Běi / fāng / dōng / tiān / de / shū / yóu / guǎn / dào / bì / xū / ān / zhuāng / bàn / rè / xì / tǒng / ， / fáng / zhǐ / yuán / yóu / níng / gù / 。

北方冬天的输油管道必须安装伴热系统，防止原油凝固。

Oil pipelines in northern China must be equipped with heat tracing systems in winter to prevent crude oil from solidifying.