A quantitative judgment method for the load-bearing state of variable-force spring hangers

Abstract

The present invention discloses a quantitative judgment method for the load-bearing state of a variable-force spring hanger, which belongs to the inspection and detection category of pipeline hangers and can be widely used in the fields of electricity and energy. The method makes full use of the factory performance test data of the variable-force spring hanger products, and accurately judges the load-bearing state of each group of spring hangers by combining the actual height of the springs measured on site, and can quantitatively distinguish the load-bearing states of different groups of spring hangers. This provides a theoretical basis for on-site technicians to scientifically and normatively describe the load-bearing state of variable-force spring hangers when carrying out status inspections of steam and water pipeline hangers in thermal power plants, and provides strong data support for technicians to formulate adjustment and processing plans for pipeline hangers based on cold and hot state inspection results, which helps to promote the standardization and standardization of steam and water pipeline hanger inspections in thermal power plants.

Description

Technical Field

[0001] The present invention relates to a quantitative judgment method for the load-bearing state of a variable-force spring support and hanger, belongs to the inspection and detection category of pipeline supports and hangers, and can be widely used in the fields of electricity and energy. Background Art

[0002] Currently, relevant standards for variable-force spring supports and hangers, both domestically and internationally, lack a scientific and standardized description of their load-bearing status. Common standards include "Variable Spring Supports and Hangers" (NB / T 47039-2013), "Guidelines for Maintenance and Adjustment of Steam-Water Pipelines and Supports and Hangers in Thermal Power Plants" (DL / T 616-2006), and "Acceptance Procedures for Pipe Supports and Hangers in Thermal Power Plants" (DL / T1113-2009). During inspections of steam-water pipe supports and hangers in thermal power plants, due to a lack of quantitative criteria and standardized descriptive language, technicians are often forced to use vague terms such as "cold position," "slightly above cold position," "slightly below cold position," "slightly above cold position," and "slightly below cold position" to describe the load-bearing status of spring hangers. This makes it difficult to quantify the load-bearing status of spring hangers at different installation positions, making it difficult for subsequent technicians to formulate adjustment plans for pipe supports and hangers based on the results of cold and hot inspections. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art and to provide a scientific, reasonable and operable method for accurately judging the load-bearing state of a variable force spring hanger.

[0004] The technical solution adopted by the present invention to solve the above problem is: a method for quantitatively judging the load state of a variable force spring hanger, characterized by comprising the following steps:

[0005] Step 1: Slowly and uniformly load the variable force spring hanger, and measure the load values at the minimum scale line and the maximum scale line of the displacement indicator plate. Divide the difference between the two load values by the corresponding displacement to obtain the actual spring stiffness value K. s ;

[0006] Step 2: Load the variable force spring hanger so that the lower edge of the displacement indicator plate is aligned with the installation position scale line on the nameplate, and measure the actual installation load value W s , the actual installation load value W s With the standard installation load value W b The absolute value of the difference is recorded as ΔW;

[0007] Step 3: Use the actual installation load value W s With the standard installation load value W b The relative deviation ΔW is divided by the actual stiffness value K s, get the allowable displacement deviation ΔL;

[0008] Step 4: Measure the height of the variable force spring hanger spring on site, and record the measured data as H s At the same time, measure the spring height corresponding to the cold mark line and the spring height corresponding to the hot mark line, and record them as H c and H t ;

[0009] Step 5: Based on the relative positions of the displacement indicator plate and the cold and hot identification lines on the nameplate, accurately judge and record the load-bearing status of the variable force spring hanger.

[0010] Furthermore, the actual installation load value W s With the standard installation load value W b This can usually be checked in the product quality certificate of the spring hanger.

[0011] Furthermore, in practical applications, pipeline thermal displacement occurs in two directions: vertically upward and vertically downward. The determination of the load-bearing state of the variable force spring hanger requires setting criteria according to the different directions of the pipeline thermal displacement.

[0012] Furthermore, the measured installation load value W s With the standard installation load value W b The size relationship is directly related to the judgment of the load-bearing state of the variable force spring hanger and should be discussed in categories.

