Thread Content
Codes for the Acceptance and Storage of Welding Materials 1 Scope These codes apply to the acceptance of various welding materials upon arrival at the factory, as well as to quality management during their storage, keeping, and distribution for use. 2 Referenced Standards GB893 Stainless steel electrodes GB894 Cladding welding electrodes GB3669 Aluminum and aluminum alloy electrodes GB3670 Copper and copper alloy electrodes GB5117 Carbon steel electrodes GB5118 Low-alloy steel electrodes GB5293 Fluxes for submerged arc welding of carbon steel GB8110 Carbon dioxide shielded welding wires GB9460 Copper and copper alloy welding wires GB10044 Cast iron electrodes and wires GB10045 Carbon steel flux-cored wires QG/LG18.10.01 Inspection and testing procedures for incoming goods GB6052 Industrial liquid carbon dioxide GB10624 High-purity argon 3 Electrodes 3.1 Acceptance rules The acceptance of electrodes upon arrival at the factory is carried out by the inspection department on a batch basis. The work procedures are carried out in accordance with QG/LG18.10.01-1996, \"Procedures for Incoming Inspection and Testing\". 3.1.1 Sampling: When each batch of electrodes arrives at the factory for inspection, representative samples shall be taken evenly from at least 3 locations in the required quantity. 3.1.2 Acceptance: For fillet welds using electrodes with a diameter of 3.2 mm or less, mechanical property tests and radiographic inspections are generally not conducted; their properties can be determined based on the test results for electrodes with a diameter of 4.0 mm. If necessary, proceed in accordance with the relevant provisions of the applicable standards. 3.1.2.1 Upon arrival of each batch of electrodes, their geometric dimensions, appearance, flux coating, and chemical composition shall be inspected in accordance with relevant technical standards, and the inspection results must meet the requirements of these standards. 3.1.2.2 a) Performance parameters such as the T-joint of the welding rod, the mechanical properties of the deposited metal, radiographic testing, corrosion resistance, diffused hydrogen content, and the water content in the coating do not require testing, analysis, and inspection for every batch of welding rods that arrive at the factory. b) The above performance tests and inspections are conducted only when the supplier is changed, or when new types or models of welding electrodes are used for new welding processes; the testing methods and inspection results must comply with the provisions of relevant standards. c) For welding rods of a new type or model used for the first time, all performance parameters must be tested and inspected; the testing methods and inspection results shall comply with the provisions of relevant standards. 3.2.3 Re-inspection: If any test fails, that test shall be re-performed twice. When retesting the tensile test, tensile strength, yield strength, and elongation are all considered as items for retesting. Its specimens can be taken from the original test plate or newly welded specimens. The results of the repeated test at double the dose shall meet the requirements specified for such results in the relevant standards. 3.2.4 Inspection Records: The results of each inspection should be recorded and archived for future reference. 4 Welding wire 4.1 Acceptance rules 4.1.1 Welding wire is accepted in batches. Each batch of welding wire shall consist of wires from the same tank number, the same steel grade, and the same diameter. 4.1.2 The surface of the welding wire is inspected visually. The diameter of the welding wire can be measured after removing surface defects using sandpaper or a file, in order to determine the depth of those defects. 4.1.3 The wire is measured in two mutually perpendicular directions within the same cross-section using a measuring tool with an accuracy of 0.001 mm. There shall be no less than two measurement points per coil of welded wire. 4.1.4 When testing the chemical composition of welding wire, 3% of each batch of welding wire shall be selected at random based on the number of coils or bundles, with a minimum of two coils or bundles; samples shall be taken from both ends of each coil or bundle. For carbon, phosphorus, and sulfur, the composition at each end is evaluated separately. Other elements evaluate the average value of the components at both ends. If one of the analysis results is unsatisfactory, it is allowed to take double the amount of samples from the unworn wire coils and bundles in order to retest the element that gave an unsatisfactory result. If any items are still non-compliant, the supplier must inspect them disc by disc and bundle by bundle; only those that pass the inspection can be stored in inventory. Otherwise, it will be treated as unqualified. 4.1.5 The acceptance of other performance indicators shall be carried out in accordance with relevant technical standards (such as the mechanical properties of the deposited metal, the adhesion of the copper coating, the relaxation diameter, and the warping amount, etc.). 5 Fluxes 5.1 The various technical performance indicators of fluxes shall meet the requirements of the standard GB5293-85 \"Fluxes for submerged arc welding of carbon steel\". 5.2 The acceptance methods and test results shall also meet the requirements of the standards. 6 Welding gases 6.1 Carbon dioxide and argon used for welding must meet the requirements specified in GB6502-1993 \"Industrial liquid carbon dioxide\" and GB10624-1995 \"High-purity argon\" – Grade I standards, respectively. 6.2 The acceptance methods and test results for carbon dioxide and argon shall meet the requirements of the above standards. 7 Quality management of welding materials 7.1 Packaging and marking Every welding material must be packaged and marked in accordance with relevant technical standards, and inspection shall be carried out in line with these standards. 7.2 Instructions and Quality Certificates Each welding material shall be accompanied by instructions prepared by the supplier based on its specific properties and quality, as well as a quality certificate issued in light of actual test results, for reference and consultation. 7.3 Storage and Preservation 7.3.1 Welding materials must be stored in a dry and well-ventilated indoor warehouse. Harmful gases and corrosive substances are not allowed to be stored in the welding materials warehouse. The interior should be kept clean. 