实用经验二则北方勘察研究院张改珍大直径长筒体的钻孔工艺在加工直径为Φ３７７ｍｍ，壁厚为２５ｍｍ，长约８ｍ，重１．７ｔ的简体中，简体表面要加工出不均匀分布的１００多个大小不等的孔，孔径从Φ２０ｍｍ至中１０９ｍｍ，而且Φ５０ｍｍ以上的孔还要划不同尺寸的窝... Practical experience of the two Northern Investigation Institute Zhang Gengzhen large diameter long cylinder drilling process in the processing of diameter Φ377mm, wall thickness of 25mm, length of about 8m, weight 1.7t simplified Simplified surface to be processed into an uneven distribution More than 100 holes of different sizes, the aperture from Φ20mm to 109mm, and Φ50mm above the hole also draw different size of the nest ...