created sense approved 锪孔/鍃孔 · huōkǒng · countersink or counterbore
锪孔 / 鍃孔
huōkǒng
countersink or counterbore
An enlargement at the outer end of a drilled hole, either funnel-shaped (a countersink) or cylindrical (a counterbore).
在安装沉头螺丝前，通常需要先对孔进行锪孔处理。