CN103776853B - A kind of reference block detecting the lack of penetration degree of depth of small diameter tube weld bond - Google Patents

Abstract

The invention provides a comparison test block for detecting the non-penetration depth of a welding joint of a small-diameter pipe, which belongs to the technical field of data monitoring. It solves the problems of inconvenient use of the existing comparison test block used to detect the non-penetration depth of the welding joint of the small-diameter pipe and the inaccurate determination of the non-penetration depth range. The comparison test block includes a tubular test block body, at least one circumferential artificial defect groove is arranged on the inner wall surface of the test block body, and a simulated weld seam is arranged on the outer wall surface of the test block body corresponding to the position of the artificial defect groove. Yu Gao. It simulates the lack of penetration depth by setting artificial defect grooves on the inner wall of the test block body, and simulates the weld seam of the weld joint by setting the simulated weld reinforcement. The comparison during detection is more accurate, obvious and intuitive. It can be directly compared with the pipes to be inspected, and it is more intuitive and quicker to evaluate whether the incomplete penetration depth of the small-diameter pipe welds of the pipes to be inspected exceeds the standard.

Description

A comparative test block for detecting the non-penetration depth of small-diameter pipe welds

technical field

The invention relates to a data detection device, in particular to a comparison test block for detecting the non-penetration depth of a welding joint of a small-diameter pipe.

Background technique

Pressure pipeline is a special pressure-bearing equipment with explosion hazard. It can be used as the core facility of many special equipment or systems, and is responsible for the transportation of high-temperature, high-pressure, flammable, explosive, highly toxic, highly corrosive or radioactive materials. It occupies an important position in the national economic construction. The integrity of the pressure pipeline is directly related to the safety of production. Once leakage or explosion occurs, it often leads to catastrophic accidents. In order to ensure its safe operation, it is very necessary to use appropriate methods to conduct regular inspections on it. There are a lot of defects in the manufacture or use of pressure pipelines. Since the connection of pressure pipelines is mostly welded, the butt weld is often the weak link of the pipeline, which is prone to various defects and damages, especially incomplete penetration. There are the most defects, which pose a serious threat to the safe use of pressure pipelines. Therefore, how to detect the safety of pressure pipelines with incomplete penetration defects is currently a hot topic in academic and engineering research at home and abroad. In order to accurately evaluate the life expectancy and safety of pressure pipelines, it is necessary to accurately measure the depth of incomplete penetration defects. On this basis, the stress check and fracture mechanics estimation can be further carried out, and then the safety of the pipeline can be evaluated.

The comprehensive inspection of pressure pipelines currently in use in my country is currently implemented in the "Periodic Inspection Regulations for Industrial Pipelines in Use" Trial Quality Inspection Pot [2003] No. 108, hereinafter referred to as "Industrial Pipeline Inspection Regulations". Welding defects such as incomplete penetration shall be evaluated according to the provisions of Chapter 4 of the "Industrial Pipeline Inspection Regulations", and may be graded according to local thinning under certain special conditions.

In response to the major accidents that occurred in two ammonia-related enterprises in Changchun, Jilin and Shanghai in 2013, the AQSIQ issued the Quality Inspection Special Letter [2013] No. 61 on November 4, 2013. "Guiding Opinions on Special Treatment of Special Equipment", which provides guidance on the treatment of pressure pipes in refrigeration devices with ammonia as the medium, especially for the allowable non-penetration depth of ammonia refrigeration pressure pipes on the low temperature side.

Everyone in the industry knows that according to JB/T4730.2-2005 "Nondestructive Testing of Pressure Equipment Part 2: Radiographic Testing", for small-diameter tubes with an outer diameter of D ₀ ≤ 100mm, when detecting incomplete penetration, the provisions of Appendix H of the standard are adopted. The special comparison test blocks are Type I _A and Type I _B. The evaluation content of this standard and the test block are only applicable to the case where the ratio of depth to wall thickness of small-diameter pipes without penetration and concave defects at the root is ≤15%.

For the determination of the safety status level of in-use industrial pipelines, according to Article 49 of the "Industrial Pipeline Inspection Regulations", when the material of the pipe is 20 steel, 16Mn or austenitic stainless steel, the incomplete penetration can be graded according to local thinning . The requirements for the allowable non-penetration depth of in-service pressure pipelines have been greatly relaxed. In Quality Inspection Special Letter [2013] No. 61, for ammonia refrigeration pressure pipelines on the low-temperature side assessed by Level 3 safety conditions, it is stipulated that "the ratio of the depth of unwelded penetration to the measured wall thickness of the pipeline is less than 0.6, and the bottom of the defect is the smallest Wall thickness ≥ 2mm". Therefore, the special comparison test blocks specified in the JB/T4730.2-2005 standard and its appendix H of the standard, that is, Type I _A and Type I _B , are no longer applicable to the radiation in the depth range of incomplete penetration defects required by the above regulations and documents. detection. Therefore, it is necessary to find a new contrast test block for radiographic detection to meet the new requirements of existing regulations and documents.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned problems in the existing technology, and proposes a comparison test block for detecting the non-penetration depth of the small-diameter pipe weld. Putting the pipes together for comparison, it is more intuitive and quicker to evaluate whether the non-penetration depth of the welded joint of the small-diameter pipe exceeds the standard.

