摘要
根据磁偶极子链近似理论对Betz环的分析结果,推导出下列关系:(m-1)/mlnm=2(h-a)/Dln(D/D-2h)(其中m=D/d,D-环外径,d-环内径,a-小孔半径,h-小孔埋藏深度),从而得悉:D、d、a、h中只有3个是独立的。由上式的数值计算证明:英国的BS 6072—1981标准试件设计合理,而日本的JISG 0565—1982中B型对比试件的内径过小,无法达到环的使用目的,给出了改进后的合理内径尺寸。
Abstract: On the basis of the analytical result of Betz's ring by the approximate theory of magnetic dipole chains, the function below was derived for the magnetization of a testing ring through the threading-bar technique: (m-1)/mlnm=2(h-a)/Dln(D/D-2h)(in which, m=D/d, D-outer diameter of the ring, d-inner diameter of the ring, a-radius of the little hole, h-buried depth of the little hole). Whereby it is known that only three among D, d, a and h are independent. The digital calculation from this formula proved that the design of the British standard testing ring BS 6072-1981 was reasonable, and that the core diameters of the Japanese comparing blocks Type B, JISG 0565-1982 were too small to reach their employed target. The rational sizes of the inner diameters after innovation were given in the present paper.
出处
《无损检测》
2009年第1期4-6,共3页
Nondestructive Testing
基金
国家自然科学基金资助项目(50371045后续)
关键词
磁粉探伤
环形试件
几何尺寸
穿棒法
Magnetic particle inspection
Testing ring
Geometrical dimensions
Threading-bar technique