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US-12618745-B2 - Method for predicting, regulating and controlling wear characteristic of flow channel in valve

US12618745B2US 12618745 B2US12618745 B2US 12618745B2US-12618745-B2

Abstract

A method for predicting, regulating and controlling a wear characteristic of a flow channel in a valve. The method comprises: pasting an aluminum sheet in a valve core, and testing a wear rate; regulating inlet pressure, and obtaining distribution characteristics of a pressure field and a velocity field; establishing an association relationship between the wear rate and pressure and a flow velocity; increasing the inlet pressure, and drawing a discrete data curve and a continuous curve; obtaining a discrete data change curve and a continuous curve of the wear rate along with an opening degree of the valve core; obtaining an association relationship graph between the wear rate of the aluminum sheet and the inlet pressure and the opening degree of the valve core; and performing comparison and determination on a real-time wear rate actual value of the aluminum sheet and a critical wear rate value.

Inventors

  • Haozhe JIN
  • Guofu OU
  • Zuchao Zhu
  • Chao Wang

Assignees

  • ZHEJIANG SCI-TECH UNIVERSITY

Dates

Publication Date
20260505
Application Date
20211227
Priority Date
20210508

Claims (8)

  1. 1 . A method for predicting, regulating and controlling wear characteristic of a flow channel in a valve, the method comprises: 1) Building a circulating pipeline loop, disposing liquid phase oil and particles in the circulating pipeline loop, disposing opposite flanges in a middle region of the circulating pipeline loop, disposing a multi-stage depressurization string type liquid level regulating valve between the opposite flanges, transmitting and pressurizing the liquid phase oil and the particles in the circulating pipeline loop and regulating pressure of an inlet and an outlet of the multi-stage depressurization string type liquid level regulating valve by using a circulating pump and a pressure pump; 2) Defining a number of throttling times of fluid in a fluid domain between a valve core ( 13 ) and a valve sleeve ( 3 ) as a number of stages; 3) During a test, fixing and attaching aluminum sheets at different locations on an inner sidewall of the valve sleeve ( 3 ) and an outer sidewall of the valve core ( 13 ) at each stage in the multi-stage depressurization string type liquid level regulating valve, and attaching n pressure strain gauges and m current meters to a location near each of the aluminum sheet, real time collecting and converting to obtain m flow velocity value distributions and n pressure value distributions at different positions of the inner sidewall of the valve sleeve ( 3 ) and the outer sidewall of the valve core ( 13 ) at different times; after each set of experimental tests is completed, testing a wear rate KE C of the aluminum sheet based on scanning of a laser displacement sensor; 4) Regulating an inlet pressure of the multi-stage depressurization string type liquid level regulating valve to 11.7 MPa, using step 3) to convert the obtained n pressure value distributions and m flow velocity value distributions at different times and locations, obtaining distribution characteristics of a pressure field and a velocity field within the fluid domain; building cross correlation between wear rate KE C , pressure distribution and flow velocity distribution based on wear depth of the aluminum sheet obtained by the scanning of the laser displacement sensor; 5) Sequentially increasing and regulating the inlet pressure P in of the multi-stage depressurization string type liquid level regulating valve at a fixed pressure interval, repeating the experimental method step 4), and respectively drawing a discrete data curve of the wear rates KE C of the aluminum sheets in different stages changing with the inlet pressure P in ; 6) For the discrete data curve of the wear rate KE C of the aluminum sheet changing with the inlet pressure P in , performing data fitting to obtain a continuous curve of the wear rate of the aluminum sheet changing with the inlet pressure; 7) Dynamically regulating and controlling heights of different valve stems, so that the valve core is driven to move up and down, relative to the locations of the valve core sleeve, thereby adjusting opening degree of the multi-stage depressurization string type liquid level regulating valve; under conditions of different opening degrees, testing the wear rate of the aluminum sheet according to change of the opening degrees to obtain a discrete data curve of the wear rate of the aluminum sheet changing with the openness of the valve core, thereby obtaining a continuous curve of the wear rate of the aluminum sheet changing with the openness of the valve core through data fitting; further obtaining association relationship graph of the wear rate of the aluminum sheet, the inlet pressure and the opening degree of the valve core by using the continuous curve of the wear rate of the aluminum sheet changing with the inlet pressure, combined with the continuous curve of the wear rate of the aluminum sheet changing with the opening degree of the valve core; 8) repeating step 7), changing particle size and particle concentration, continuingly to further obtain association relationship graph of the wear rate of the aluminum sheet, the inlet pressure, the opening degree of the valve core, particle size and particle concentration; 9) during a dynamically regulating process, pre-setting a critical wear rate [ε] based on a wear resistant characteristic and a wear setting allowance of the aluminum sheet, and comparing based on real time dynamic wear rate actual value KE C of aluminum sheet and the critical wear rate [ε]: if KE C <0.95[ε], then the valve stem location, the inlet pressure and the opening degree of the valve core remain unchanged; if KE C ≥0.95[ε], then the opening degree of the valve core, the inlet pressure, the particle size and the particle concentration are regulated, and dynamically update the real time wear rate actual value KE C of the aluminum sheet until KE C <0.95[ε], so as to avoid rapid wear and failure of the valve core.
