本文介绍了一种新型的用于气门座圈密封带加工的镗车头，就其结构及工作过程做了较详细的阐述。

This paper introduces a new device of boring the valve-seat and gives the relatively detailed explanation of the device's structure and working-process.

youdao

本文介绍了一种新型的用于气门座圈密封带加工的镗车头，就其结构及工作过程做了较详细的阐述。

This paper introduces a new device of boring the valve-seat and gives the relatively detailed explanation of the device's structure and working-process.

youdao