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1、概述第一批动力支架是由几根柱子支撑一个顶梁构成本单元的简单梁柱系统发展过来的.由于把两根或更多一些的柱子和梁作为一个整体前移的装备,就产生了一种较安全和很少体力劳动消耗的支护系统.在英国,节式和垛式支架都经过多年发展,但后来重点转向垛式,且所有流行的常用支架设计都属这一类.与之同时,欧州国家和苏联也经历了类似的发展.大约在二十年前,苏联开始使用
1. Overview The first power-stand was developed by a simple beam-column system that consists of several columns supporting a roof beam and forming the unit. As two or more columns and beams are advanced as a unit, Resulting in a safer and less labor-intensive support system.In the UK, the pallets and pallets have been developed over the years, but later switched to the palletizing, and all popular designs for the stent are of this type At the same time, European states and the Soviet Union experienced similar developments, and about two decades ago, the Soviet Union started to use