The purpose of the present invention can be achieved through the following technical solutions: a comparison test block for detecting the incomplete penetration depth of the weld joint of a small-diameter pipe, which is characterized in that it includes a tubular test block body, and the inner wall surface of the test block body is set There is at least one circumferential artificial defect groove, and a simulated weld reinforcement is set on the outer wall of the test block body corresponding to the artificial defect groove.

The small-diameter pressure pipes to be tested are generally small in diameter and wall thickness, and the diameter and wall thickness of pressure pipes are small. The welds are generally circular butt welds and single-sided welds, and the inner surface is prone to incomplete penetration defects, and defects It is also generally circular. In this technical solution, a tube with the same or similar ray absorption coefficient as the material of the pipeline to be tested is used as a comparison test block, and the diameter of the comparison test block is the same or similar to that of the pipeline to be tested. The inner wall surface of the block body is provided with a circular artificial defect groove similar to the above-mentioned incomplete penetration defect, and a simulated weld reinforcement with a certain height is arranged on the outer wall surface corresponding to the position of the artificial defect groove. The blackness contrast can be carried out by radiographic inspection, so as to detect and evaluate the non-penetration depth of the weld joint of the small-diameter pipe.

In the above comparison test block for detecting the non-penetration depth of the welding joint of the small-diameter pipe, the number of the artificial defect grooves is 3, and the distance between the adjacent artificial defect grooves is 3-20mm. The comparison test block with 3 artificial defect grooves can be used as a general-purpose non-penetration depth comparison test block. When evaluating the non-penetration depth range of the pipeline to be tested, the non-penetration blackness of the pipe weld is compared with the comparison test block respectively. The blackness of the three artificial defect grooves is judged, so as to obtain the depth range of the incomplete penetration defect.

In the above comparison test block for detecting the non-penetration depth of the small-diameter pipe weld, the groove width of the artificial defect groove is 1.0-2.5 mm, and the groove depth is 0.5-2.0 mm. The above values are applicable to the defect standards stipulated in the "Regulations for Periodic Inspection of Industrial Pipelines in Use" (Trial).

In the above comparison test block for detecting the non-penetration depth of the small-diameter pipe weld joint, the number of the artificial defect groove is one. The comparison test block with only a single artificial defect groove can be used as the non-penetration depth comparison test block for ammonia pipelines, which is used as the standard test block. The above values are applicable to the defect standards specified in the quality inspection letter [2013] No. 61. When the comparison of the non-penetration depth of the ammonia pipeline to be tested exceeds the comparison test block, it is assessed as having a safety status level exceeding Level 3.

In the above comparative test block for detecting the non-penetration depth of the welding joint of the small-diameter pipe, the groove width of the artificial defect groove is 1.0-2.5 mm, and the groove depth is 0.5-2.5 mm.

In the above comparative test block for detecting the non-penetration depth of the small-diameter pipe weld, the outer diameter of the pipe of the test block body is 25-89 mm, and the thickness of the pipe wall is 2.0-5.0 mm. The dimensions above are general dimensions for small diameter tubing.

In the above comparison test block for detecting the non-penetration depth of the small-diameter pipe weld joint, the height of the test block body is 80-150 mm. Preferably it is 100 mm.

In the above comparison test block for detecting the non-penetration depth of the weld joint of the small-diameter pipe, the simulated weld reinforcement is an outwardly protruding annular rim provided on the outer wall surface of the test block body. The ring-shaped convex edge is directly processed by the thick-walled pipe, and it has an integrated structure with the thick-walled pipe, which is not easy to be damaged and falls off, and has a long service life.

In the above-mentioned comparison test block for detecting the non-penetration depth of the small-diameter pipe weld joint, the simulated weld reinforcement is a circular welding layer protruding outward on the outer wall surface of the test block body through artificial simulation welding. The ray absorption coefficient of the artificial manual welding layer is closer to that of the weld seam on the pipeline to be detected, and the comparative detection effect is more accurate.

In the above comparison test block for detecting the non-penetration depth of the small-diameter pipe weld joint, the height of the simulated weld reinforcement is 0.5-3.0 mm. The value is mostly 1.5-2.5mm, and the preferred value is 2mm. The width of the simulated weld reinforcement should exceed the sufficient width of the two edges of the artificial defect groove to prevent image overlap.

