Looking for boiler, pressure vessel and pressure pipe welder certification* * question set

1. Welding safety knowledge and regulations 1. Welders should take ③ safety measures when welding pressure pipes in boiler pressure windows. ①, stand directly on the weldment for welding ②, stand on the pad of insulating material, and rely on the weldment ③. The welder and the weldment are reliably insulated with insulating pads, and must not rely on the weldment 2. Welding tongs or welding torches should be handed over when welding operations are suspended in metal structures such as boilers and pressure vessels ③. ①, place it on the steel surface and cut off the power supply ②. Place it in a safe insulated place or hang it and cut off the power supply ③. Hang it 3. The handle of the welding clamp and the welding cable must be well insulated for ③. ①, Prevent the overheating of welding clamps and cables from causing fire disasters ②, Prevent overheating and scalding welders ③, Prevent welders from getting electric shock 4. Under the action of high-frequency electromagnetic fields, the human body will suffer from dizziness, fatigue, memory loss, insomnia and other neurological symptoms. This kind of damage to the human body is called ③. ①, Electrical injury ②, electric shock ③, electromagnetic field physiological damage 5. Welding operations in boilers, containers, pipes and metal structures belong to ② environment. ①, Ordinary ②, Special danger ③, Danger 6. When welding in a closed container, the welding machine must not be placed in ①. ①, inside the container ②, outside the container ③, on the ground 7. When welding and cutting operations are performed in boilers, pressure vessels, pressure pipes and relatively closed places, the lighting voltage should be ① volts. ①, 12 ②, 24 ③, 36 8. The hot ① produced by electric welding or gas welding is the main cause of fire and explosion accidents. ①, metal sparks ②, welding smoke ③, harmful gases 9. After the welding operation is completed, the site should be inspected to avoid leaving ③ burning and causing a fire. ①, Welding rod tip ②, slag ③, fire 10. When welding in boilers, pressure vessels, and pressure pipelines, there should be ③ on the outside. ①, lighting equipment ②, ventilation facilities ③, personnel supervision 11. According to GB3787-83 "Safety Technical Regulations for the Management, Use, Inspection and Maintenance of Hand-held Power Tools", class ③ power tools should be used for welding operations in pressure pipes of boilers and pressure vessels. ①, ① ②, Ⅱ ③, Ⅲ 12. During the process of lifting the workpiece, ① The working method of welding while lifting. ①, strictly prohibited ②, allowed ③, generally not used, allowed when necessary 2. Basic knowledge of boilers, pressure vessels and pressure pipelines 1. The "Interim Regulations on Safety Supervision of Boilers and Pressure Vessels" is to ensure the safe operation of boilers and pressure vessels and protect people's lives and * * The security of property is promulgated and implemented by ①. ①, State Council ②, Ministry of Labor ③, Ministry of Safety 2, "Interim Regulations on Safety Supervision of Boilers and Pressure Vessels" applies to all pressure-bearing ① and various pressure vessels with a pressure above one gauge pressure. ①, boilers ②, hoisting machinery ③, construction machinery 3, boiler and pressure vessels ①, manufacturing, installation, use, inspection, and modification must comply with the "Interim Regulations on Safety Supervision of Boilers and Pressure Vessels" and must and should meet the requirements of the corresponding "Regulations". ①, Design ②, Sales ③, Order 4. The main pressure components of the pressure vessel include ①, head (end cover), spherical shell plate of the spherical tank, heat exchanger tube plate, heat exchange tube, expansion joint, opening reinforcement plate, equipment flange, equipment main bolts above M36, manhole cover, manhole flange, manhole nozzle and nozzle and pipe flange with nominal diameter greater than or equal to 250mm. ①, barrel ②, support ③, lifting lugs 5. The main pressure components of the boiler include the drum, ③, header, convection beam tube, furnace (fire tube), smoke tube, etc. In addition, there are also pressure components such as superheater, economizer, and air preheater. ①, furnace wall ②, furnace hearth ③, water wall 6, welding materials for welding boiler pressure vessels, pressure piping pressure components, the user must establish strict storage, drying, distribution, recycling and reuse ③. 7. The heat treatment of gas cylinders must adopt ① heat treatment. Gas cylinders after heat treatment should generally not be welded. ①, overall ②, partial ③, post-heating 8. ③ welds should not be used for pressure vessel assembly welding. ①, docking ②, corner joint ③, cross 9, "Safety Technical Supervision Regulations for Steam Boilers" and "Safety Technical Supervision Regulations for Hot Water Boilers" are formulated in accordance with the relevant provisions of the "Interim Regulations on Safety Supervision of Boilers and Pressure Vessels" to ensure boilers ③, promote the development of the national economy, and protect personal safety. ①, Civilized production ②, clean appearance ③, safe operation 10. When repairing the boiler, ② Repair the pressure components when there is pressure or the temperature of the boiler water is high. ①, Yes ②, Strictly Prohibited ③, Be careful and OK 11. According to the classification of "Pressure Vessel Safety Supervision Regulations", high-pressure vessels belong to Class ③ pressure vessels. ①, 1②, 2③, 3 12. Boilers can be divided into power station boilers, ③ boilers, domestic boilers, ship boilers and locomotive boilers according to their uses. ①, Hot water ②, Fixed type ③, Industry 3. Classification, brand, chemical composition, mechanical properties, welding characteristics and post-weld heat treatment of metal materials 1. The structure of low carbon steel at room temperature is ①. ①, Ferrite + pearlite ②, pearlite ③, pearlite + cementite 2. The crack with the characteristics of transgranular cracking is ③. ①, hot crack ②, reheat crack ③, cold crack 3. During the tensile test process, the maximum tensile force per unit area when the sample is broken is called ③. ①, yield point ②, elongation ③, tensile strength 4, and the ability of steel to resist erosion by corrosive media is called ③. ①, Oxidation resistance ②, Structural stability ③, Corrosion resistance 5. Metals with face-centered cubic lattice have plasticity ②. ①, Fair ②, Good ③, Bad 6. According to experience, when the mass fraction of carbon equivalent is ①, the weldability of the steel is good and it can be welded without preheating. ①, <0.40% ②, <0.40~0.60% ③, <0.60% 7. According to the provisions of GB/T2650-1989 "Impact Test Method of Welded Joints", ① notched specimen is used as the standard. ①, V-shaped ②, U-shaped ③, Y-shaped 8. As the carbon mass fraction in the steel increases, the plasticity and toughness of the steel ②. ①, rise ②, fall ③, remain unchanged 9. The stress relief temperature of low carbon steel weldments is ② ℃. ①, 500~600 ②, 600~650 ③, 650~700 10. The "R" in steel number 16MnR means ③. ①, heat-resistant steel ②, boiler steel plate ③, pressure vessel steel plate 11, the “g” in steel number 20g indicates ②. ①, Steel plates for pressure vessels ②, steel plates for boilers ③, steel plates for multi-layer pressure vessels 12. The "HP" in the steel number HP245 indicates ①. ①, Steel plates for pressure vessels ②, steel plates for boilers ③, steel plates for welding gas cylinders 4. Type, model, grade use and storage of welding materials (rods, welding wires, fluxes and gases, etc.) 1. The quality of the storage of welding materials for boilers and pressure vessels directly affects the quality of welding. The welding materials in the welding materials warehouse must be classified, separated by brand, storage time, batch number, specification storage, and should be clearly marked, no less than ② m from the ground. ①, 0.2 ②, 0.3 ③, 0.4 2. Welding rods must be dried when used. Alkaline welding rods should be baked to ③ and kept warm for 1~2 hours. ①, 100~150℃ ②, 150~200℃ ③, 350~400℃ 3. The weld crack resistance of alkaline electrodes is better than that of acidic electrodes ③. ①, Same ②, Poor ③, Good 