  2. 2 . The method for predicting, regulating and controlling wear characteristic of the flow channel in the valve as claimed in claim 1 , wherein the valve is a multi-stage depressurization string type liquid level regulating valve structure, specifically comprising a valve body ( 1 ), a valve base ( 2 ), a valve sleeve ( 3 ), a valve cap ( 12 ) and a valve core ( 13 ); a vertical cavity is disposed in the valve body ( 1 ), a valve base ( 2 ) is disposed in the vertical cavity, the valve base ( 2 ) divides the vertical cavity into a throttling valve core cylindrical cavity located at an upper part and a buffer cylindrical cavity located at a lower part, the valve base ( 2 ) is configured with a center through hole, which connects the throttling valve core cylindrical cavity and the buffer cylindrical cavity, an inlet and an outlet are disposed on two sides of the valve body ( 1 ) respectively, the inlet is connected to a bottom of the buffer cylindrical cavity, the outlet is connected to a bottom of the throttling valve core cylindrical cavity; the valve sleeve ( 3 ) is fixedly disposed in the throttling valve core cylindrical cavity, an annular gap is between an outer sidewall of the valve sleeve ( 3 ) and a wall of the throttling valve core cylindrical cavity, the annular gap is connected to the outlet of the valve body ( 1 ); a bottom of the valve sleeve ( 3 ) is connected to the valve base ( 2 ), the valve core ( 13 ) with a plurality of notches is coaxially disposed in a cavity of the valve sleeve ( 3 ), a flow channel is disposed between the valve core ( 13 ) and the valve sleeve ( 3 ) to form a multi-stage string type pressure reducing structure; a valve cap ( 12 ) is fixedly disposed in an upper port of the valve body ( 1 ), a center hole coaxially connected with the throttling valve core cylindrical cavity is disposed in the center of the valve cap ( 12 ), an end surface around the center hole of the valve cap ( 12 ) axially presses the valve sleeve ( 3 ) against the valve base ( 2 ); a plurality of through holes evenly disposed on the upper sidewall, along a circumferential direction, of the valve sleeve ( 3 ) away from the valve base ( 2 ), a fluid medium flows from the inlet of the valve body ( 1 ) into the buffer cylindrical cavity, passes through the center through hole of the valve base ( 2 ) and then flows into the throttling valve core cylindrical cavity, the fluid medium after throttling and decompression in the throttling valve core cylindrical cavity flows out from the evenly disposed through holes on the upper sidewall of valve sleeve ( 3 ) into the annular gap between the valve body ( 1 ) and the valve sleeve ( 3 ), and confluences to the outlet of the valve body ( 1 ) through the annular gap.
  3. 3 . The method for predicting, regulating and controlling wear characteristic of the flow channel in the valve as claimed in claim 2 , wherein a valve stem ( 9 ) is disposed in the center hole of the valve cap ( 12 ), and an upper end of the valve core ( 13 ) passes through the center hole of the valve cap ( 12 ) and then is fixedly connected to a lower end of the valve stem ( 9 ).
  4. 4 . The method for predicting, regulating and controlling wear characteristic of the flow channel in the valve as claimed in claim 3 , wherein the annular gap between the valve stem ( 9 ) and the center hole of the valve cap ( 12 ) is configured, from bottom to top, with a packing mat ( 6 ), a packing ( 7 ), and a packing gland ( 10 ), an upper end of the packing gland ( 10 ) protruding from the center hole of the valve cap ( 12 ) is configured with an outer flange, a flange ( 16 ) is disposed over the packing gland ( 10 ), the flange ( 16 ) is fixedly connected to an upper part of the valve cap through a screw ( 8 ), and the flange ( 16 ) is pressed against the packing gland ( 10 ) through the screw ( 8 ).
  5. 5 . The method of predicting and controlling valve internal channel wear characteristic as claimed in claim 3 , wherein a connecting sheath ( 11 ) is coaxially connected between the lower end of the valve stem ( 9 ) and the upper end of the valve core ( 13 ), and the valve stem ( 9 ) drives the valve core ( 13 ) to move axially up and down within the valve sleeve ( 3 ).
  6. 6 . The method of predicting and controlling valve internal channel wear characteristic as claimed in claim 2 , wherein a guide sleeve ( 4 ) is sleeved outside the valve core ( 13 ) at a joint of the valve cover ( 12 ) and the valve core sleeve ( 3 ).
  7. 7 . The method for predicting, regulating and controlling wear characteristic of the flow channel in the valve as claimed in claim 2 , wherein the multi-stage string type pressure reducing structure between the valve core ( 13 ) and the valve sleeve ( 3 ) comprises: a stepped cavity disposed in the valve sleeve ( 3 ) located below the through hole at the upper end of the valve sleeve ( 3 ), a plurality of inner flanges, serving as throttling rings, spaced apart axially in the stepped cavity from top to bottom, and the stepped cavity is divided into a plurality of small cavities by the throttling rings; the valve core ( 13 ) in the valve core sleeve ( 3 ) is characterized in that a plurality of symmetrical groove structures are axially disposed from top to bottom, each of the symmetrical groove structures comprises two grooves respectively and symmetrically arranged at two sides of the valve core ( 13 ) along a symmetrical direction, and the symmetrical directions of the two grooves of two adjacent symmetrical groove structures are vertical to each other; an inner diameter of the throttle ring is consistent with an outer diameter of the valve core ( 13 ), and a width of the groove is larger than a thickness of the throttle ring.