Compared with the prior art, the present invention has the following advantages: the comparison test block is simple and convenient to use, and the test block body can be directly placed together with the small-diameter tube to be detected, and irradiated by a ray source, so as to obtain weld seam The blackness value of the test block is directly compared with the blackness value of the comparison test block. The depth comparison process is more obvious and intuitive, and it can quickly evaluate whether the non-penetration depth of the small-diameter pipe weld meets the standard.

Description of drawings

FIG. 1 is a schematic structural diagram of Embodiment 1 of the present invention.

Fig. 2 is a sectional view of Embodiment 1 of the present invention.

Fig. 3 is a cross-sectional view of Embodiment 2 of the present invention.

Fig. 4 is a sectional view of Embodiment 3 of the present invention.

Fig. 5 is a sectional view of Embodiment 4 of the present invention.

In the figure, 1. The body of the test block; 2. The simulated weld reinforcement; 3. The artificial defect groove; A. The spacing of the artificial defect groove of the general comparison test block; a. The groove width of the artificial defect groove; L. The test block body H, simulated weld reinforcement; h1, artificial defect groove depth of the general comparison test block; h2, artificial defect groove depth of the general comparison test block; h3, artificial defect of the general comparison test block Groove depth three; h4, artificial defect groove depth of ammonia pipeline special comparison test block.

detailed description

The following are specific embodiments of the present invention and in conjunction with the accompanying drawings, further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

Embodiment one:

Referring to Fig. 1 , the first embodiment is a general-purpose comparison test block for detecting the non-penetration depth of the weld joint of a small-diameter pipe with an outer diameter D ₀ ≤ 100 mm. This type of comparison test block includes a tubular test block body 1, The inner wall surface of the test block body 1 is provided with three circumferential artificial defect grooves 3, and the outer wall surface of the test block body 1 corresponding to the position of the artificial defect groove 3 is provided with a simulated weld reinforcement 2, and the simulated weld reinforcement The width of 2 shall not be less than the overall width of the three artificial defect grooves 3, that is, the width of the simulated weld reinforcement 2 shall exceed the sufficient width of the two side edges of the artificial defect groove 3 to prevent overlapping of images, and be able to fully simulate the joint position of small-diameter pipes For the welding layer structure, the height L of the test block body 1 is 80-150 mm, preferably 100 mm. In this embodiment, the simulated weld reinforcement 2 is integrated with the test block body 1. It is directly processed by thick-walled pipes and is located on the outer wall of the test block body 1. The height of the seam residue 2 is 0.5-3.0 mm, generally 1.5-2.5 mm, preferably 2 mm. In this embodiment, the groove widths of the three artificial defect grooves 3 range from 1.0 to 2.5 mm, while the groove depths are different, and increase or decrease sequentially. The groove depth ranges from 0.5 to 2 mm. The adjacent two artificial defect grooves 3 The spacing A between them is equal, and the spacing A is 3 to 20 mm.

The size of the comparison test block in this embodiment generally has a specific value in order to be compatible with the small-diameter tube to be detected, and the specific values are shown in the following table:

Unit: mm

Embodiment two:

Referring to Fig. 3, the structure of the second embodiment is basically the same as that of the first embodiment, the difference is that the simulated weld reinforcement 2 of the comparative test block in the second embodiment is artificially welded on the outer wall of the test block body 1 The outwardly protruding annular welding layer can fully simulate the welding joint at the butt joint of small-diameter pipes, and the simulation degree is higher.

The dimensions and specifications of the comparative test block in the second embodiment are the same as those in the first embodiment.

Embodiment three:

Referring to Fig. 4, the third embodiment is a special-purpose comparison test block for detecting the non-penetration depth of the welding joint of a small-diameter ammonia pipeline with an outer diameter D ₀ ≤ 100 mm. This type of comparison test block includes a tubular test block body 1. A circular artificial defect groove 3 is provided on the inner wall surface of the test block body 1, and a simulated weld reinforcement 2 is provided on the outer wall surface of the test block body 1 corresponding to the artificial defect groove 3, and the simulated weld seam The width of the reinforcement 2 should exceed enough width of the two side edges of the artificial defect groove 3 to avoid image overlap, and can fully simulate the welding layer structure at the butt joint position of the small-diameter ammonia pipeline. The height L of the test block body 1 is 80-150 mm, preferably 100mm. The simulated weld reinforcement 2 in this embodiment is an integral structure with the test block body 1, which is directly processed by a thick-walled tube and is located on the outer wall of the test block body 1 and protrudes outward. The height of the weld reinforcement 2 is 1.5-2.5 mm, preferably 2 mm. In this embodiment, the groove width of the artificial defect groove 3 ranges from 1.0 to 2.5 mm, and the groove depth ranges from 0.5 to 2.5 mm.