4. Acidic electrodes are more sensitive to rust, scale and grease than alkaline electrodes ②. ①, large ②, small ③, same 5. Flux is divided into smelting and sintering flux according to ②. ①, particle size ②, manufacturing method ③, chemical composition 6, HJ431 belongs to ③ manganese, high silicon, low fluorine type smelting flux. ①, low ②, medium ③, high 7, Q235B, 20R, 20g steel pressure vessels should be welded, ② electrode should be used. ①, J506 ②, J427 ③, A132 8. Welding rods and flux should be laid flat when baking, and the stacking height should be controlled below ① to ensure uniform heating and use moisture to eliminate. ①, 60mm ②, 100mm ③, 150mm 9. Welders should hold ③ when going to the welding material warehouse (secondary warehouse) to receive welding materials. ①, construction drawings ②, work permit ③, "welding rod usage card" 10. The low-hydrogen welding rod is baked at high temperature and placed in a low-temperature insulation tube ① for storage, and can be taken out as needed. ①, 100℃ ②, 180℃ ③, 200℃ 11. For workpieces with high requirements on weld impact toughness and toughness, ③ welding rod should be used. ①The selection of welding rods for , acidic ②, stainless steel ③, alkaline 12, carbon steel, and low alloy steel is usually based on its ① grade, structural rigidity, working conditions, etc. The corresponding grade of welding rod is selected. ①, strength ②, thickness ③, weld quality requirements 5. Types, names, use and maintenance of welding equipment, tools and measuring instruments 1. After the welding power supply is connected to the power grid and the output end is not connected to a load (the welding current is zero), the voltage at the output end is called ②. ①, short-circuit voltage ②, no-load voltage ③, working voltage 2, the ratio of the duration of the welding machine load operation to the full cycle time is called ②. It is a parameter indicating the working status of the welding machine. ①, rated welding current ②, load duration ③, arc voltage 3, the structure of the BX1-330 AC welding machine belongs to type ①. ①, moving iron core type ②, moving coil type ③, thyristor type 4, MZ-1000 type welding machine is ③ welding machine. ①, electroslag welding ②, argon arc welding ③, submerged arc automatic welding 5, LGK-300 model welding machine is ②. ①, Tungsten arc welding machine ②, air plasma arc cutting machine ③, CO2 gas shielded welding machine 6, welding torch model H01-6, where "1" means ②. ①, isobaric type ②, jet-suction type ③, manual 7, NBC-400 welding machine is ①. ①, CO2 semi-automatic gas shielded welding machine ②, submerged arc automatic welding machine ③, argon arc welding machine 8. According to the regulations of GB4842, the purity of argon gas used for tungsten argon arc welding should be greater than or equal to ③. ①, 99.95% ②, 98.00% ③, 99.99% 9. When the submerged arc automatic welding machine uses a DC power supply, the arc stability is good. If a DC power supply is used, ① is generally used. ①, Reverse connection method ②, Forward connection method ③, Y connection method 10. Poor contact between the cable and the weldment during welding can cause ③. ①, welding machine overheating ②, voltage drop ③, welding current suddenly high and sometimes small 11. The tool used to measure the groove angle, gap, misalignment, weld width, fillet weld leg and other dimensions of the welded joint is called ③. ①, Vernier caliper ②, slide rule ③, weld inspection ruler 12. The color number of filter glass (goggles) generally suitable for welding current 100~350A is ②. ①, No. 7~8②, No. 9~10③, No. 11~12 VI. Characteristics of commonly used welding methods, welding process parameters, welding sequence, operating methods and their impact on welding quality 1. During welding, various items selected to ensure welding quality The general name of parameters (such as welding current, arc voltage, welding speed, linear energy, etc.) is called ②①, welding process ②, welding parameters ③, welding thermal cycle 2, electrode During the arc welding process, the lateral swing of the electrode is mainly to ensure the weld ③ . ①, Penetration ②, Height ③, Width 3. Increasing the welding current during submerged arc welding can speed up the melting speed of the welding wire, and increase the melting amount and penetration depth of the base metal ①. ①, increase ②, decrease ③, remain unchanged 4. The welding voltage of submerged arc welding is proportional to the arc length. As the voltage increases, the arc length increases. ； As the voltage decreases, the arc length shortens. ①, direct proportion ②, inverse proportion ③, irrelevant 5. If hydrogen elimination treatment or post-weld heat treatment is adopted after welding, it will help to prevent the formation of weld seam ②. ①, hot cracks ②, cold cracks ③, pores 6, and ③ in the welding arc zone have the highest temperature, so the arc voltage should be as low as possible during welding to avoid a large amount of heat being radiated. ①, Cathode area ②, Anode area ③, Arc column 7. According to JB/T4709-2000 "Steel Pressure Vessel Welding Regulations" in the welding environment, when the relative temperature is greater than ②, effective protective measures must be taken, otherwise welding is prohibited. ①, 80% ②, 90% ③, 95% 8. When using gas welding to weld non-ferrous metals, cast iron, stainless steel and other materials, in order to ensure the welding quality, ② that can remove oxides and other impurities must be used. ①, flux ②, flux ③, slag 9, thick plate electrode arc welding. In order to fill the groove during welding, multi-layer welding or multi-layer multi-pass welding must be used. In order to reduce deformation, which welding sequence method in the figure below is correct① 7 8 9 5 6 1 2 3 4 10 11 12 (a) 4 5 6 2 3 1 7 8 9 10 11 12 (b) 3 11 12 2 10 1 4 7 5 9 8 6 (c) ①, (a) ②, (b) ③, (c) 10. When welding aluminum and its alloys with tungsten electrode and argon arc welding, ③ power supply should be used. ①, DC pulse ②, DC forward connection ③, AC 11. When performing positioning welding, the weld length and simple distance are mainly determined based on ③. ①, electrode diameter ②, welding current ③, workpiece thickness and structural shape 12. Welding arc ② will cause the arc to swing violently, increase spatter, and reduce the stability of the arc. ①, too short ②, too long ③, too small 7. Weld form, joint form, groove form, weld symbol and pattern identification 1. Welds are divided into butt welds according to different combination forms, ②, end welds, plug welds, groove welds and combination welds of butt and fillet welds. ①, I-shaped weld ②, corner weld ③, back cover weld 2, butt weld beveling is to ensure penetration and good weld formation and internality ②. ①, strength ②, quality ③, plasticity 3, and the choice of groove form mainly depends on the plate ①, welding method and process and economic rationality. ①, thickness ②, quality ③, mechanical properties 4, groove processing ②, such as flatness, straightness, dimensional accuracy, etc., all affect the quality of the weld. ①, Method ②, Quality ③, Working hours 5, U-shaped, double-sided U-shaped, and U-shaped grooves with blunt edges of large plates can be processed by ②. ①, Shearing machine ②, Planing machine ③, Lathe 6. When the weld symbol marked on the drawing (as shown below), it means ②. ①, There are fillet welds on three sides of the workpiece ②, Fillet welds welded around the workpiece on site ③, Fillet welds welded on site 7. The weld size symbol indicating the size of the welding leg, its symbol is ③. ①, A ②, B ③, K 8. The bevel size symbol indicating the depth of the bevel is represented by the symbol ①. ①, H ②, Y ③, Z 9. In the GB324-88 "Weld Symbol Representation" standard, the basic symbol for welds is ②. ①, Single-sided V-shaped weld with blunt edge ②, Single-sided V-shaped weld ③, V-shaped weld with blunt edge 10. When the weld auxiliary symbol marked on the drawing is , its meaning is ③ . ①, fillet weld ②, convex fillet weld ③, concave fillet weld 11. When the weld auxiliary symbol marked on the drawing is , its meaning is ③. ①, V-shaped weld at the back cover ②, V-shaped weld at the flat surface ③, V-shaped weld at the flat back cover 12. When butt welding steel plates of different thicknesses, the purpose of thinning the thick plate is