount of wear of the graphite bearing bush itself, in view of these problems, the applicant has obtained a technical solution to solve these problems through theoretical research and experiments: the present invention is provided with an opening on the sealed pump, and a position probe is set in the opening, through the position probe, The sensor is used to directly measure the position change of the thrust plate, and the measured wear amount can be judged more directly and accurately. Since the friction pair of the water-lubricated thrust bearing is composed of a disc-shaped thrust plate with a slightly higher hardness and an annular ring with a slightly lower hardness Arranged graphite bearing pads are paired together. The thrust disc is usually formed by surfacing welding hard wear-resistant alloy. The thrust disc and the rotor adopt a rigid fixed connection structure. Graphite bearing pads are usually worn out parts that need to be replaced in a timely manner; When the sealed pump is running, the thrust disc and the rotor are continuous rotating parts around the axis, and the graphite bearing pad is a stationary part. Since the axial load of the thrust bearing acts on the graphite bearing pad through the thrust disc and keeps downward, the thrust disc in the friction pair of the bearing will last for a long time. The running of graphite bearing pads with lower hardness will cause the wear rate of the graphite bearing pads in contact with it to be much faster than that of the thrust disc. Sinking, that is to say, the wear amount of the thrust bearing pad will be consistent with the sinking displacement of the thrust disc and rotor. Therefore, real-time online displacement monitoring of the displacement of the thrust disc or rotor can measure the water-lubricated thrust bearing. amount of wear and wear condition

Images