CN109202336B - Preparation method of welding material deposited metal SOHIC test piece - Google Patents

Preparation method of welding material deposited metal SOHIC test piece Download PDF

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Publication number
CN109202336B
CN109202336B CN201811398863.3A CN201811398863A CN109202336B CN 109202336 B CN109202336 B CN 109202336B CN 201811398863 A CN201811398863 A CN 201811398863A CN 109202336 B CN109202336 B CN 109202336B
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welding
test
test plate
welding material
sohic
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CN109202336A (en
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魏家斌
杨永强
王鹏雁
魏楚海俪
牛宗志
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Sinopec Tenth Construction Co Ltd
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Sinopec Tenth Construction Co Ltd
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K37/00Auxiliary devices or processes, not specially adapted to a procedure covered by only one of the preceding main groups

Abstract

The invention relates to a preparation method of a welding material deposited metal SOHIC test piece, belonging to the field of preparation and performance evaluation of a test piece for detecting the corrosion resistance of a sulfur-resistant welding flux in a high-hydrogen sulfide field, and comprising the following steps of cleaning the surface of a test plate; preheating a test plate, performing surfacing on the surface of the test plate, wherein the welding direction of the next layer is opposite to the welding direction of the previous layer; removing the surface metal layer of the welding material cladding layer, and cutting and sampling according to the standard; the test plate is a low-alloy high-strength steel plate, and the preheating temperature is 100-150 ℃; controlling the temperature between layers to be less than 250 ℃ in the process of overlaying welding; the obtained welding material deposited metal has uniform chemical components, stable structure and moderate grain size. Truly reflecting the self sulfur resistance of the sulfur-resistant welding material.

