前言南岔机务段自1973年3月试制和使用合成塑料闸瓦(以下简称合成瓦)代替磷灰铸铁闸瓦(以下简称铁瓦),同时供应佳、鹤、林、西鸡西、缓芬河、北安、哈尔滨等机务段调车机车使用,经过5年多的试用,取得一些成效。由于合成瓦体轻、耐磨、减少铁粉飞扬、有利保养机车,更换方便、使用期长,节约钢材,降低成本、深受乘务员的欢迎。特别是调车、补 Preface Nancha locomotive section of trial production and use of synthetic plastic brake shoe (hereinafter referred to as synthetic tile) in March 1973 instead of phosphorus gray cast iron brake shoe (hereinafter referred to as iron tile), at the same time supply good, crane, forest, West Jixi, , Bei’an, Harbin and other locomotive shunting locomotive use, after more than five years of trial, and achieved some results. As the synthesis of tile body light, wear-resistant, reducing the iron flying, favorable maintenance locomotive, easy replacement, long service life, saving steel, reduce costs, welcomed by the flight attendants. In particular, shunting, fill