Construction machinery - General specifications for welding parts
1 Scope
This standard specifies the requirements, test method, inspection rules as well as marking, packaging, transportation and storage for welding part of construction machinery products.
This standard is applicable to welding parts processed with manual metal arc welding, submerged arc welding and gas-shield arc welding.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 985.1 Recommended joint preparation for gas welding, manual metal arc welding, gas-shield arc welding and beam welding
GB/T 985.2 Recommended joint preparation for submerged arc welding
GB/T 1804-2000 General tolerances - Tolerances for linear and angular dimensions without individual tolerance indications
GB/T 2650 Impact test methods on welded joints
GB/T 2651 Tensile test method on welded joints
GB/T 2652 Tensile test methods on weld and deposited metal
GB/T 2653 Bend test methods on welded joints
GB/T 2654 Hardness test methods on welded joints
GB/T 2828.1 Sampling procedures for inspection by attributes - Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection
GB/T 3323 Radiographic examination of fusion welded joints in metallic materials
GB/T 4160 Steel-strain ageing sensibility test (Charpy impact method)
GB 9448 Safety in welding and cutting
GB/T 11345 Non-destructive testing of welds - Ultrasonic testing - Techniques, testing levels, and assessment
GB/T 26952 Non-destructive testing of welds - Magnetic particle testing of welds - Acceptance levels
GB/T 26953 Non-destructive testing of welds - Penetrant testing of welds - Acceptance levels
3 Requirements
3.1 General requirements
The welding parts shall be manufactured according to the product drawings and technical documents approved by the prescribed procedures and shall comply with the provisions of this standard. When welding in the open air, windproof, moisture-proof (rain-proof, snow-proof, etc.) measures shall be taken. In the absence of preheating process requirements, when the ambient temperature in the workshop is lower than 0℃, the part to be welded of the workpiece must be preheated to more than 10℃ before welding.
3.2 Material requirements of welding parts
3.2.1 The steel grade, specifications and dimensions of the raw materials used for welding parts shall meet the requirements of the design drawing; if additional requirements are specified for the procedure, and the dimension shall meet the procedure dimension requirements.
3.2.2 Raw materials (such as steel plates and profile steel) and welding materials (such as electrodes, welding wires, fluxes and protective gases) of welding parts entering the factory shall not be used until passing the inspection based on the material standards.
3.2.3 Raw materials and welding materials with unclear grades and no qualification certificate shall be inspected and identified in accordance with relevant standards to confirm their grades, compositions and properties before they can be used.
3.2.4 The shape deviation of steel shall comply with the relevant national standards and metallurgical professional standards before cutting; otherwise, it shall be corrected to meet the requirements. When corrected, the scar depth shall be less than 0.5mm for steel plate, and less than 1mm for profile steel.
3.3 Requirements for parts before welding
3.3.1 Limit deviation of part dimension
3.3.1.1 The limit deviation of the dimension of mechanically cutting plate parts shall meet those specified in Table 1. The limit deviation of the dimension of parts made form manual gas-cutting plates and profiles (such as angle steel, I steel and channel steel) shall meet those specified in Table 2.
Foreword i
1 Scope
2 Normative references
3 Requirements
4 Test method
5 Inspection rules
6 Marking, packaging, transportation and storage
Figure 1 Length and straightness tolerances of side/edge of plate parts
Figure 2 Perpendicularity and parallelism tolerances between the sides/edges of plate parts
Figure 3 Perpendicularity and parallelism tolerances of cutting section of profile parts
Figure 4 Unnoted tolerance for coaxiality between welding surfaces
Figure 5 Unnoted tolerance for perpendicularity and parallelism between surfaces of welding parts
Figure 6 Unnoted tolerance for symmetry between surfaces of welding parts
Figure 7 Incomplete penetration at root
Figure 8 Dimension and shape of specimens
Figure 9 Dimension and shape of specimens
Table 1 Limit deviation of the dimension of mechanically cut plate parts
Table 2 Limit deviation of the dimension of parts made from manual gas-cutting plates and profiles
Table 3 Dimension tolerance of arc-shaped part
Table 4 Limit deviation of the dimension of machined part
Table 5 Straightness and flatness tolerances of the surface of plate parts
Table 6 Straightness, flatness and perpendicularity tolerances of profile parts
Table 7 Skew tolerance of profile parts
Table 8 Perpendicularity tolerance of the surface corresponding to the cutting side/edge of plate parts and profile parts
Table 9 Limit deviation, roundness tolerance and crimping value of dimension of cylinder parts
Table 10 Cutting mark thickness of part when using gas cutting
Table 11 Mutual position offset when steel plates are butted
Table 12 Mutual position offset when profile steel is butted
Table 13 Mutual position offset when butt joints are installed and aligned
Table 14 Mutual position offset when I-beams and box beams are installed and aligned
Table 15 Mutual position offset when structures with complex sections are installed and aligned
Table 16 Mutual position offset between pipe walls when pipelines are installed and aligned
Table 17 Limit deviation of unnoted tolerance dimensions for non-machined surfaces of welding parts
Table 18 Unnoted tolerance for flatness of the plane of welding parts
Table 19 Limit deviation of angle with tolerance unnoted
Table 20 Classification requirements for external defects of welds