mainly to avoid the joint ③. ①, produce large deformation ②, produce serious welding defects ③, cause large stress concentration 8. Performance of welded joints and their influencing factors 1. The gas that has the greatest impact on the performance of the weld in the arc zone is ①. ①, N2, O2, H2 ②, CO, CO2 ③, C, Ar 2, hydrogen embrittlement, white spots, microscopic spots and delayed cracks are all caused by the action of ① in the welding gap. ①, hydrogen ②, nitrogen ③, oxygen 3, the element or iron alloy used for deoxidation is called ③. ①, alloy agent ②, arc stabilizing agent ③, deoxidizer 4, low temperature steel welding, the purpose of controlling the interpass temperature (or interlayer temperature) is ③. ①, Prevent the generation of hardened structure ②, Prevent weld metal segregation ③, Prevent overheated grain growth 5. When austenitic stainless steel is welded with the same welding material as the base metal, the primary crystallization structure of the weld seam is ①. ①, austenite ②, ferrite ③, pearlite 6. Welding materials affect the chemical composition and structure of the weld, and therefore also affect the ① of the weld. ①, Performance ②, Forming ③, Size 7. The welding heat-affected zone of low carbon steel and low alloy steel that is not easy to quench can be divided into ② zones according to the structural characteristics. ①, 2 ②, 4 ③, 6 8. The main purpose of solid solution or stabilization heat treatment after welding of austenitic stainless steel is ②. ①, eliminate hydrogen ②, prevent intergranular corrosion ③, improve mechanical properties 9. As the welding line energy (or heat input) increases, the heat affected zone ②. ①, narrowed ②, widened ③, unchanged width 10. Among the following welding methods, the method to obtain a narrower heat affected zone by concentrating arc heat is ②. ①, electrode arc welding ②, tungsten argon arc welding ③, submerged arc automatic welding 11. For welding of aluminum, titanium, copper and their alloys, ① should be selected to obtain reliable weld quality. ①, Tungsten arc welding ②, electrode arc welding ③, submerged arc automatic welding 12. The segregation phenomenon of welds generally refers to ③. ①, Non-uniformity of weld grain size ②, Non-uniformity of weld metal structure and properties ③, Non-uniform distribution of alloy elements in weld metal 9. Causes, hazards, prevention methods and repairs of welding defects 1. Electrode arc welding cover welding has fast welding speed, large welding current, improper electrode inclination angle, etc. can also easily cause ② defects. ①, Weld reinforcement is too high ②, undercut ③, weld width is too wide 2, pressure vessels that do not allow undercut are ②. ①, Mild steel separation vessel ②, low temperature pressure vessel ③, 16MnR steel pressure vessel 3. The cause of cold shrinkage holes is ①. ①. During the penetration welding method, due to the rapid cooling and shrinkage of the arc-extinguishing molten pool ②, the eccentricity of the welding rod ③, and the large amount of gas dissolved in the molten pool that escapes during crystallization and solidification 4. Appropriately increasing the preheating temperature and heat input (or linear energy) can reduce the deformation rate of the weld metal, thus ① the tendency of crystallization cracks. ①, reduce ②, increase ③, will not affect 5. The reason for insufficient penetration is ①. ①, The reasons for incomplete root cleaning on the back side during double-sided welding ②, small blunt edge size ③, large welding current 6, and undercut defects in submerged arc welding seams are ①. ①, The welding speed is too fast ②, the welding speed is slow ③, the welding current is too small 7. The tungsten inclusion in the weld is caused by ②. ①, The shielding gas flow is small ②, the arc is started by the contact method ③, the tungsten electrode diameter is too large 8. The reason for the slag inclusion defect during the electrode arc welding process is ②. ①, The blunt edge of the groove is small ②, the welding speed is too slow, the slag is advanced ③, the base metal is overheated 9. ① It is easy to cause welding defects in the weld seam during the gas welding process. ①, The flame energy rate is large ②, the welding speed is too fast ③, the welding pool area is too small 10. Among various welding defects, ① is the most harmful. ①, cracks ②, pores ③, slag inclusions 1, ③ Carbon arc gouging is not suitable. ①, Carbon steel ②, Stainless steel ③, Easy-quenching steel 12. The pores are caused by the gas in the molten pool being hindered during the crystallization process of the molten pool and unable to escape and remaining in the weld. The prevention measures are ③. ①, Select the correct bevel angle and blunt edge ②, increase the welding current ③, remove rust, oil, and moisture from the bevel and welding wire, and dry the welding rod and flux. 10. Weld appearance inspection methods and requirements, non-destructive testing method characteristics, scope of application, level, signs and defect identification 1. The commonly used method to detect internal defects of welds is ③. ①, 5x magnifying glass observation method ②, magnetic particle flaw detection method ③, radiographic flaw detection method 2. The "new examination regulations" for welding examination stipulate that the standard for radiographic transillumination of the test piece weld is ②. ①, GB3323-87 ②, JB4730-94 ③, DL/T5069 3. The "new examination regulations" for welder examination stipulate that when the test piece weld seam is radiographed, the weld defect grade is not lower than ② level to be qualified. ①, Ⅰ ②, Ⅱ ③, Ⅲ 4. Magnetic particle flaw detection method is mainly used to detect ② defects in welds. ①, surface ②, surface and near surface ③, internal 5. Penetrant flaw detection method is mainly used to detect ① defects in welds. ①, surface ②, surface and near surface ③, interior 6. The defect of the weld in the radiographic film shown below is ②. ①, porosity ②, slag inclusion ③, undercut 7. When the ultrasonic flaw detection method is used to detect the weld seam of the test piece, its main function is ③. ①, Thickness measurement ②, cleaning welds ③, detecting internal defects of welds 8. "Safety Technical Supervision Regulations for Pressure Vessels" stipulates that butt joint welds of Class III vessels should be subject to ③ flaw detection. ①, 20% ②, 50% ③, 100% 9. For steel types with a tendency of delayed cracking, non-destructive testing should be carried out ② hours after welding is completed. ①, 12 ②, 24 ③, 48 10. The "Pressure Vessel Safety Technical Supervision Regulations" stipulates that defects at the same position must not be repaired more than ② times. ①, 1②, 2③, 3 11. The defect of the weld in the radiographic film shown below is ①. ①, porosity ②, slag inclusion ③, undercut 12, radiographic flaw detection has the highest sensitivity for defect detection inside the weld ①. ①, Circular pores ②, micro cracks ③, linear defects 11. Causes and prevention methods of welding stress and deformation 1. The stress that still exists in the object after all external loads are removed is usually called ③. ①, working stress ②, temperature stress ③, residual stress 2, and the welding deformation shown in the figure below belongs to ③. ①, bending deformation ②, twisting deformation ③, wave deformation 3. The welding deformation shown in the figure below belongs to ②. ①, Bending deformation ②, twisting deformation ③, wave deformation 4. The methods of correcting welding deformation can be divided into two categories: mechanical correction method and ① correction method. ①, flame heating ②, hammering ③, heat treatment 5, using rigid fixation method for welding, ① will increase. ①, Welding stress ②, welding deformation ③, weld plasticity 6, and misaligned edges will cause ① and reduce the effective plate thickness, thereby reducing the structural strength or load-bearing capacity. ①, Stress concentration ②, stress uniformization ③, stress attenuation 7. As the linear energy (or heat input) increases, the width of the heating zone increases, and the thermal compression plastic deformation zone also increases, thus resulting in welding residual deformation ②. ①, decrease ②, increase ③, remain unchanged 8. The butt weld adopts groove ③, and the welding deformation is small. ①, V-shaped groove ②, U-shaped groove ③, double-sided V-shaped groove 9. Among the following statements, ② is correct. ①, The size of the weld seam has no effect on the welding deformation ②. Appropriately reducing the size of the weld seam can reduce the welding deformation ③. Appropriately increasing the size of the weld seam can reduce the welding deformation 10. The most common deformation caused by thin plate welding is ①. ①, Wave deformation ②, angular deformation ③, bending deformation 11. Select a reasonable assembly and welding sequence to reduce welding stress, including ①. ①. When assembling panels, staggered short welds should be welded first, and then the straight long welds should be welded by the segmented back welding method. 