The size of the comparative test block in this embodiment has a specific value in order to be compatible with the small-diameter ammonia pipeline to be detected, and the specific values are shown in the following table:

Unit: mm

The outer diameter Ф of the comparison test block The wall thickness δ of the comparison test block Groove width a Groove depth h4 25 2.5 1.0 0.5 38 3 1.0 1.0 45 3 1.0 1.0 57 3.5 1.5 1.5 76 4 2.0 2 89 4 2.0 2 89 4.5 2.0 2.5

Embodiment four:

Referring to Fig. 5, the structure of the fourth embodiment is basically the same as that of the third embodiment, the difference is that the simulated weld reinforcement 2 of the comparative test block in the fourth embodiment is manually welded on the outer wall surface of the test block body 1 The outwardly protruding annular welding layer can fully simulate the welding joint at the butt joint of small-diameter pipes, and the simulation degree is higher.

The dimensions and specifications of the comparative test block in the fourth embodiment are the same as those in the third embodiment.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which the present invention belongs can make various modifications or supplements to the described specific embodiments or adopt similar methods to replace them, but they will not deviate from the spirit of the present invention or go beyond the definition of the appended claims range.

Although this paper mostly uses the test block body 1, the simulated weld reinforcement 2, the artificial defect groove 3, the spacing A of the artificial defect groove of the general comparison test block, the groove width a of the artificial defect groove, and the height L of the test block body , the height H of the simulated weld reinforcement, the artificial defect groove depth of the general comparison test block is h1, the artificial defect groove depth of the general comparison test block is two h2, the artificial defect groove depth of the general comparison test block is three h3, ammonia The artificial defect groove depth h4 of the pipe-specific comparison test block and other terms, but the possibility of using other terms is not excluded. These terms are used only for the purpose of describing and explaining the essence of the present invention more conveniently; interpreting them as any kind of additional limitation is against the spirit of the present invention.

Claims (10)

1. A comparison test block for detecting the non-penetration depth of a small-diameter pipe weld, it is characterized in that, comprising a tubular test block body (1), the inner wall of the test block body (1) is provided with at least one ring The artificial defect groove (3) in the direction, the outer wall surface of the test block body (1) corresponding to the position of the artificial defect groove (3) is provided with a simulated weld reinforcement (2), and the simulated weld reinforcement ( 2) is greater than the width of the artificial defect groove (3), and both ends of the simulated weld reinforcement (2) in the width direction exceed both ends of the artificial defect groove (3) in the width direction. 2. the comparative test block of detecting the non-penetration depth of small-diameter pipe welding joint according to claim 1, is characterized in that, the number of described artificial defect groove (3) is 3, and described adjacent artificial defect groove (3) The distance between them is 3-20mm. 3. The comparison test block for detecting the non-penetration depth of the small-diameter pipe weld according to claim 2, characterized in that, the groove width of the artificial defect groove (3) is 1.0-2.5 mm, and the groove depth is 0.5-2.0 mm. mm. 4. The comparison test block for detecting the non-penetration depth of the welding joint of small-diameter pipes according to claim 1, characterized in that, the number of the artificial defect grooves (3) is one. 5. The comparison test block for detecting the non-penetration depth of the small-diameter pipe weld according to claim 4, characterized in that, the groove width of the artificial defect groove (3) is 1.0-2.5 mm, and the groove depth is 0.5-2.5 mm. mm. 6. The comparison test block for detecting the non-penetration depth of a small-diameter pipe weld according to claim 1 or 2 or 3 or 4 or 5, characterized in that, the outer diameter of the pipe of the test block body (1) is 25 ~ 89mm, the thickness of the tube wall is 2.0-5.0mm. 7. The comparison test block for detecting the non-penetration depth of the small-diameter pipe weld according to claim 1 or 2 or 3 or 4 or 5, characterized in that the height of the test block body (1) is 80-150 mm. 8. According to claim 1 or 2 or 3 or 4 or 5, the comparison test block for detecting the non-penetration depth of the small-diameter pipe weld joint is characterized in that, the simulated weld reinforcement (2) is arranged on the test block The outer wall surface of the main body (1) is an outwardly protruding annular flange. 9. According to claim 1 or 2 or 3 or 4 or 5, the comparison test block for detecting the non-penetration depth of the small-diameter pipe weld joint is characterized in that, the simulated weld reinforcement (2) is artificially simulated welding A ring-shaped welding layer protruding outward on the outer wall surface of the test block body (1). 10. According to claim 1 or 2 or 3 or 4 or 5, the comparison test block for detecting the non-penetration depth of the small-diameter pipe weld joint is characterized in that the height of the simulated weld reinforcement (2) is 0.5- 3.0mm.