clearances间隙clearancen.清除；清理；清仓甩卖；间隙；许可证；结关；通关clearance gauge method隙规检查法clearance compensation缝隙损失clearance of particles颗粒清除clearance of expansion胀隙Clearance of labyrinth篦齿间隙clearance of buildings建筑物间距clearance loading gage载货限定外形尺寸clearance between roll辊间间隙clearance leakage flow间隙泄漏流clearance limit survey净空区测量