Welder skill assessment test question bank

Author: Chief Editor: Huang Taoxun
Publisher:
Publish Date: 2005-01-01
Features: This question bank is designed to be used in conjunction with the vocational training textbooks "Primary Fitter Technology," "Intermediate Fitter Technology," and "Advanced Fitter Technology." The book is divided into two main parts: questions and answers. The question section is further divided into knowledge requirement questions and skill requirement questions, and includes mock exams.
Fragment:?br>Twisting phenomenon. ()???100. The allowance before scraping is determined based on the size of the workpiece's scraping area. A larger area requires a larger allowance, while a smaller area can have a smaller allowance. 101. The original flat plate is scraped using the method of direct grinding. If, after scraping, any two pieces can be ground together without any concave or convex phenomena, the scraping of the original flat plate meets the requirements. (??) 102. Scraping processing can achieve a finer surface roughness, mainly by utilizing the pushing and polishing of the negative rake angle of the scraping tool. (??) 103. The material of the grinding tool should be slightly harder than the workpiece material, otherwise its geometric accuracy is difficult to maintain, affecting the grinding accuracy. (??) 104. During grinding, to reduce the surface roughness value of the workpiece, the grinding pressure can be increased. 105. Carbide abrasive materials are harder than corundum-based abrasive materials. (??) 106. The trajectory of linear grinding motion not only achieves high geometric accuracy but also results in a finer surface roughness. (??) 107. Grinding is a precision machining process that can achieve precise dimensions, precise geometric accuracy, and extremely fine surface roughness. (??) 108. Grinding is a machining method that removes the surface layer metal of parts mainly through chemical action. (??) 109. When grinding an external cylindrical surface, the reciprocating motion trajectory of the grinding sleeve must be correct, and the formation of the crosshatch lines should be 45°. (??) 110. Grinding fluid plays a role in, cooling, and lubrication during grinding processing. 111. Assembly work includes preparation before assembly, sub-assembly and final assembly, adjustment, inspection, and commissioning. (??) 112. The complete interchange method is used in assemblies with fewer components and lower precision requirements. 113. The process of assembling parts and subassemblies into the final product is called sub-assembly. 114. When using the grouping selection method for assembly, increasing the number of groups can improve assembly precision. (??) 115. The matching assembly method requires higher machining accuracy for parts. (??) 116. Regular planned maintenance work includes major repairs, minor repairs, and first-level maintenance. (??) 117. Natural wear refers to damage gradually produced under normal operating conditions due to long-term effects of friction and chemical factors. (??) 118. Second-level maintenance refers to the daily maintenance and upkeep work performed by operators on mechanical equipment. (??) 119. Threaded joints are detachable fixed connections. (??) 120. Threaded joints can be divided into three types: normal fit, transition fit, and clearance fit, depending on the nature of the outer or inner diameter. (??) 121. To ensure torque transmission, when installing wedges, a slight interference fit between the key side and the key is required. (??) 122. In general, the centering method for spline fits is the outer diameter centering. 123. The flat key connection transmits torque by the upper surface of the flat key contacting the bottom surface of the hub. (??) 124. Pin connections serve to fasten or locate connections in machinery. (??) 125. Spring washers belong to mechanical methods of preventing loosening. (??) 126. The specification of taper pins is indicated by their small-end diameter and length. (??) 127. All pipe connections are detachable connections. (??) 128. For cylindrical interference connections, the minimum interference should generally be equal to or slightly greater than the maximum required interference. (??) 129. Interference connections achieve fastening by causing elastic deformation in the connecting parts. (??) 130. The cold assembly method is suitable for interference fits with smaller interference values. (??)