国产一级AV免费高清_怡红院成永久免费人视频_精品国精品国产应用久_日本最新免费二区三区在线观看

　　Changde five counties and one city natural gas transmission and distribution pipeline project, by Hunan Hunan and Jiangxi Three Gorges gas investment limited liability company construction, the project is a total length of 245.9 km pipeline, design pressure 4.0 MPa, the design of the largest annual gas transmission capacity of 442 million cubic meters , The construction of a total of three cathodic protection station, the station cathodic protection by our company construction. Line cathodic protection materials, site cathodic protection materials provided by our company.