[0013] Furthermore, when the thermal displacement of the pipeline is downward, there are two situations:

[0014] Case 1: When W b Greater than W s hour:

[0015] (1) When H s Satisfy condition H t <H s <H c When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t );

[0016] (2) When H s Satisfy the condition H-ΔL≤H s ≤H t When , the load-bearing state of the spring hanger is recorded as "normal";

[0017] (3) When H s Satisfy condition H s <H t-ΔL, the load state of the spring hanger is recorded as "overload", and the overload value W g =K s ·(H t -ΔL-H s ).

[0018] Case 2: When W b Less than W s hour:

[0019] (1) When H s Satisfy condition H t +ΔL<H s <H c When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t -ΔL);

[0020] (2) When H s Satisfy condition H t ≤H s ≤H t When +ΔL, the load-bearing state of the spring hanger is recorded as “normal”;

[0021] (3) When H s Satisfy condition H s <H t When the spring hanger is loaded, the load state is recorded as "overload", and the overload value W g =K s ·(H t -H s ).

[0022] Furthermore, when the thermal displacement of the pipeline is upward, there are two situations:

[0023] Case 1: When W b Greater than W s hour:

[0024] (1) When H s Satisfy condition H c <H s <H t -ΔL, the load state of the spring hanger is recorded as "overload", and the overload value W g =K s ·(H-ΔL-H s );

[0025] (2) When H s Satisfy condition H t -ΔL≤H s ≤H tWhen , the load-bearing state of the spring hanger is recorded as "normal";

[0026] (3) When H s Satisfy condition H s >H t When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t ).

[0027] Case 2: When W b Less than W s hour:

[0028] (1) When H s Satisfy condition H c <H s <H t When the spring hanger is loaded, the load state is recorded as "overload", and the overload value W g =K s ·(H t -H s );

[0029] (2) When H s Satisfy condition H t ≤H s ≤H t When +ΔL, the load-bearing state of the spring hanger is recorded as “normal”;

[0030] (3) When H s Satisfy condition H s >H t +ΔL, the load state of the spring hanger is recorded as "underload", and the underload value W c =K s ·(H s -H t -ΔL).

[0031] Compared with the prior art, the present invention has the following advantages and effects: the method makes full use of the factory performance test data of the variable force spring support hanger products, and accurately judges the load-bearing state of each group of spring supports and hangers by combining the actual height of the springs measured on site, and can quantitatively distinguish the load-bearing states of different groups of spring supports and hangers. It provides a theoretical basis for on-site technicians to scientifically and normatively describe the load-bearing state of the variable force spring supports and hangers when carrying out the status inspection of the steam and water pipeline supports and hangers in thermal power plants, and provides strong data support for technicians to formulate adjustment and processing plans for pipeline supports and hangers based on the cold and hot inspection results, which helps to promote the standardization and standardization of the inspection work of steam and water pipeline supports and hangers in thermal power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The thermal displacement of the pipeline in the present invention is downward and W b >W s Schematic diagram of the load-bearing condition of the time-varying force spring hanger.

[0033] Figure 2 The thermal displacement of the pipeline in the present invention is downward and W b >W s Schematic diagram of the load-bearing condition of the time-varying force spring hanger.

[0034] Figure 3 The thermal displacement of the pipeline in the present invention is upward and W b >W s Schematic diagram of the load-bearing condition of the time-varying force spring hanger.

[0035] Figure 4 The thermal displacement of the pipeline in the present invention is upward and W b >W s Schematic diagram of the load-bearing condition of the time-varying force spring hanger. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and through examples. The following examples are intended to explain the present invention but the present invention is not limited to the following examples.

