DRIVES OF MECHANISMS OF AUTOMATIC MACHINES FOR ORBITAL TIG WELDING OF METAL PIPELINE BUTT JOINTS IN NPP POWER UNITS

摘要

Electric drives are integral devices in any welding installation for are and plasma welding. Since a number of specific requirements are made to the accuracy and reliability of the actuating mechanisms in modern automatic machines for orbital welding of position butt joints of pipelines in NPP units, these requirements are also imposed on their driving mechanisms, that required development of the latter. The schemes of unified reversible DC drives of actuating mechanisms in modern automatic machines for orbital welding of position butt joints in NPP pipelines are described. A transistor drive with feedback from an optical speed sensor, characterized by high reliability, ability to accurately preset (program) the rotation speed of the motor shaft, absence of mechanical switching contacts for starting or stopping, or for reversing, as well as a device for high-precision high-speed automatic are voltage control was designed. The results of industrial operation of some automatic machines for orbital welding designed at the Scientific and Engineering Center of Welding and Control in the Field of Nuclear Energy (SEC WCNE), are given, which use the described reversing drives and the device for automatic are voltage control. The aim of this, paper is to present the results of the work carried out at the SEC WCNE in the direction of designing components of automatic machines for orbital welding of position butts in thin-walled pipelines from austenitic, pearlitic and carbon steels and nonferrous metal alloys (except for aluminium and its alloys).