  8. 8 . The method for predicting, regulating and controlling wear characteristic of the flow channel in the valve as claimed in claim 2 , wherein annular grooves are disposed on an upper end surface and a lower end surface of the valve base ( 2 ), and the annular grooves are all configured with a flange spiral wound gasket ( 15 ) therein for sealing.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application is a 371 of international application of PCT application serial no. PCT/CN2021/141434, filed on Dec. 27, 2021, which claims the priority benefit of China application no. 202110499991.2, filed on May 8, 2021. The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of this specification. BACKGROUND Technical Field The present disclosure relates to the technology of regulating valve performance in the process industry, and in particular to a method of predicting, regulating and controlling wear characteristic of flow channel in a multi-stage depressurization string type liquid level regulating valve. Description of Related Art Energy resources in China present the current situation of “more coal, lack of oil and less gas”, so the development of the modern coal chemical industry is an important measure for ensuring the safety of national energy strategy and ensuring that China reaches the development level of moderately developed countries in the middle of the century. The liquid level regulating valve is a key device in the major process industry, a complex flowing state exists in the regulation and control process, the fault rate thereof is high in the actual operation process, and prediction, prevention and control of the fault are difficult. For example, the wear failure of a high differential pressure regulating valve in the operation of a world first megaton coal liquefaction demonstration project is very serious. Despite the adoption of the high-end product of SchuF, company of Germany, and the addition of more than 2 hundred million investments to design a single channel as four parallel, the service life of the actual single valve is still short. The abrasion failure of the liquid level regulating valve seriously restricts the production safety and economic benefit of the coal chemical industry device and the popularization of national demonstration engineering. The wear failure process of the high temperature high differential pressure hydraulic control valve is closely related to factors such as a valve body structure, the physical properties of multi-component fluid, the structural characteristics of a fluid domain, material performance, the characteristics of particles and the like, the research on gas-liquid phase change, energy transfer and material response under the transient condition of the liquid level regulating valve is extremely complex, and the development of related theoretical modeling and experimental research is extremely complex. For a high temperature and high differential pressure hydraulic control regulating valve, if the wear characteristics of an internal flow channel of the high temperature and high differential pressure hydraulic control regulating valve cannot be accurately grasped, and a corresponding quantitative wear characteristic prediction method is established, the dynamic regulation and control of the flow wear characteristics of the liquid level regulating valve based on the flow wear characteristic prediction are difficult to realize. The structure optimization design of the high temperature and high differential pressure hydraulic control regulating valve is one of key ways for improving the wear resistance of the high temperature high differential pressure liquid level regulating valve, and although the angle valve structure of the liquid level regulating valve is adjusted to be a multi-stage depressurization string type regulating valve, the throttling capacity of the regulating valve can be effectively improved, higher requirements are provided for the wear resistance between a valve core and a valve sleeve, even between the valve core and a valve base. The existing research results carry out more researches on the internal cavitation and cavitation erosion characteristics of the high differential pressure hydraulic control valve, and also clearly illustrate that the cavitation and cavitation erosion characteristics in the calculation domain of the regulating valve are closely related to the pressure difference between an inlet and an outlet, the cavitation number, the cavitation intensity and the like. In addition, for a coal chemical industry system, particularly a direct coal liquefaction system, the whole process from raw material preparation and reaction separation to residue treatment relates to multiphase flow transmission of pulverized coal solid particles, and the throttling process of the high temperature high differential pressure hydraulic control valve also has a serious flow wear problem. In summary, in the face of the problem of failure of the high differential pressure hydraulic control regulating valve in a complex flowing and corrosive environment, the internal flow channel of the high differential pressure hydraulic control valve is subjected to a multi-stage depressurization string type design according to the internal f