Compressed air energy storage power station underground chamber steel lining weld joint ultrasonic detection reference block

Abstract

The utility model discloses a compressed air energy storage power station underground chamber steel lining weld joint ultrasonic detection reference block which is composed of three parts, namely a transverse through hole area located in the middle and a first step notch groove area and a second step notch groove area located at the two ends. A plurality of transverse through holes with different depths and diameters of 1mm are formed in the transverse through hole area; and a plurality of steps with different heights are arranged in the first step grooving area and the second step grooving area. The depth interval of the transverse through holes of the reference block is small, the hole diameter of the transverse through holes is small, the reference block is provided with the area type defect comparison notch grooves, and the weld defect of the thin-wall steel lining for the underground chamber of the compressed air energy storage power station can be detected qualitatively and quantitatively.

Description

Technical Field

[0001] The utility model belongs to the technical field of compressed air energy storage, and relates to a comparative test block for ultrasonic detection of steel lining welds in underground chambers of compressed air energy storage power stations. Background Art

[0002] At present, the main standard used for power pressure equipment is NB / T47013.3-2015 "Non-destructive testing of pressure equipment Part 3: Ultrasonic testing". According to this standard, the ultrasonic testing test blocks for welded joints of pressure equipment mainly include CSK series test blocks and GS series test blocks. Among them, the standard test blocks used for type I welds are usually CSK-IA test blocks, and the comparison test blocks are mainly CSK-IIA, CSK-IIIA, CSK-IVA, etc.; the standard test blocks used for type II welds are usually GS-1 test blocks, and the comparison test blocks are mainly GS-2, GS-3, GS-4, etc. The above comparison test blocks mainly use transverse through holes as the comparison benchmark. The hole diameter varies according to the applicable thickness range, and the minimum hole diameter is The minimum depth interval is 4mm, which is sufficient for the butt weld inspection of conventional thick-walled pressure-bearing components. However, it is insufficient for the weld inspection of thin-walled steel linings used in underground chambers of compressed air energy storage power stations. The main reasons are:

[0003] (1) The thickness of thin-walled parts is small, and the depth interval of standard universal comparison test blocks is too large to meet the comparison requirements. For example, if the thickness of a steel lining is 6 mm, using the existing comparison test blocks, at most only two cross-hole depths are within the test wall thickness range (the first hole cannot be 0), so the DAC curve is relatively rough within the required test range;

[0004] (2) The aperture of the standard universal test block is large, and the detection sensitivity is low. For example, if the thickness of a steel lining is 6mm, the existing standard minimum aperture is used. Horizontal through hole (reflection surface can be compared to Circular pores, and The circular pores account for 1 / 3 of the plate thickness relative to the 6mm plate thickness, which has a great impact), and their reflection equivalent is relatively too large;

[0005] (3) The transverse through hole is only an equivalent comparison. In actual inspection, defects such as cracks have a greater impact. However, the standard universal comparison test block does not have cracks or other area-type defects for comparison, so there is a lack of effective comparison. Utility Model Content

[0006] The purpose of the utility model is to provide a comparative test block for ultrasonic detection of welds of steel linings in underground chambers of compressed air energy storage power stations. The test block has small depth intervals of transverse through holes, small diameters of transverse through holes, and is provided with area-type defect comparison grooves, which can qualitatively and quantitatively detect weld defects of thin-walled steel linings used in underground chambers of compressed air energy storage power stations.

[0007] The technical solution adopted by the present invention is to provide a comparative test block for ultrasonic testing of steel lining welds in underground chambers of compressed air energy storage power stations. The test block consists of three parts, namely a transverse through hole area in the middle and a first step groove area and a second step groove area at both ends; a plurality of transverse through holes of different depths and a diameter of 1 mm are provided in the transverse through hole area; a plurality of steps of different heights are provided in the first step groove area and the second step groove area.

[0008] The utility model is also characterized in that:

[0009] Six transverse through holes are distributed in the transverse through hole area from top to bottom. The horizontal spacing between each transverse through hole is ≥15mm, the vertical spacing is 3mm, and the distance between the top transverse through hole and the upper surface of the test block is 3mm, and the distance between the bottom transverse through hole and the lower surface of the test block is 2mm.

[0010] The first step groove area includes six steps, the height of each step differs by 3 mm, and the height of the step at the end is 3 mm.

[0011] A groove with a width of 0.1 mm and a depth of 1 mm is provided in the center of the step along the width direction of the test block.

[0012] The second step groove area includes seven steps, the height of each step differs by 3 mm, and the height of the step at the end is 2 mm.

[0013] A groove with a width of 0.1 mm and a depth of 1 mm is provided in the center of the step along the width direction of the test block.

[0014] The material of the test block is the same as that of the steel lining being tested or is 45# steel.

[0015] The Ra of each surface of the test block is ≤0.4um; the parallelism of the end face is ≤5um; there are no obvious scratches, bumps or rust defects on the outer surface.

