Flangeless and Threadless valves and Fittings Applied in Water Supply Pipelines
无法兰和无螺纹的连接装置在饮用水管道中的应用
Some Infection Factors on Threadless Adhesive Binding Quality & Pondering on Upswing of Coal Geological Industrial Printed Matter Quality
谈影响无线胶订质量的几个因素&关于提高煤炭(田)地质行业印品质量的思考