进入面 meaning in English

advancing side
entrypiston

It is not allowed to be installed with the access panel facing up or down
安装时不允许将进入面板朝上或朝下。
Cut a space with the following dimensions into the panel for installation
以以下尺寸削减出进入面板的空间安装。
Standard practice for ultrasonic examination of steel with convex cylindrically curved entry surfaces
带有凸圆柱弯曲进入面钢的超声检验