[0016] The beneficial effects of the utility model are:

[0017] The ultrasonic testing comparison test block of the utility model has a small depth interval of the transverse through holes, a small aperture of the transverse through holes, and an area-type defect comparison groove. The DAC curve of the ultrasonic testing of the steel lining weld produced by using the comparison test block has high accuracy and high defect detection sensitivity. It can also simulate the vertical crack defect at the root of the weld, which is the focus of ultrasonic testing in the steel lining detection scenario, and can greatly improve the accuracy of defect detection and increase the detection rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural diagram of the comparative test block of the utility model;

[0019] Figure 2It is a top view of the comparison test block of the utility model.

[0020] In the figure, 1. transverse through hole area, 2. first step groove area, 3. second step groove area, 4. step, 5. groove, 6. transverse through hole. DETAILED DESCRIPTION

[0021] The present invention will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0022] Example 1:

[0023] The utility model of the ultrasonic testing comparison test block for the steel lining weld of the underground chamber of the compressed air energy storage power station has a structure such as Figure 1 and Figure 2 As shown, the whole is composed of three parts, namely the transverse through hole area 1 located in the middle and the first step groove area 2 and the second step groove area 3 located at both ends; a number of transverse through holes 6 with different depths and a diameter of 1 mm are provided in the transverse through hole area 1; a number of steps 4 with different heights are provided in the first step groove area 2 and the second step groove area 3.

[0024] Example 2:

[0025] Based on Example 1, six transverse through holes 6 are distributed sequentially from top to bottom within the transverse through hole area 1. The horizontal spacing between each transverse through hole 6 is ≥15 mm, and the vertical spacing is 3 mm. The distance between the topmost transverse through hole 6 and the upper surface of the test block is 3 mm, and the distance between the bottommost transverse through hole 6 and the lower surface of the test block is 2 mm. The first stepped groove area 2 includes six levels of steps 4, with the height of each level of steps 4 varying by 3 mm, and the height of the step 4 at the end is 3 mm.

[0026] Example 3:

[0027] The utility model of the ultrasonic testing comparison test block for the steel lining weld of the underground chamber of the compressed air energy storage power station has a structure such as Figure 1 and Figure 2 As shown, it is a block structure with a length ≥310mm, a thickness ≥40mm, and a height of 20mm. Its two ends in the length direction are stepped structures. The whole is composed of three parts, namely the transverse through hole area 1 in the middle and the first stepped groove area 2 and the second stepped groove area 3 at both ends.

[0028] The first stepped groove area 2 includes six steps 4, each with a 3mm height difference, and the step at the end is 3mm high. The width of each groove platform (i.e., step) is ≥15mm, and a groove 5 with a width of 0.1mm and a depth of 1mm is machined in the center of each groove platform along the width direction of the test block to simulate a vertical crack at the root of the weld. When the test block of the utility model is in use, the probe is obliquely incident from the lower surface of the test block to the groove to form an echo. The groove root (i.e., the groove platform surface) is used as the groove depth value. The simulated depths of the side groove area (from the end to the middle) are: 3mm, 6mm, 9mm, 12mm, 15mm, and 18mm, respectively.

[0029] The second stepped grooved area 3 consists of seven steps 4, each with a 3mm height difference, and the step at the end is 2mm high. The width of each grooved platform (i.e., step) is ≥15mm, and a groove 5 with a width of 0.1mm and a depth of 1mm is machined in the center of each platform along the width of the test block to simulate a vertical crack at the weld root. When the test block is in use, the probe is obliquely incident from the upper surface of the test block into the groove to generate an echo. The groove root (i.e., the groove platform surface) is used as the groove depth value. The simulated depths of the grooved area on this side (from end to center) are: 2mm, 5mm, 8mm, 11mm, 14mm, 17mm, and 20mm (located on the lower surface of the test block).

[0030] The middle transverse hole area 1 is distributed with six holes from top to bottom. The horizontal spacing between the transverse through holes 6 is ≥15mm, and the distance between the top hole and the edge of the first stepped groove area 2 is ≥25mm; the vertical spacing is 3mm, and the top hole is 3mm away from the upper surface of the test block; therefore, the depths of the transverse through holes from top to bottom are 3mm, 6mm, 9mm, 12mm, 15mm, and 18mm, and correspondingly, the depths of the transverse through holes from bottom to top are 2mm, 5mm, 8mm, 11mm, 14mm, and 17mm, respectively.