[0037] Example

[0038] See also Figures 1 to 4 In this embodiment, the quantitative determination method of the load-bearing state of the variable force spring hanger includes the following steps:

[0039] Step 1: Slowly and uniformly load the variable force spring hanger, and measure the load values at the minimum scale line and the maximum scale line of the displacement indicator plate. Divide the difference between the two load values by the corresponding displacement to obtain the actual spring stiffness value K. s ;

[0040] Step 2: Load the variable force spring hanger so that the lower edge of the displacement indicator plate is aligned with the installation position scale line on the nameplate, and measure the actual installation load value W s , the actual installation load value W s With the standard installation load value W b The absolute value of the difference is recorded as ΔW;

[0041] Step 3: Use the actual installation load value W s With the standard installation load value W b The relative deviation ΔW is divided by the actual stiffness value K s , get the allowable displacement deviation ΔL;

[0042] Step 4: Measure the height of the variable force spring hanger spring on site, and record the measured data as H s At the same time, measure the spring height corresponding to the cold mark line and the spring height corresponding to the hot mark line, and record them as H c and H t ;

[0043] Step 5: Based on the relative positions of the displacement indicator plate and the cold and hot identification lines on the nameplate, accurately judge and record the load-bearing status of the variable force spring hanger.

[0044] In this embodiment, the actual installation load value W s With the standard installation load value W b Check the product quality certificate of the spring hanger. In actual application, the thermal displacement of the pipeline exists in two directions: vertically upward and vertically downward. The load state of the variable force spring hanger is judged according to the different directions of the thermal displacement of the pipeline. The measured installation load value W s With the standard installation load value W b The size relationship is directly related to the judgment of the load-bearing state of the variable force spring support hanger, and is discussed in categories below.

[0045] When the thermal displacement of the pipe is downward, there are two situations:

[0046] Case 1: When W b Greater than W s hour:

[0047] (1) When H s Satisfy condition H t <H s <H c When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t );

[0048] (2) When H s Satisfy the condition H-ΔL≤H s ≤H t When , the load-bearing state of the spring hanger is recorded as "normal";

[0049] (3) When H s Satisfy condition H s <H t -ΔL, the load state of the spring hanger is recorded as "overload", and the overload value W g =K s ·(H t -ΔL-H s ).

[0050] Case 2: When W b Less than W s hour:

[0051] (1) When H s Satisfy condition H t +ΔL<H s <H c When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t -ΔL);

[0052] (2) When H s Satisfy condition H t ≤H s ≤H t When +ΔL, the load-bearing state of the spring hanger is recorded as “normal”;

[0053] (3) When H s Satisfy condition H s <H t When the spring hanger is loaded, the load state is recorded as "overload", and the overload value W g =K s ·(H t -H s ).

[0054] When the thermal displacement of the pipe is upward, there are two situations:

[0055] Case 1: When W b Greater than W s hour:

[0056] (1) When H s Satisfy condition H c <H s <H t -ΔL, the load state of the spring hanger is recorded as "overload", and the overload value W g =K s ·(H-ΔL-H s );

[0057] (2) When H s Satisfy condition H t -ΔL≤H s ≤H t When , the load-bearing state of the spring hanger is recorded as "normal";

[0058] (3) When H s Satisfy condition H s >H t When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value Wc =K s ·(H s -H t ).

[0059] Case 2: When W b Less than W s hour:

[0060] (1) When H s Satisfy condition H c <H s <H t When the spring hanger is loaded, the load state is recorded as "overload", and the overload value W g =K s ·(H t -H s );

[0061] (2) When H s Satisfy condition H t ≤H s ≤H t When +ΔL, the load-bearing state of the spring hanger is recorded as “normal”;

[0062] (3) When H s Satisfy condition H s >H t +ΔL, the load state of the spring hanger is recorded as "underload", and the underload value W c =K s ·(H s -H t -ΔL).

[0063] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0064] Although the present invention has been disclosed above with reference to the embodiments, it is not intended to limit the scope of protection of the present invention. Any changes and modifications made by any technician familiar with the technology without departing from the concept and scope of the present invention should fall within the scope of protection of the present invention.