Description

Preparation method of welding material deposited metal SOHIC test piece
Technical Field
The invention belongs to the field of preparation and performance evaluation of a test piece for detecting the corrosion resistance of a sulfur-resistant solder in a high-hydrogen sulfide field, and particularly relates to a preparation method of a welding material deposited metal SOHIC corrosion-resistant test piece.
Background
The main means for evaluating the corrosion resistance of the sulfur-resistant material at present is to perform a sulfide stress cracking test (SSC) and a Hydrogen Induced Cracking (HIC) test of a standard solution on the sulfur-resistant material according to NACETM0177-2005 (laboratory test method for metal sulfide stress corrosion cracking resistance and stress corrosion cracking resistance under H2S environment) and NACETM0284-2005 (test method for evaluating hydrogen induced cracking resistance of steel for pipelines and pressure containers), so as to determine the sulfur resistance of the material by taking the two tests as the standard.
However, the hydrogen induced cracking test (HIC) can only detect and evaluate the corrosion and cracking of the material in a stress-free state, and the material of pipelines, equipment and the like inevitably has various stresses in the use process in the actual production, so that the actual corrosion resistance of the material cannot be accurately evaluated by singly carrying out the HIC test on the material. Furthermore, it has been found that some low sulfur materials have little or no defects caused by HIC when observed in the HIC test in the absence of external stress conditions, but that some low sulfur steels exhibit susceptibility to SOHIC under tensile load. Therefore, for welding materials and steel materials with good HIC resistance, the welding performance, the smelting process and the microstructure formed by the smelting process can still have the sensitivity to the SOHIC, so the SOHIC can reflect the real corrosion resistance of the materials better than the HIC, and the SOHIC test is necessary to evaluate the corrosion resistance of the materials more accurately.
In addition, the corresponding material standards and specifications at home and abroad only stipulate the preparation method of the stress-induced hydrogen cracking (SOHIC) corrosion-resistant test piece of the sulfur-resistant pipe, the plate and the welding joint thereof, and the preparation method of the stress-induced hydrogen cracking (SOHIC) corrosion-resistant test piece of the deposited metal of the welding material is not stipulated. Since there is no definite sample preparation method for the sulfur-resistant welding material, the sulfur-resistant welding material cannot be determined whether the SOHIC resistance under stress condition can meet the actual requirement or not by the corrosion resistance test at present. How to comprehensively detect the corrosion resistance of the sulfur-resistant welding material is always a technical bottleneck restricting the use of the sulfur-resistant material.
Disclosure of Invention
In view of the problems in the prior art, an object of the present invention is to provide a method for preparing a welding material deposited metal SOHIC test piece. The method solves the problem that whether the sulfur resistance of the sulfur-resistant welding material under the stress condition can meet the actual requirement or not can not be determined through a corrosion resistance test in the prior art, and combines the method for preparing the standard test piece for the stress-induced hydrogen cracking (SOHIC) corrosion resistance test of the conventional sulfur-resistant pipe and plate material according to the mechanism of the stress-induced hydrogen cracking (SOHIC) resistance of the sulfur-resistant welding material.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a preparation method of a welding material deposited metal SOHIC test piece comprises the following specific steps:
1) selecting a test plate, and cleaning the surface of the test plate;
2) preheating a test plate, performing surfacing on the surface of the test plate, wherein the welding direction of the next layer is opposite to the welding direction of the previous layer, and obtaining a welding material cladding layer;
3) and removing the surface metal layer of the welding material cladding layer, and cutting and sampling according to the standard.
Preferably, the test plate in the step 1) is a low-alloy high-strength steel plate.
The low-alloy high-strength steel plate is selected to ensure that the test plate does not have obvious deformation in the surfacing process, the mechanical property of the welding material deposited metal is influenced, and excessive impurity elements are prevented from being mixed into the welding material deposited metal, so that the objective evaluation on the SOHIC resistance of the welding material is influenced.
Preferably, the surface cleaning is performed by using a grinder in the step 1).
Preferably, the test plate in the step 1) is (400-.
In order to prevent the influence of welding deformation on the subsequent sample preparation, the surfacing test plate has enough tensile strength and test plate thickness to ensure that the surfacing test plate has enough strength and rigidity to reduce the probability of welding deformation.
Preferably, the temperature for preheating the test plate in the step 2) is 100-150 ℃.
Preferably, the bead of the overlay welding in the step 2) is 10-15 layers.
The number of the overlaying layers is obtained through continuous tests, and when materials sensitive to SOHIC are welded, welding heat input must be strictly controlled, so that a coarse grain structure is avoided. Therefore, control of the welding heat input is achieved by defining the number of weld deposits on the one hand, and the heat input amount is defined by defining welding parameters, interlayer temperature, and the like on the other hand.