[0031] In summary, the depth of the transverse through hole that can be simulated by the test block of the present invention covers 2mm, 3mm, 5mm, 6mm, 8mm, 9mm, 11mm, 12mm, 14mm, 15mm, 17mm, and 18mm, with a depth interval of 1-2mm. Taking the 6mm steel lining as an example, there are four transverse through holes actually covered within the detection thickness range. Therefore, the DAC curve made using the test block of the present invention is more refined within the required detection range. In addition, the groove depth that can be covered by the test block of the present invention includes 2mm, 3mm, 5mm, 6mm, 8mm, 9mm, 11mm, 12mm, 14mm, 15mm, 17mm, 18mm, and 20mm, with a depth interval of 1-2mm. Considering that the groove depth itself is 1mm, the test block can basically cover the root cracks of the welds of thin-walled steel liners of various thicknesses.

[0032] The overall height of the test block of the utility model is 20 mm, which can cover the current thickness range of the steel lining of the compressed air energy storage underground chamber; the thickness of the test block is ≥40 mm, which meets the requirements of the transverse through hole size required for the ultrasonic inspection test block and can effectively avoid the influence of side wall echo.

[0033] The material of the test block of this utility model is the same as that of the steel lining to be tested or is 45# steel, and its main chemical composition complies with GB699 "High-quality carbon structural steel steel grades and general technical conditions". After normalizing treatment, the grain size reaches level 7 or above, and the internal direction is not greater than Defect signal from ultrasonic reflection signal of flat-bottom hole. Surface roughness of the test block is: Ra≤0.4μm on all surfaces; end face parallelism≤5μm; no obvious scratches, dents, rust, or other defects on the outer surface; the depth of each step groove is marked on the side of the test block.

[0034] The method for drawing the DAC curve (distance amplitude curve) using the test block of the utility model is as follows:

[0035] Using the ultrasonic detector's built-in adjustment program, select the first channel. Based on the steel lining thickness, select all cross-drilled holes within the cross-drilled hole with a depth slightly greater than the steel lining thickness to create a DAC curve (e.g., if the steel lining thickness is 6mm, select cross-drilled holes with depths of 2mm, 3mm, 5mm, 6mm, and 8mm as cross-drilled holes for curve creation). Complete the creation of the distance-amplitude curve, which will serve as a comparison curve. Select the second channel and select a groove depth equal to the thickness of the steel lining to be inspected, or the two groove depths closest to the groove depth, as a reference point (e.g., if the steel lining thickness is 6mm, select a groove depth of 6mm; if the steel lining thickness is 7mm, select groove depths of 6mm and 8mm). Create reference points or lines.

Claims

1. Ultrasonic testing comparison test block for steel lining welds in underground chambers of compressed air energy storage power stations, characterized by: The test block is composed of three parts, namely a transverse through hole area (1) located in the middle and a first step groove area (2) and a second step groove area (3) located at both ends; a plurality of transverse through holes (6) of different depths and each having a diameter of 1 mm are provided in the transverse through hole area (1); a plurality of steps (4) of different heights are provided in both the first step groove area (2) and the second step groove area (3).

2. The ultrasonic testing comparison test block for steel lining welds of underground chambers of compressed air energy storage power stations according to claim 1 is characterized in that: Six transverse through holes (6) are sequentially distributed in the transverse through hole area (1) from top to bottom, the horizontal spacing between each transverse through hole (6) is ≥15 mm, the vertical spacing is 3 mm, and the distance between the top transverse through hole (6) and the upper surface of the test block is 3 mm, and the distance between the bottom transverse through hole (6) and the lower surface of the test block is 2 mm.

3. The ultrasonic testing comparison test block for steel lining welds of underground chambers of compressed air energy storage power stations according to claim 1 is characterized in that: The first stepped groove area (2) comprises six steps (4), the height of each step (4) differs by 3 mm, and the height of the step (4) at the end is 3 mm.

4. The ultrasonic testing comparison test block for steel lining welds of underground chambers of compressed air energy storage power stations according to claim 3 is characterized in that: A groove (5) with a width of 0.1 mm and a depth of 1 mm is provided at the center of the step (4) along the width direction of the test block.

5. The ultrasonic testing comparison test block for steel lining welds in underground chambers of compressed air energy storage power stations according to claim 1 is characterized in that: The second stepped groove area (3) comprises seven steps (4), the height of each step (4) differs by 3 mm, and the height of the step (4) at the end is 2 mm.

6. The ultrasonic testing comparison test block for steel lining welds in underground chambers of compressed air energy storage power stations according to claim 5 is characterized in that: A groove (5) with a width of 0.1 mm and a depth of 1 mm is provided at the center of the step (4) along the width direction of the test block.

7. The ultrasonic testing comparison test block for steel lining welds in underground chambers of compressed air energy storage power stations according to claim 1 is characterized in that: The material of the test block is the same as that of the steel lining to be tested or is 45# steel.

8. The ultrasonic testing comparison test block for steel lining welds in underground chambers of compressed air energy storage power stations according to claim 7, characterized in that: The surface Ra of the test block is ≤0.4um; the end face parallelism is ≤5um; There are no obvious scratches, bumps or rust defects on the outer surface.

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