2. When assembling panels, the straight long welds should be welded first, and then the short welds. 3. When assembling panels, any place can be welded first. 12. When assembling and welding the cylinder and the head as shown in the figure below, the deformation that is usually easily produced is 1. Head ①, misalignment deformation ②, twisted deformation cylinder ③, bending deformation 12, basic knowledge of welding quality management system, rules and regulations, process disciplines, welding process assessment, welder examination and management rules 1. The welding process card is a welding process document directly sent to ① to guide production. ①, welder ②, team leader ③, workshop director 2. The welding process factors in JB4708-2000 "Steel Pressure Vessel Welding Process Qualification" are divided into ③ factors. ①, 1 ②, 2 ③, 3 3. The bending test in JB4708-2000 "Welding Procedure Qualification of Steel Pressure Vessels" stipulates that the bending center diameter is ③ times the plate thickness. ①, 2 ②, 3 ③, 4 4. Boiler and pressure vessel quality management system is a unit engaged in boiler, pressure vessel and pressure piping ①. In order to ensure that product quality complies with regulations, standards and designs, and meets contract and customer requirements, in accordance with GB/T19000 "Quality Management System, Basics, Terminology" and other series of standards, combined with the actual situation of the unit, a system is established to implement quality in the entire process of manufacturing and installation. ①, Manufacturing, installation ②, use ③, construction 5. According to the "Safety Technical Supervision Regulations for Pressure Vessels", the product welding test plate of the longitudinal welding joint of the cylindrical pressure vessel ① is used as an extension of the longitudinal welding joint of the cylinder section, and is continuously welded using the same conditions and welding processes used for welding pressure vessels. ①, should ②, should not ③, if the operation is inconvenient, it may not be performed. 6. The bending test in the "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" stipulates that the bending axis diameter is ② times the plate thickness (excluding friction welding and surfacing welding). ①, 2 ②, 3 ③, 4 7. "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" test piece form, position and code. The code 6G represents the test piece position is ③. ①, vertical fixation ②, horizontal fixation (upward welding) ③, 45° fixation (upward welding) 8. According to the "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules", the defects that are not allowed to exist in the surface defects of the welder examination test piece are ①. ①, Inadequate penetration ②, Undercut ③, Pits on the back 9. After welding, ① the welder will remove the slag, spatter, etc. on the surface of the weld, conduct self-inspection, and submit it for inspection after passing the test. ①, should be serious ②, should not be ③, casual 10. The "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" were issued by ③. ①, State Council②, * * Economic Planning Commission ③, * * General Administration of Quality Supervision, Inspection and Quarantine 11. The "Interim Regulations on Safety Supervision of Boilers and Pressure Vessels" must be implemented ③ : The "Safety Technical Supervision Regulations for Steam Boilers", "Safety Technical Supervision Regulations for Hot Water Boilers" and "Safety Technical Supervision Regulations for Pressure Vessels" are safety technical regulations that must be implemented. ①, Document ②, Regulation ③, Regulation 12, "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" are formulated in accordance with the "Interim Regulations on Safety Supervision of Boiler and Pressure Vessel" in order to improve the quality of welders and strengthen the management of welders to ensure the welding quality of boiler and pressure vessels and ②. ①, Welded structure ②, pressure pipeline ③, steel structure (2) Basic knowledge corresponding to various welding methods (1), electrode arc welding test question set: 1. The metal shell of the welding equipment must ② be grounded or connected to zero. ①, Together with other equipment ②, Independently and reliably ③, Together with the secondary coil 2. Welding and repairing oil tanks, tankers, containers that have stored flammable gases and flammable liquids, and the auxiliary equipment connected together are classified as Class ① fire. ①, 1②, 2③, 33. In order to prevent fire and explosion accidents caused by welding and cutting operations, ① should be placed at the work site. ①, fire-fighting equipment ②, ventilation device ③, dust removal equipment 4. In medium and low pressure containers, ① is a weak part in the container and should be reinforced. ①, Opening ②, Flange ③, Support 5. According to the provisions of JB4708-2000 "Steel Pressure Vessel Welding Process Qualification", the welding process for qualified plate butt weld test pieces is ② butt weld of pipe, and vice versa. ①, Not applicable to ②, Applicable to ③, Applicable to large diameter 6. Boilers can be divided into low-pressure boilers, medium-pressure boilers, high-pressure boilers ② boilers and subcritical pressure boilers according to outlet medium pressure. ①, normal pressure ②, ultra-high pressure ③, micro pressure 7, the main reason why austenitic stainless steel uses ultra-low carbon welding wire for welding is ①. ①, Prevent intergranular corrosion ②, Prevent hot cracks ③, Prevent pores 8. During the hydraulic pressure test, the ambient temperature should be higher than ②. ①, 0℃ ②, 5℃ ③, 15℃ 9. The corresponding brand of model E5015 welding rod is ③. ①, J502 ②, J506 ③, J507 10, 1Cr18Ni9Ti steel welding, ③ grade electrode should be used. ①, A102 ②, A107 ③, A132 11. The low hydrogen content in the weld metal of low-hydrogen welding rods is mainly due to ①. ①, The coating contains CaF2 ②, The drying temperature of the welding rod is high ③, The coating contains carbonate 12. The DC arc welding generator reversal is caused by ③. ①, Grid voltage fluctuation ②, one phase of the three-phase power supply is open circuit ③, the three-phase line of the power supply is out of phase 13. Arc voltage during arc welding of the electrode ③ The no-load voltage of the arc welding power supply. ①, equal to ②, greater than ③, less than 14. The selection of electrode arc welding power source and welding cable should be based on the ① of the welding machine. ①, rated welding current ②, welding current ③, short-circuit current 15. DC welding machines use acidic electrodes to weld thicker steel plates, and it is advisable to take ② to obtain greater penetration. ①, Reverse polarity connection method ②, Positive polarity connection method ③, Arc jump welding method 16. When single-sided welding and double-sided forming are required, and when welding flat butt joints in the horizontal position for bottom welding, use φ3.2 electrodes, and the selected welding current is ② A. ①, 30~60 ②, 80~110 ③, 140~180 17. The welding method in which the base metal to be welded is heated and melted to form a weld is called ①. ①, Welding ②, Pressure welding ③, Brazing 18. When the butt joints of steel plates of different thicknesses do not need to be thinned according to relevant regulations, the basic form and size of the groove shall be selected according to ③. ①, Dimensional data of the thinner plate ②, Dimensional data of the average thickness of the two plates ③, Dimensional data of the thicker plate 19. The function of the blunt edge of the groove is