焊工培训题目（Welder training topics）.docVIP

焊工培训题目（Welder training topics） Exercise 1 A. Completion 1 welding is the combination of (heating) or (pressurizing), or both, and with or without (filling material) to make the workpiece come together 2, in accordance with the welding process of metal in the state and process characteristics, the welding methods can be divided into (melting welding), (pressure welding) and (brazing) 3 the most dangerous defect is (weld crack) 4 is the use of gas (gas) and combustion gas mixed combustion flame to melt the workpiece at the joint of the metal wire and the metal is firmly connected to method 5 is the essence of the metal cutting process of iron in pure oxygen in the combustion process According to the 6 different mixed oxygen and combustible gas ratio, gas welding flame can be divided into neutral flame, carbonizing flame and oxidizing flame The 7 electrode arc welding arc method and scratch method was two 8 flux cored wire gas shielded welding is essentially a method of welding with gas slag protection 9 plasma arc welding through mechanical compression, heat compression and magnetic compression of three kinds of compression, so that the plasma arc energy concentration, high temperature, good arc stiffness 10 chemical and fuel container and pipe welding, the displacement welding with pressure and displacement welding two methods 11 the three conditions that must occur simultaneously are combustible material, combustion supporting substance and ignition source Two choice questions 1 the best weldability of carbon steel is A, A, low carbon steel, B medium carbon steel, C high carbon steel 2 to increase A, the weld thickness and remaining height are increased, while the weld width is almost constant, A welding current B, arc voltage C, welding speed 3 is the C cutting process of C preheating combustion slag The main risk is the B 4 welding and cutting of fire and explosion 5 the flame that is widely used in underwater flame cutting is B oxyhydrogen flame 6D can not burn,