Preferably, the process of the build-up welding in step 2) controls the inter-layer temperature to be less than 250 ℃.
Preferably, the welding direction of each layer is the same in the process of overlaying in the step 2), and each layer of welding bead is welded from the middle to two sides. By adopting the welding mode, the growth direction of the columnar crystal is disturbed, and the interlayer temperature is controlled in a combined manner, so that a uniform deposited metal structure is obtained, and the SOHIC resistance of the metal structure can be evaluated objectively.
Preferably, the thickness of the deposited metal deposited in the step 2) is 22-25 mm; the width is 150-160 mm; the length is shorter than the length of the test piece and greater than 320 mm.
The sufficient thickness of the weld metal is to reduce the influence of the base material of the test panel on the dilution of the weld metal, and the size is required to be 305 × 38 × 13mm in order to facilitate the cutting of the SOHIC sample.
Preferably, the thickness of the surface metal layer removed in step 3) is 2.5-3.5 mm.
Preferably, the direction of cutting in step 3) is perpendicular to the welding direction.
The sampling of the SOHIC test piece is perpendicular to the welding direction, and the stress condition of the SOHIC test piece is mainly considered to be consistent with that of the actual pipeline girth weld.
A method for overlaying a welding material to be detected on a steel plate is adopted, welding a welding material deposited metal with a certain thickness, uniform chemical components, stable structure and moderate grain size is carried out, then a test piece for a stress-oriented hydrogen-induced cracking (SOHIC) test of the welding material deposited metal is prepared according to NACE TM0103-2003 (a laboratory test method for evaluating the stress-oriented hydrogen-induced cracking resistance of the steel plate in a wet hydrogen sulfide environment) and NACETM0177-2016 (a laboratory test method for evaluating the environment cracking resistance of a special form of environment cracking material in an H2S environment), and the corrosion resistance of the sulfur-resistant welding material is tested by carrying out a stress-oriented hydrogen-induced cracking (SOHIC) test of standard liquid on the welding material deposited metal.
The invention has the beneficial effects that:
compared with the prior art, the method for preparing the stress-oriented hydrogen induced cracking (SOHIC) corrosion resistance test standard test piece has the beneficial effects that: the method comprises the steps of symmetrically overlaying welding material deposited metal with a certain thickness on a test plate with a certain strength grade, enabling technical indexes such as chemical components, tissue structures, grain sizes, mechanical properties and the like of the welding material deposited metal overlaid on the test plate to be close to actual properties of a test welding material through measures such as multilayer welding, welding direction control, welding stress control and deformation control, and then preparing test pieces for a stress-oriented hydrogen induced cracking (SOHIC) test of the welding material deposited metal according to standards of NACE TM0103-2003 (a laboratory test method for evaluating the stress-oriented hydrogen induced cracking resistance of a steel plate in a wet hydrogen sulfide environment) and NACE TM0177-2016 (a laboratory test method for resisting environmental cracking materials in a special form in an H2S environment). The results of the corrosion resistance comparative tests of 9 welding materials and 13 groups of welding material deposited metals of three corrosion resistance laboratories on the sample prepared by the method in the general smooth gas field ground gathering and transportation project show that the self sulfur resistance of the sulfur-resistant welding material is basically and truly reflected.
Through later-stage tracking observation, the welding material qualified by the evaluation of the SOHIC resistance performance test is applied to construction of a high-sulfur-content gas field of a plain gas field, and the quality problem related to welding seams is not generated when the pipeline runs safely from 2008 to the present.
Practice tests prove that the method has certain guiding significance in the SOHIC resistance evaluation of the welding material, and fills the gap that the SOHIC resistance evaluation of the welding material is not performed at home and abroad at present.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.
FIG. 1 is a schematic view of a build-up test plate, a build-up layer size and a build-up direction according to the present invention;
FIG. 2 is a schematic diagram of stress-guided hydrogen induced cracking (SOHIC) sampling of a weld deposit metal;
wherein the content of the first and second substances,
1. build-up welding layer, 2, substrate.
Detailed Description
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
The invention will be further illustrated by the following examples
Example 1
As shown in fig. 1
The test plate is a low-alloy high-strength steel plate Q345R, and the specification of the test plate is 450 multiplied by 300 multiplied by 30 mm;