to prevent ②, but the blunt edge size should also ensure that the first layer can be welded through. ①, Not penetrated ②, Burned through ③, Not fused 20, Easy to quench steel welding, the process measures of preheating before welding, controlling inter-pass temperature (or inter-pass temperature) and post-weld slow cooling or post-weld heat treatment are often used. The main purpose is ①. ①, Prevent the generation of hardened structure ②, improve weld formation ③, improve working conditions 21. The segregation of sulfur and phosphorus in the weld is easy to cause ①. ①, hot cracks ②, cold cracks ③, reheat cracks 22. In the heat-affected zone of steel that is not easily quenched, the area with coarse grains is ①. ①, overheating zone ②, normalizing zone ③, blue crisp zone 23. When the carbon arc gouging speed is too fast, ①. ①, The depth of the gouge decreases ②, the width of the gouge increases ③, the size of the gouge increases 24. The slag remaining in the weld after welding is called slag inclusion. The preventive measures include ②. ①, Preheat the workpiece ②, thoroughly clean the groove surface and interlayer welds ③, choose a reasonable welding sequence and direction 25. Cut samples from the weldment or test piece, or test the product (or analog body) as a whole to check its various mechanical properties. The test method is called ③. ①, Non-destructive test ②, Sealing test ③, Destructive test 26. Macro-metallography is a test method that uses the naked eye or ① to inspect the macro structure and macro defects of metallographic samples. ①, magnifying glass ②, flat mirror ③, optical microscope 27. "Steam Boiler Safety Supervision Regulations" stipulates that defects at the same position should not be repaired more than ③ times. ①, one ②, two ③, three 28. The workpiece welding shown in the figure below mainly produces ②. ①, angular deformation ②, longitudinal shrinkage deformation ③, transverse shrinkage deformation 29. As shown in the figure below for panel welding, the most reasonable welding sequence to reduce welding stress is ②. 2 3 ①, 3-2-1 1 1 ②, 1-2-3 2 3 ③, 1-3-2 30. The welding sequence of the segmented desoldering method is ③. abcd ①, abcd ②, acbd ③, dcba 31. The welding quality inspection of boiler and pressure vessels is mainly divided into ③, inspection during the welding process and post-welding inspection. ①, Steel quality inspection ②, finished product inspection ③, pre-welding inspection 32. In the "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" welding methods and codes, the SMAW representative welding method is ①. ①, Electrode arc welding ②, Gas tungsten arc welding ③, Submerged arc welding 33. "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" butt weld test piece without liner of low alloy steel and alloy steel bending angle is ① (except for friction welding and surfacing welding). ①, 50° ②, 90° ③, 180° 34. The metal welding arc is ③ the conductive phenomenon through the gas space between the welding rod and the weldment. ①, voltage ②, current ③, charge 35, the overall efficiency of the inverter arc welding rectifier can reach ③. ①, 50% ②, 70% ③, 85% 36. The main function of the welding rod coating is ③. ①, remove oil and rust at the groove of the workpiece ②, reduce the deformation of the workpiece ③, improve the process performance of the welding rod, protect the weld metal and metallurgical treatment effect 37. When welding the filter layer of the stainless steel composite steel plate, the ① method is generally used. ①, Welding rod arc welding ②, submerged arc welding ③, CO2 gas shielded welding 38. When baking the welding rod, the temperature should be gradually heated. Do not put it directly into the heated box for baking, because the welding rod suddenly encounters high temperature and can easily cause ②. ①, coating failure ② , coating rupture ③ , difficulty in arc ignition of the electrode 39. The characteristic curve of the arc welding machine drops sharply, indicating that when the arc length changes, the welding current changes ② . ①, very large ②, very small ③, no change 40. The protection method used in arc welding for the welding area is ③. ①, gas protection ②, slag protection ③, gas-slag combined protection 41. In the three pictures below, the magnetic deflection blow caused by ferromagnets is ①. Welding rod coating eccentricity (a) (b) (c) ①, (a) ②, (b) ③, (c) 42. When assembling stainless steel composite steel, the positioning welding must be on the ① surface. ①, base layer ②, transition layer ③, clad layer 43, and electrode arc welding, in order to increase the penetration depth of the weld, the measures are ①. ①, increase the welding current ②, the smaller the better ③, reduce the groove angle 44. The heat-affected zone of the welded joint has a great influence on the performance of the joint, therefore, the heat-affected zone ②. ①, The bigger the better ②, The smaller the better ③, The sizes are all the same 45. When welding steel grades 20g, 20R, 20 (forged) with arc welding rods, the grade of the welding rod selected is ①. ①, J427 ②, J422 ③, J507 46. Welding rod arc welding usually determines the type of welding power source according to ③. ①, the composition of the weldment ②, the structure of the weldment ③, the type of electrode coating 47, ① is the most important process parameter of electrode arc welding, and is one of the parameters that needs to be adjusted during the welder's operation. ①, welding current ②, arc voltage ③, electrode diameter 48, the welding crack produced when the welding joint cools to a lower temperature is called ②. ①, hot cracks ②, cold cracks ③, reheat cracks 49. The appearance of white spots in the weld will cause the weld metal to ③ * * decline. ①, toughness ②, hardness ③, plasticity 50, ① is one of the main factors causing pores and cold cracks in welded joints. ①, hydrogen ②, nitrogen ③, argon 51, and the fracture inspection of pipe welding joints is very sensitive to ②. ①, pores ②, unfused ③, slag inclusion 52. Welds requiring good plasticity and high impact toughness should use ② electrodes. ①, Acidic ②, Alkaline ③, Stainless Steel 53. When transporting the electrode during arc welding, there are three basic actions - feeding the electrode (maintaining the arc length), advancing along the welding direction and ②. ①, Longitudinal swing ②, Horizontal swing ③, Wave swing 54. The "dangerous temperature zone" where stainless steel produces intergranular corrosion refers to ③. ①, 200~450℃ ②, 550~650℃ ③, 450~850℃ 55. The three factors that cause cold cracks in welds are: (a) Large residual stress ； (b), the role of hydrogen ； (c). There is a hardened structure in the weld. Therefore, the main preventive measures are ③. ①, Reduce the sulfur and phosphorus content of the base metal and the welding rod ②, increase the manganese content of the welding rod ③, use low hydrogen welding rods, preheat before welding, and anneal after welding. 56. The following three types of weld joints (long welds that cannot be welded continuously at one time due to the limited length of the welding rod) belong to the segmented back welding method ②. Head 1 Tail Head 2 Tail Head 2 Tail Head 1 Tail Head 1 Tail Tail 2 Head (a) (b) (c) ①, (a) ②, (b) ③, (C) 57. The value of the alternating current measured with an ammeter is the value of the alternating current ①. ①, effective ②, instantaneous ③, average 58, transformers are all working ②. ①, Lenz's law ②, electromagnetic induction principle ③, Ohm's law 59. When repairing cast iron by cold welding, ① welding rod is often used. ①, Z308 ②, J502 ③, R207 60, BX3-300 AC welding machine structure belongs to type ②. ①, Moving iron core type ②, Moving coil type ③, Tap type (2) Gas tungsten arc welding test question set 1. Oxygen pressure changes with the rise and fall of temperature. When the oxygen bottle ③, it will cause the pressure inside the bottle to increase and cause an explosion. ①, exposed to rain②, close to wind source ③, close to heat source, exposed to the sun 2. When you find someone getting an electric shock, you should first ②. ①. Pull up the person who received an electric shock with your hands. ②. Cut off the power immediately. ③. Immediately perform artificial respiration. 