Claims

1. A quantitative determination method for the load-bearing state of a variable force spring hanger, characterized in that: The following steps are involved: Step 1: Slowly and uniformly load the variable force spring hanger, and measure the load values at the minimum scale line and the maximum scale line of the displacement indicator plate. Divide the difference between the two load values by the corresponding displacement to obtain the actual spring stiffness value K. s ; Step 2: Load the variable force spring hanger so that the lower edge of the displacement indicator plate is aligned with the installation position scale line on the nameplate, and measure the actual installation load value W s , the actual installation load value W s With the standard installation load value W b The absolute value of the difference is recorded as ΔW; Step 3: Use the actual installation load value W s With the standard installation load value W b The relative deviation ΔW is divided by the actual stiffness value K s , get the allowable displacement deviation ΔL; Step 4: Measure the height of the variable force spring hanger spring on site, and record the measured data as H s At the same time, measure the spring height corresponding to the cold mark line and the spring height corresponding to the hot mark line, and record them as H c and H t ; Step 5: Based on the relative positions of the displacement indicator plate and the cold and hot identification lines on the nameplate, accurately judge and record the load-bearing status of the variable force spring hanger.

2. The quantitative determination method of the load-bearing state of the variable force spring hanger according to claim 1, characterized in that: Actual installation load value W s and standard installation load value W b Check in the product quality certificate of the spring hanger.

3. The quantitative determination method of the load-bearing state of the variable force spring hanger according to claim 1, characterized in that: In practical applications, pipeline thermal displacement occurs in two directions: vertically upward and vertically downward. The load-bearing state of the variable force spring hanger is determined by setting criteria according to the different directions of pipeline thermal displacement.

4. The quantitative determination method of the load-bearing state of the variable force spring hanger according to claim 3, characterized in that: Measured installation load value W s With the standard installation load value W b The size relationship is directly related to the judgment of the load-bearing state of the variable force spring hanger. The judgment of the load-bearing state of the variable force spring hanger is based on the measured installation load value W. s With the standard installation load value W b The sizes are classified and discussed.

5. The quantitative determination method of the load-bearing state of a variable force spring hanger according to any one of claims 1 to 4, characterized in that: The process is as follows: When the thermal displacement of the pipe is downward, there are two situations: Case 1: When W b Greater than W s hour: (1) When H s Satisfy condition H t <H s <H c When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t ); (2) When H s Satisfy the condition H-ΔL≤H s ≤H t When , the load-bearing state of the spring hanger is recorded as "normal"; (3) When H s Satisfy condition H s <H t -ΔL, the load state of the spring hanger is recorded as "overload", and the overload value is W g =K s ·(H t -ΔL-H s ); Case 2: When W b Less than W s hour: (1) When H s Satisfy condition H t +ΔL<H s <H c When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t -ΔL); (2) When H s Satisfy condition H t ≤H s ≤H t When +ΔL, the load-bearing state of the spring hanger is recorded as "normal"; (3) When H s Satisfy condition H s <H t When the spring hanger is loaded, the load state is recorded as "overload", and the overload value W g =K s ·(H t -H s ); When the thermal displacement of the pipe is upward, there are two situations: Case 1: When W b Greater than W s hour: (1) When H s Satisfy condition H c <H s <H t -ΔL, the load state of the spring hanger is recorded as "overload", and the overload value is W g =K s ·(H-ΔL-H s ); (2) When H s Satisfy condition H t -ΔL≤H s ≤H t When , the load-bearing state of the spring hanger is recorded as "normal"; (3) When H s Satisfy condition H s >H t When the spring hanger is underloaded, the load state is recorded as "underloaded", and the underload value W c =K s ·(H s -H t ); Case 2: When W b Less than W s hour: (1) When H s Satisfy condition H c <H s <H t When the spring hanger is loaded, the load state is recorded as "overload", and the overload value W g =K s ·(H t -H s ); (2) When H s Satisfy condition H t ≤H s ≤H t When +ΔL, the load-bearing state of the spring hanger is recorded as "normal"; (3) When H s Satisfy condition H s >H t +ΔL, the load state of the spring hanger is recorded as "underload", and the underload value W c =K s ·(H s -H t -ΔL).

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