selecting a test plate for surfacing, thoroughly cleaning the surface of the test plate by using a grinding wheel machine, heating the test plate to 100-plus 150 ℃ by using flame, carrying out horizontal surfacing welding on the test plate, strictly controlling the energy of a welding line in the welding process, after welding a layer of welding bead on one side of the test plate, controlling the interlayer temperature to be not higher than 250 ℃, symmetrically welding each layer of welding bead from the middle to two sides, wherein the welding direction of each layer of welding bead is all consistent, and the welding direction of an upper layer of welding bead is opposite to that of a lower layer of welding bead. Each surface of the test plate needs 10-15 layers of welding beads, the thickness of welding material deposited metal is 22-25mm, the width is 150-160mm, the length is above 320mm, the surface of the welding material deposited metal is removed by 3mm, and a corrosion-resistant test piece is manufactured in a machining mode in the direction perpendicular to the welding direction.
The horizontal position is adopted for surfacing, so that the operation difficulty is reduced, the heat input is reduced, the burning loss of alloy elements is reduced, and the uniform structure of deposited metal of a welding material is ensured.
Taking the center of the test plate as a boundary line, carrying out surfacing symmetrically from the middle to two sides, namely welding a first welding bead from the left side of the center line, welding a second welding bead on the right side of the center line, and so on; stress and deformation generated by welding are reduced by symmetrical welding;
the first layer of welding material deposited metal is welded in the left-to-right direction, the second layer of welding material deposited metal is welded in the right-to-left direction, and the grain thickness is guaranteed to be uniform through the staggered welding directions.
The bead of the build-up welding is 10 layers.
The thickness of the deposited metal of the surfacing welding material is 22mm, the width is 150mm, and the length is 320 mm.
As shown in fig. 2, a stress-induced hydrogen cracking (SOHIC) corrosion-resistant test piece was produced by removing about 3mm of a weld deposit metal, which is likely to cause composition segregation, from the upper surface of a build-up weld test piece before the test piece was prepared, and then cutting the weld deposit metal from the center of the test piece toward both sides in the direction perpendicular to the welding direction.
Example 2
The detection method of the corrosion resistance test sample of the welding material deposited metal comprises the following steps:
the corrosion-resistant test piece of the welding material obtained in example 1 was subjected to an SOHIC test, and after the test, the surface of the test piece was cleaned, and visually inspected with a magnifying glass of 10 times or more, and the cracking and bubbling conditions of the surface of the test piece were observed.
Two sections of the sample after visual inspection are made in the direction perpendicular to the slot, and are subjected to polishing inspection, and SOHIC expansion degree determination is performed on 4 sections of two test pieces at magnification of 100 times, including CCL (continuous crack length), DCL (discontinuous crack length), and TCL (total crack length), whether the design requirements are satisfied or not.
Through tests such as SOHIC, HIC (hydrogen induced cracking), SSC (sulfide stress cracking) and the like, whether the selected welding material can be suitable for welding of the pipeline in a high-sulfur-content state is judged accurately and objectively.
The results of comparative corrosion resistance tests using the above method on 9 types of welding materials and 13 welding material deposited metals from three corrosion resistance laboratories were performed on the general gas field surface gathering and transportation project using the method of example 1, and are shown in the following table.
TABLE 1 test results of sulfur resistance of various kinds of welding materials
Kind of welding material SOHIC HIC SSC
Carbon steel welding rod LB-52RC Satisfy the requirement of Satisfy the requirement of Satisfy the requirement of
Carbon steel welding rod FOX EV50 Satisfy the requirement of Satisfy the requirement of Satisfy the requirement of
Metal cored wire Metalloy71 Satisfy the requirement of Satisfy the requirement of Satisfy the requirement of
Metal cored wire Metalloy71SG Satisfy the requirement of Satisfy the requirement of Satisfy the requirement of
Carbon steel metal powder cored welding wire Metalloy80N1 Not meet the requirements of Satisfy the requirement of Satisfy the requirement of
Carbon steel metal powder cored welding wire MC460VD-H1 Not meet the requirements of Satisfy the requirement of Satisfy the requirement of
Carbon steel argon arc welding wire EML5 Satisfy the requirement of Satisfy the requirement of Satisfy the requirement of
Carbon steel gas shielded welding wire EMK6 Not meet the requirements of Satisfy the requirement of Satisfy the requirement of
Carbon steel welding rod J507Fe-1 Not meet the requirements of Satisfy the requirement of Satisfy the requirement of
Carbon steel welding rod J507SH Not meet the requirements of Satisfy the requirement of Satisfy the requirement of
Carbon steel welding rod CONARC49C Satisfy the requirement of Satisfy the requirement of Satisfy the requirement of
Carbon steel welding rod CONARC52C Not meet the requirements of Satisfy the requirement of Satisfy the requirement of
Carbon steel argon arc welding wire LNT26 Not meet the requirements of Satisfy the requirement of Satisfy the requirement of
The test result shows that for welding materials of different materials, the sulfur resistance of the sulfur-resistant welding material is truly reflected, and the problem that the SOHIC resistance of the sulfur-resistant welding material under the stress condition cannot be determined through a corrosion resistance test is solved.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (6)