3. Installation and maintenance of welding equipment should be done by ③. ①, welder ②, instrument worker ③, electrician 4, ① structure is the most ideal structural shape in pressure vessels. ①, Spherical ②, Cylindrical ③, Conical 5. Pressure vessels can be divided into normal temperature vessels, high temperature vessels and low temperature vessels according to the design temperature. The design temperature is equal to or lower than ② ℃. ①, —10 ②, —20 ③, —30 6. According to the provisions of JB4708-2000 "Welding Process Qualification of Steel Pressure Vessels", the important factors are the welding process factors that affect the welded joint ①. ①, tensile strength and bending properties ②, impact toughness ③, hardness 7, steel grade 20g represented by 20 ②. ①, yield point value ②, average carbon mass fraction 20/10,000 ③, average carbon mass fraction 28%, when welding austenitic stainless steel, the welds in contact with corrosive media must be ③ welded. ①, first ②, middle ③, last 9. During the hydraulic pressure test, ② a pressure gauge that has been calibrated regularly should be installed. ①, one ②, two ③, three 10. The surface quality of the welding wire, such as diameter deviation, surface hardness uniformity, presence of grease, rust, etc. will affect the stability of ① and the quality of the weld. ①, Welding process ②, arc combustion ③, melt transition 11, 12CrMo, 12CrMoG steel welding, ② brand electrode should be used. ①, J427 ②, R207 ③, R507 12. 1Cr18Ni9Ti austenitic stainless steel and Q235-B low carbon steel are welded by manual tungsten arc welding. If no filler wire is added, ① structure will inevitably appear in the weld. ①, martensite ②, pearlite ③, austenite 13. The no-load voltage of my country's electrode arc welding DC arc welding power supply is ② volts. ①, 220 ②, 50~90 ③, 24~36 14. Argon, the protective gas for argon arc welding, is a ① gas. ①, Inert ②, Oxidizing ③, Reducing 15. The electrode coating turns red during the welding process, indicating the welding current ①. ①, Too big ②, Too small ③, Moderate 16. When using alkaline welding rods, generally use ① arc ignition, otherwise pores are likely to occur in the arc ignition area. ①, scratch method ②, impact method ③, reverse connection method 17. According to GB324-88 "Weld Symbol Representation Method", the function of the weld symbol is ①. ①, Simplify the welds on the drawing ②, indicate the weld size ③, indicate the welding specifications 18. GB985-88 is about the weld grooves of carbon steel, low alloy steel gas welding, manual arc welding and gas shielded welding ①. ①, Basic form and size ②, Name ③, Purpose 19. The function of the groove assembly gap is mainly to ensure the root ②. ①, forming ②, welding penetration ③, weld height 20. In the affected area of ​​​​hard-hardened steel, the area with the best comprehensive mechanical properties is ②. ①, overheating zone ②, normalizing zone ③, recrystallization zone 21. The interaction between oxygen and metal during welding mainly makes the metal ①. ①, Oxidation ②, Reduction ③, Ionization 22. The oxides generated by the oxidation of certain metals (such as AI, Mg, etc.) are insoluble in the metal and float on the surface of the molten pool in the form of thin films or particles, so it is easy to cause ③. ①, pores ②, poor forming ③, impurities 23, oil, rust, slag and other contaminants on the groove surface or front layer weld surface can also easily cause ① and defects such as pores and slag inclusions. ①, not fused ②, welding flash ③, weld is too thick or too high 24. The undercut part of the weld will easily cause ① at the joint. ①, stress concentration ②, slag inclusion ③, and dirt accumulation 25. ③ Carbon rods are often used for large-area planing or planing. ①, copper-plated solid round ②, copper-plated hollow round ③, copper-plated solid flat 26. Pressure resistance test can be divided into ② types according to the test medium. ①, 1 ②, 2 ③, 3 27. During radiographic flaw detection, the most appropriate protection method for personnel is ③. ①, Standing next to the X-ray machine ②, Standing one meter in front of the X-ray machine ③, Standing in a shielded place outside the safe range 28. The workpiece welding shown in the figure below mainly produces ③. ①, angular deformation ②, longitudinal shrinkage deformation ③, transverse shrinkage deformation 29. The legal measurement unit of stress is ③. ①, kgf/mm2 (kilogram force/mm2) ②, 1b/in2 (pounds per square inch) ③, N/mm2 or Mpa (N/mm2 or MPa) 30. When welding is heated, the weldment cannot expand freely, and when cooled, the weldment cannot shrink freely, then the weldment after welding ③. ①, there is welding stress, there is no welding deformation ② , there is welding deformation, there is no welding stress ③ , there is welding residual stress and residual deformation. 31. In the "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules", metallographic inspection (macroscopic) of tube-sheet corner joints requires ③ inspection surfaces of any test piece to be inspected. ①, 1 ②, 2 ③, 3 32. According to the "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules", the welding operation skills examination venue should meet the welder examination requirements, and there should be no less than ③ examination stations, which should include at least three welding methods: electrode arc welding, gas shielded welding, and submerged arc welding. ①, 3 ②, 8 ③, 10 33. If the nozzle diameter of the manual tungsten arc welding gun and the argon gas flow rate increase at the same time, the protection effect will be ③. ①, weakened ②, unchanged ③, increased 34. When welding with tungsten argon arc welding, if the argon gas flow is too low, the air flow stiffness is poor, the ability to remove the surrounding air is weak, and the protection effect is not good. ； On the contrary, if the flow rate is too large, it will easily become turbulent flow and entrain air, which will also reduce the protection effect. Select according to empirical formula: Q=KD(Q: Argon gas flow, L/min, D: Nozzle hole diameter, mm,) K: The coefficient is generally selected ②. ①, 0.2~0.4 ②, 0.8~1.2 (upper limit for large nozzles, lower limit for small nozzles) ③, 2~3 35. According to JB/T4709-2000 "Steel Pressure Vessel Welding Regulations" in the welding environment, when the gas protection wind speed is greater than ①, effective protective measures must be taken, otherwise welding is prohibited. ①, 2m/s ②, 4m/s ③, 8m/s 36. Pulse argon arc welding can control the type and penetration depth of the molten pool by adjusting pulse frequency, pulse width ratio, pulse current, base current and other parameters, so it is especially suitable for all-position welding and ① and heat-sensitive materials. ①, thin plate ②, thick plate ③, thick metal structural parts 37. When welding 0Cr18Ni9Ti and 1Cr18Ni9Ti stainless steel by tungsten arc welding, the steel number of argon arc welding wire selected is ②. ①, H08Mn2SiA ②, H0Cr21Ni10Ti ③, H10MnSi 38. The main function of the high-voltage pulse circuit of the argon arc welding machine is ②. ①, Reduce spatter ②. Arc ignition, arc stabilization (for AC argon arc welding machine) ③. Increase heat 39. There are three types of tungsten electrodes for manual tungsten argon arc welding: pure tungsten electrode, thoriated tungsten electrode and cerium tungsten electrode. Currently, ③ is commonly used. ①, pure tungsten electrode ②, thoriated tungsten electrode ③, cerium tungsten electrode 40, tungsten electrode argon arc welding, the ① method should be used when the arc is extinguished. ①, current weakening ②, reflow ③, repeated arc interruption 41. Steel pressure vessels must pass 100% ③ before conducting air pressure tests. ①, Ultrasonic flaw detection ②, Magnetic particle flaw detection ③, X-ray flaw detection 42. When welding thin plate butt parts with a thickness of 0.3mm, ② welding method should be used. ①, Electrode arc welding ②, Manual tungsten pulse argon arc welding ③, CO2 gas shielded welding 43. When the welding speed increases when manual tungsten argon arc welding, the protection effect ③. ①, increase ②, remain unchanged ③, weaken 44. Among the following characteristics of manual tungsten arc welding, it is incorrect ③. ①, the arc is easy to control ②, the cost is high ③, and the production efficiency is high 45. When the welding gun of manual tungsten arc welding uses an air-cooled welding