段管线 meaning in English

depot siding
section line

The calculation is based on the actual length of the first line even if this line has a full or partial double track or more tracks , excluding double tracks , stationsidings , tracks under the charge of stations , , branch lines , specialpurpose lines and the non payable connecting lines
凡是全线或部分建成双线及以上的线路，以第一线的实际长度计算；复线、站线、段管线、岔线和特殊用途线以及不计算运费的联络线都不计算营业里程。