Method for electrified spanning construction of high-voltage power transmission and transformation line

The invention discloses a method for electrified spanning construction of a high-voltage power transmission and transformation line. The method comprises the following steps of: (1) preparation for construction: computing the position, the height and the width of a spanning frame; (2) building of the spanning frame: according to the designed spanning frame model, installing an auxiliary lifting pole for suspending pulleys on towers at two sides of a span of a newly-built line, suspending double-layer pulleys on the lifting pole, penetrating the double-layer pulleys by Deenyma ropes to form ropeways which are regarded as carrying ropes of a safety net and suspending the safety net under the carrying ropes through suspending belts and small pulleys; (3) extension of insulation guide ropes; (4) extension of conducting wires and ground wires: extending the conducting wires, the ground wires and installation accessories above the safety net by utilizing the insulation guide ropes; and (5) dismantling of the built