(GB30-76、GB5780/5781-86?。8.8级)六角螺母(GB52、GB6170-86?。(GB/T3632-95?。(GB/T1228/1229/1230-91?。class="lpneu">.9级)内六角圆柱头螺钉(GB70-85?。class="lpneu">.8级?。class="lpneu">.9级)圆头内六角螺钉(GB/T70.2-2000?。class="lpneu">.9级)六角法兰面螺母(GB6177-86?。