gun, the welding current should generally not be greater than ② A. ①, 50 ②, 100 ③, 200 46. In the manual tungsten argon arc welding equipment system, the water supply system is used for ②. ①, cooling the workpiece ②, cooling the welding gun ③, controlling the welding heat input 47. When manual tungsten electrode argon arc welding uses AC power supply, it is advisable to use a tungsten electrode with a ③ end. ①, pointed conical shape ②, flat pointed conical shape ③, spherical shape 48. When manual tungsten electrode argon arc welding, ③ has the worst gas protection effect. ①, Butt joint ②, T-shaped joint ③, Lap joint 49, When welding stainless steel by manual tungsten arc welding, the protection effect is the worst when the weld surface is ③. ①, golden yellow ②, gray ③, black 50. The butt weld of the stainless steel plate in the picture below has been tested by penetrant testing, and ① is found to be a defect. ①, Longitudinal cracks ②, transverse cracks ③, dendritic cracks 51. The fillet weld of the stainless steel plate in the picture below has been tested by penetrant testing, and ① is found to be a defect. ①, needle-like micropores ②, transverse cracks ③, undercut 52. The butt weld of the carbon steel plate in the picture below has been inspected by penetrant flaw detection, and ② is found to be a defect. ①, Longitudinal crack ②, transverse crack ③, dendritic crack 53. The function of the high-frequency oscillator of the DC tungsten arc welding machine is ①. ①, arc starting ②, arc stabilization ③, reducing spatter 54. The melting electrode argon arc welding machine is composed of welding current, ②, water cooling system, control system, wire feeding mechanism and semi-automatic welding torch. ①, pulse circuit ②, gas supply system ③, high-frequency oscillator 55, tungsten electrode argon arc welding when welding carbon steel, alloy steel, and stainless steel should use DC power supply ① polarity. ①, forward ②, reverse ③, forward or reverse 56. When the welding current of tungsten electrode argon arc welding exceeds the allowable current of the tungsten electrode, it will cause the tungsten electrode to overheat and evaporate, affecting arc stability and causing ① defects in the weld. ①, clamped tungsten ②, pores ③, incomplete welding 57, the type and polarity of the power source for argon arc welding need to be selected according to ①. ①, weldment material ②, welding wire material ③, weldment thickness 58, GB324-"Weld Symbol Representation" The basic symbol for fillet welds is ①. ①, (a) ②, (b) (a) (b) (c) ③, (c) 59. GB324-"Weld Symbol Representation" The supplementary symbol indicating that there is a backing plate at the bottom of the weld is ①. ①, (a) ②, (b) (a) (b) (c) ③, (c) 60 GB324-"Weld Symbol Representation" The auxiliary symbol indicating the bulge on the weld surface is ③. ①, (a) ②, (b) (a) (b) (c) ③, (c) (3) Gas metal arc welding test question set 1. When welding in boilers, containers, and pipes, in order to enhance ventilation and prevent poisoning and heat stroke, ② can be put in. ①, hydrogen ②, cold air ③, oxygen 2, and the smoke and dust generated by arc welding are mainly harmful to the human body ③. ①, Silicon poisoning ②, Carbon poisoning ③, Welder's pneumoconiosis 3. The current frequency of the AC arc welding machine is ②, which is the most dangerous frequency for human safety. ①, 30Hz ②, 50Hz ③, 100Hz 4. According to the provisions of GB4708-2000 "Welding Procedure Qualification of Steel Pressure Vessels", the welding procedure qualification shall be carried out by ② welding test piece. ①, qualified welders ②, skilled welders in the unit ③, welding experts from outside units 5. "Pressure Vessel Safety Technical Supervision Regulations" divide the toxicity degree of pressure vessel media (ie, the maximum allowable concentration) into ① (Level I), highly hazardous (Level II), moderate hazard (Level III) and mild hazard (Level IV). ①, extreme hazard ②, severe hazard ③, four degree hazard 6. When one pulse of molten electrode pulse gas shielded welding can transfer several droplets, the droplet transfer frequency ① pulse frequency. ①, greater than ②, equal to ③, less than 7. During the bending test, the change in the angle between the two wings of the sample is called ③. ①, tensile surface ②, angular deformation ③, bending angle 8, steel grades 16MnR, 16Mng, 15MnVR, which are used for boiler and pressure vessels in my country ③. ①, low carbon steel ②, high alloy steel ③, low alloy steel 9. The surface of the welding wire is generally copper-plated to prevent corrosion and facilitate the lubrication and ① of the welding wire. ①, Electrical conductivity ②, heat transfer ③, magnetic permeability 10, the corresponding brand of model E347-16 welding rod is ①. ①, A132 ②, A137 ③, A102 11. The arc voltage of melting electrode pulse gas shielded welding is very sensitive to the molten pool retention ability. Generally, ① V is the best. ①, 20~21 ②, 23~24 ③, 25~26 12. When calculating the load duration rate of the electrode arc welding power supply, the specified working cycle is ②. ①, 3min ②, 5min ③, 10min 13. Melting electrode argon arc welding uses ① mixed gas to weld carbon steel, stainless steel and higher-grade high-strength steel. ①, Ar+O2 ②, Ar+CO2 ③, Ar+He 14. The welding power cable is too long or coiled, which will cause welding current ①. ①, decrease ②, remain unchanged ③, increase 15. Carbon dioxide (CO2) gas shielded welding adopts ① transition, which can realize all-position welding of thin plates. ①, short circuit ②, drop ③, droplet 16. The nozzle diameter during melting electrode argon arc welding is generally about ②. ①, 10mm ②, 20mm ③, 30mm 17. The weld formed by the simple combination of butt weld and fillet weld is called ②. ①, load-bearing weld ②, combination weld ③, full penetration weld 18. When selecting the groove form, attention should also be paid to the welding material ①, weldability, groove processing ability and welding deformation. ①, Consumption ②, Features ③, Type 19. As shown in Figure (a), there is a T-shaped weld seam. The marking method on the drawing should be ③. (a) (b) (c) (d) ①, (b) ②, (c) ③, (d) 20. During the welding process, the base metal on both sides of the weld is rapidly heated and cooled under the action of the heat source, so this part of the metal will undergo ①. ①, Structural changes ②, thermal conductivity changes ③, electrical conductivity changes 21. In addition to transferring alloy elements (alloying) through the electrode coating to the weld seam (alloying), alloy elements can also be directly added to the molten metal through ②. ①, shielding gas ②, alloy welding wire ③ solvent 22, and the molten pool retention capacity curve of molten electrode pulse gas shielded welding increases with the increase of ②. ①, welding current ②, pulse frequency ③, pulse width ratio 23, for some boiler and pressure vessel products, the maximum depth of undercut defects allowed shall not exceed ① mm. ①, 0.5 ②, 1 ③, 1.5 24. When using manual carbon arc gouging, the general extension length of the carbon rod is ②. ①, 40~60 ②, 80~100 ③, 180~200 25. According to the GB150-1998 "Steel Pressure Vessel" standard, the welded joints of the main pressure-bearing parts of the vessel are classified into category ③. ①, 2②, 3③, 4 26. Ultrasonic waves are high-frequency (frequency greater than 20000Hz) ② waves beyond the human hearing range. ①, photon ②, mechanical wave ③, electromagnetic wave 27. Metallographic inspection is a test method to examine the internal metallographic structure of materials or welds and whether there are defects. It is divided into ② metallography and micro-metallography. ①, Side view ②, Macro ③, Oblique view 28. Welding of the longer T-beam in the picture below should mainly prevent ③. ①, angular deformation ②, twisting deformation ③, bending deformation 29. The deformation most easily caused by the workpiece welding shown in the figure below is ①. ①, angular deformation ②, twisting deformation ③, bending deformation 30. The "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" stipulates that the welder examination committee should prepare the welder examination ② based on the qualified welding process. ①, Welding process assessment ②, Welding process regulations ③, Welding current 31, "Boiler, pressure vessel and