Chongqing Nan'an District Pipes City Gas Water Design Institute Water Conservancy Huan Bao / Energy Saving Gas Municipal Shi Zheng Gong Yong Engineering Sewage Treatment Drainage Pipes Materials Pipes Sleeves名牌产品守合同重信用企业市名牌产品市级知识产权优势企业省级高新技术企业市级高新技术企业高新技术企业著名商标市著名商标ISO9001认证ISO14001认证ISO18001认证