7.3.2 Welding rods shall be stored on shelves, with the shelves being at a height of not less than 300 mm from the ground and not less than 300 mm from the walls. Desiccant should be placed under it to prevent the welding electrodes from getting damp. 7.3.3 During stacking, it should be organized by type, grade, batch, specification, and date of receipt. Each stack should be clearly labeled to avoid confusion. 7.3.4 It shall be guaranteed to be usable for at least 6 months after being supplied to the user unit. Welding rods stored in the warehouse should be used in order of their arrival date. 7.3.5 Special welding electrodes should be stored and kept at a higher standard than ordinary welding electrodes. Special welding electrodes should be stored in a dedicated warehouse or designated area. Welding rods that are damp or have damaged packaging must not be stored in the warehouse without treatment. 7.3.6 Welding electrodes that are damp, have discolored coatings, or rust on their cores must be dried before quality assessment can be carried out. Only when all performance indicators meet the requirements can it be stored; otherwise, it is not allowed to be stored. 7.3.7 Thermometers and hygrometers should be installed in the welding rod storage area. For low-hydrogen electrodes, the indoor temperature should be no lower than 5°C, and the relative air humidity should be below 60%. 7.3.8 For steel cylinders filled with liquid carbon dioxide and argon, the paint color, markings, and filling factor shall comply with the provisions of the Regulations on Safety Supervision of Gas Cylinders. 7.3.9 Cylinders for liquid carbon dioxide and argon shall be dedicated and must not be used to hold other gases. 7.3.10 Cylinders of liquid carbon dioxide and argon should be placed upright in a well-ventilated and dry area, away from heat and direct sunlight. 7.3.11 The quantity of general welding materials (excluding welding gases) issued at one time shall not exceed the amount required for two days, and welders must keep the electrodes that have been issued properly stored. 7.4 Requirements for personnel in charge of storing welding materials 7.4.1 Before welding materials are stored, it is necessary to check the quality certificate issued by the electrode manufacturer; the packaging of the electrodes must not be damaged, and they must not be damp or exposed to rain before they can be approved for storage. 7.4.2 Carefully verify the type, specification, grade of the welding materials entering the warehouse, and stack them in batches. Distribution is carried out according to the variety, specifications, and quantity specified on the material requisition form. 7.4.3 Welding materials that have been stored for more than one year should be subjected to various performance tests again by the quality inspection department before being issued; they can only be released if they meet the requirements, otherwise they should not be dispatched. 7.4.4 It is necessary to be familiar with the general properties and requirements of different types of welding materials, and to regularly check whether the stored materials are damp or damaged, taking action promptly if such issues are found. The types, specifications, selection, and material consumption of various welding materials must all be verified to prevent errors in storage, delivery, and use, which could lead to quality issues. 7.4.5 Personnel in charge of storing welding materials must be knowledgeable in the field and skilled in management. When distributing, those that were stored first should be issued first. If quality issues are detected during storage, they should be reported to the relevant departments promptly so that appropriate action can be taken to resolve them. 7.5. Requirements for personnel responsible for welding rod quality inspection 7.5.1 They must have a good understanding of the industry, be familiar with the properties, applications, and manufacturing processes of the products, be able to correctly understand and grasp the product standards, and conduct inspections in strict accordance with these standards to ensure quality control. 7.5.2 Be responsible for the quality of the welding materials that have passed acceptance and been stored. It is authorized to stop any violations of relevant regulations in the storage, drying, and use of welding materials. 7.5.3 Welding materials identified as defective after inspection by quality control personnel shall be specially marked and must not be stored in inventory or used in production. Then the situation is reported to the relevant departments for handling. 7.6 Drying and storage of electrodes before use 7.6.1 Before use, electrodes should generally be dried, unless otherwise specified in the electrode instructions. Acidic electrodes should be dried at 75–150°C for 1–2 hours, depending on the degree of moisture absorption ； Alkaline low-hydrogen structural steel welding electrodes should be dried at 350–400°C for 1–2 hours. The dried electrodes should be stored in a chamber (tube) maintained at 100–150°C, and taken out as needed; care should be taken to keep them dry during use. 7.6.2 Low-hydrogen electrodes generally need to be redried if exposed at room temperature for more than 4 hours. The number of repeated drying cycles should not exceed three. 4.6.3 When drying electrodes, it is prohibited to suddenly place them in a high-temperature furnace or take them out of the furnace abruptly to cool them, in order to prevent the coating on the electrodes from cracking or peeling due to sudden changes in temperature. 7.6.4 Records should be kept when drying welding rods, and these records should include details such as the grade, batch number, temperature, and time. 5.6.5 During the drying of welding electrodes, a dedicated technical personnel shall be assigned to monitor and verify the operation process, at least once for each batch of electrodes, and sign the operation record. 7.6.6 When drying electrodes, they should not be stacked in piles or bundles; instead, they should be laid in layers. The thickness of each layer of electrodes should not be too great (usually 1–3 layers), to prevent uneven heating during drying and to make it easier to remove moisture. 7.6.7 When working outdoors over night, welding rods must be stored properly; they should not be left outside, but rather kept at a constant temperature in a low-temperature oven. Otherwise, they need to be dried again before use the next day.