pressure piping welder examination and management rules" The validity period of passing the welder basic knowledge examination is ② months. ①, 3 ②, 6 ③, 9 32. "Boiler, Pressure Vessel and Pressure Pipe Welder Examination and Management Rules" The deformation angle of the plate specimen after welding is ②. ①, θ≤2° ②, θ≤3° ③, θ≤4° 33. There are mainly ③ types of droplet transfer forms in CO2 gas shielded welding. ①, 1 ②, 2 ③, 3 34. CO2 gas shielded welding usually uses the DC power supply ② connection method. ①, positive polarity ②, reverse polarity ③, Y 35, and the arc voltage of CO2 gas shielded welding should increase with the increase of the welding current used ③. ①, decrease ②, remain unchanged ③, increase 36. The size of the arc voltage of CO2 gas shielded welding determines ① and the droplet transfer form. It has a great influence on weld formation, spatter, welding defects and weld mechanical properties. ①, arc length ②, welding speed ③, welding current 37, CO2 gas shielded welding. When the welding wire extends too long, spatter will ①. ①, increase ②, remain unchanged ③, decrease 38. During CO2 gas shielded welding, the electric field strength of the arc ① The electric field strength of argon arc welding. ①, greater than ②, equal to ③, less than 39, the name of the supplementary symbol in GB324 "Weld Symbol Representation" is ③. ①, mark symbol ②, equal symbol ③, on-site symbol 40, the name of the supplementary symbol of GB324 "Weld Symbol Representation" is ③. ①, square symbol ②, circular symbol ③, surrounding weld symbol 42, the name of the basic symbol of GB324 "Weld Symbol Representation" is ③. ①, spot weld ②, semi-circular weld ③, back cover weld 42, the picture below shows CO2 gas shielded welding ①. 10°~15° ①, left welding method welding direction ②, right welding method ③, neither method 43. When the welding current of CO2 gas shielded welding is equal, the arc root area when the welding wire is the anode, ① the arc root area when the welding wire is the cathode. ①, greater than ②, equal to ③, less than 44, the welding voltage of CO2 gas shielded welding is higher. As the welding current increases, the droplet transfer frequency increases and the volume of the droplet particles will increase ③. ①, increase ②, remain unchanged ③, decrease 45. When welding with CO2 gas shielded welding, in order to obtain the highest short circuit frequency, there must be an optimal arc voltage value. When the welding wire diameter is 1mm, the value is approximately ② V. ①, 15 ②, 20 ③, 25 46. Every time there is a short circuit in CO2 gas shielded welding, the voltage is zero and the current will increase, and its maximum value can be ① times the welding current. ①, 2~4 ②, 3~5 ③, 4~6 47. When using CO2 gas semi-automatic shielded welding, when ③ wire feeding system is selected, the range of activity of the welding gun is the smallest. ①, push-pull type ②, wire-drawing type ③, push-wire type 48, CO2 gas shielded welding, it will occur when a small amount of argon is added. As argon increases this year and next, ② will decrease. ①, current ②, spatter rate ③, sub-jet 49, CO2 gas shielded welding ② During the transition, the penetration of the welding arc is large and it is easy to burn through the weldment, so the assembly quality requirements for the weldment are stricter. ①, droplet ②, fine particles ③, short circuit 50, CO2 gas shielded welding ③ During the transition, the penetration depth is shallow, so the weldment is required to leave a smaller blunt edge, or even no blunt edge. ①, droplet ②, fine particles ③, short circuit 51, CO2 gas shielded welding and other metal arc welding, often use DC ②, the impact force of the charged holding point is small, and it is easier to produce small particle transitions. ①, forward connection ②, reverse connection ③, connection 52. During CO2 gas shielded welding, CO2 gas is the protective gas during the welding process. Although it has a strong oxidizing effect at high temperatures, CO2 gas eliminates the harmful effects of ①. ①, Nitrogen ②, Helium ③, Ammonia 53. The butt weld of 1Cr18Ni9Ti plate in the picture below has been inspected by penetrant flaw detection, and the ① defect was found. ①, Crystal shrinkage cavities ②, cracks ③, undercut 54. CO2 gas shielded welding usually requires the water content in the shielding gas to be ≤1~2g/m3. At the same time, a gas ② should be installed at the outlet of the gas cylinder to remove water and prevent the moisture in the gas from freezing at the outlet of the gas cylinder. ①, cooler ②, dryer or preheater ③, dehumidification 55, contact tip manufacturing materials in CO2 gas shielded welding gun generally use ②. ①, pure lead ②, pure copper ③, pure silver 56, flux cored wire CO2 gas shielded welding belongs to ③ protection. ①, gas ②, slag ③, gas-slag combination 57. When arc closing in CO2 gas shielded welding, in order to protect the solidification of molten metal in the arc crater, the gas supply system should ③ cut off the gas during arc closing. ①, advance 1~2s ②, simultaneously ③, lag 2~3s 58. When CO2 gas shielded welding is welding steel number 16MnR plate, the CO2 gas shielded welding wire steel number selected is ②. ①, H10Mn2 ②, H08Mn2SiA ③, H0Cr21Ni10Ti 59. Solid wire gas shielded welding adopts ② method. ①, slag protection ②, gas protection ③, gas-slag combined protection 60. When melting electrode argon arc welding, ① transition is generally used. ①, Jet ②, Short circuit ③, Coarse droplets (4) Submerged arc welding test question set: 1. Keep your body dry and wear standard labor protection gear. ② Human body resistance is one of the main methods to prevent electric shock. ①, reduce ②, increase ③, maintain 2. When welding and cutting at height, when encountering wind force above ③, the operation should be stopped. ①, Level 4 ②, Level 6 ③, Level 8 3. When entering the container for gas welding, ignition and flameout should be carried out at ②. ①, outside the container ②, inside the container ③, in a wind-free place 4. The purpose of inspection during the welding process is to promptly discover existing quality problems so that they can be corrected at any time to prevent the occurrence of ②, and at the same time, the defects that occur can be dealt with in a timely manner. ①, Accident ②, Defect ③, Repair 5. According to the working pressure (P) classification of pressure vessels, they can be divided into four types of working pressure vessels, among which the working pressure (P) of medium-pressure vessels is ③. ①, 0.1Mpa≤P<1.6Mpa ②, =1.6Mpa ③, 1.6Mpa≤P<10Mpa 6. During the boiler manufacturing process, when the welding ambient temperature is lower than 0℃, there is no preheating measure. ③ Carry out welding. ①, yes ②, it is best not to weld, but if the task is tight, it is ok ③, not allowed 7. After the sample is bent, its front side becomes a curved tensile surface, which is called ①. ①, face bend ②, back bend ③, side bend 8. The letter B in steel number Q235B represents ②. ①, Deoxidation method ②, Quality grade ③, Heat treatment status 9, Metal tensile strength is represented by σb, and its measurement unit is ①. ①, Mpa ②, J ③, J/cm2 10. The purpose of the cold bend test of welded joints is to check the ② of the joints. ①, strength ②, plasticity ③, toughness 11, and weld ③ have the greatest impact on the fatigue strength of butt joints. ①, transition radius ②, groove ③, reinforcement 12, and T-shaped joint, as the K value of the welding leg increases, the stress concentration coefficient ②. ①, increase ②, decrease ③, remain unchanged 13. When welding low-alloy structural steel, excessive welding heat input will significantly reduce the joint ①. ①, impact toughness ②, tensile strength ③, fatigue strength 14. The commonly used sealing test method is ③. ①, submerged water inspection ②, ammonia inspection ③, kerosene leakage 15. The slag-forming agent in the electrode coating melts to form slag covering the surface of the weld, which can not only isolate the air to prevent oxygen and nitrogen damage, but also improve the weld ③. ①, size ②, stability ③, forming 16. In the weld groove size symbol, the symbol of the root gap is ③. ①, x ②, p ③, b 17. In the weld groove size symbol, the symbol of the blunt edge is ②. ①, x ②, p ③, b 18. A series of events between slag and molten metal during welding