elliptical shaft

• 椭圆形井筒

elliptical shaft的用法和样例：

例句

1. The mine flooding happed during construction of the air shaft in Qidong Coal Mine.
   祁东煤矿风井在建井过程中，发生钻井井壁突水事故，井筒被淹。
2. Cement injection of perforating holes in a frozen pipe is a wholly -new technology for consolidating shaft wall rock and stopping water of frozen shafts in coal mines.
   冻结管射孔注浆是在对石油输油井射孔技术和地面注浆技术进行研究的基础上，开发出的一种用于煤矿冻结井筒围岩加固和堵水的全新技术。