1. A preparation method of a welding material deposited metal SOHIC test piece is characterized by comprising the following steps: the method comprises the following specific steps:
1) selecting a test plate, and cleaning the surface of the test plate;
2) preheating a test plate, and performing single-side surfacing on the surface of the test plate, wherein the welding direction of the next layer is opposite to the welding direction of the previous layer;
3) removing the surface metal layer of the welding material cladding layer, and cutting and sampling according to the standard;
the test plate is a low-alloy high-strength steel plate;
the welding bead of the surfacing in the step 2) is 10-15 layers;
controlling the temperature between layers to be less than 250 ℃ in the surfacing process in the step 2);
in the surfacing process in the step 2), the welding direction of each layer is the same, and each layer of welding bead is welded from the middle to two sides;
the thickness of the deposited metal deposited in the step 2) is 22-25 mm; the width is 150-160 mm; the length is shorter than the length of the test piece and greater than 320 mm.
2. The method of claim 1, wherein: and in the step 1), a grinder is used for surface cleaning.
3. The method of claim 1, wherein: the test plate in the step 1) is (400-500) -250-350-25-35 mm, and the tensile strength is more than 490 MPa.
4. The method of claim 1, wherein: the preheating temperature of the test plate in the step 2) is 100-150 ℃.
5. The method of claim 1, wherein: the thickness of the surface metal layer removed in the step 3) is 2.5-3.5 mm.
6. The method of claim 1, wherein: the cutting direction in the step 3) is perpendicular to the welding direction.
CN201811398863.3A 2018-11-22 2018-11-22 Preparation method of welding material deposited metal SOHIC test piece Active CN109202336B (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20090030590A (en) * 2007-09-20 2009-03-25 주식회사 포스코 Steel plate with high sohic resistance at the h2s containing environment
CN102053024A (en) * 2009-10-30 2011-05-11 中国石化集团第十建设公司 Method for manufacturing test piece of hgdrogen induced cracking (HIC) and sulfide stress cracking (SSC) of welding material melting laid metal
CN102310291A (en) * 2011-08-31 2012-01-11 上海锅炉厂有限公司 Dissimilar steel cold crack sensitivity test method
CN206671103U (en) * 2017-03-20 2017-11-24 天津钢管集团股份有限公司 A kind of device of hydrogen cracking by stress test sample loading
CN108127230A (en) * 2017-12-04 2018-06-08 鲁西工业装备有限公司 A kind of band pole submerged arc overlay welding method of N10276 alloys
CN108267396A (en) * 2018-04-17 2018-07-10 中国石油工程建设有限公司 The apparatus and method that evaluation pipe line steel is tested in acidic environment moderate resistance cracking sensitivity

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20090030590A (en) * 2007-09-20 2009-03-25 주식회사 포스코 Steel plate with high sohic resistance at the h2s containing environment
CN102053024A (en) * 2009-10-30 2011-05-11 中国石化集团第十建设公司 Method for manufacturing test piece of hgdrogen induced cracking (HIC) and sulfide stress cracking (SSC) of welding material melting laid metal
CN102310291A (en) * 2011-08-31 2012-01-11 上海锅炉厂有限公司 Dissimilar steel cold crack sensitivity test method
CN206671103U (en) * 2017-03-20 2017-11-24 天津钢管集团股份有限公司 A kind of device of hydrogen cracking by stress test sample loading
CN108127230A (en) * 2017-12-04 2018-06-08 鲁西工业装备有限公司 A kind of band pole submerged arc overlay welding method of N10276 alloys
CN108267396A (en) * 2018-04-17 2018-07-10 中国石油工程建设有限公司 The apparatus and method that evaluation pipe line steel is tested in acidic environment moderate resistance cracking sensitivity

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