1.高強(qiáng)螺栓的緊固:必須分兩次進(jìn)行,次為初擰。初擰緊固到螺栓標(biāo)準(zhǔn)軸力(即設(shè)計(jì)預(yù)拉力)的60%~80%,初擰的扭矩值不得小于終擰扭矩值的30%。第二次緊固為終擰,終擰時(shí)扭剪型高強(qiáng)螺栓應(yīng)將梅花卡頭擰掉。為使螺栓群中所有螺栓均勻受力,初擰、終擰都應(yīng)按一定順序進(jìn)行。
1. Fastening of high strength bolt: it must be carried out twice, and the first time is the initial tightening. The initial tightening should be 60% - 80% of the standard axial force (i.e. the designed pre tension), and the torque value of the initial tightening should not be less than 30% of the final tightening torque value. The second tightening is the final tightening. When the final tightening, the plum blossom chuck should be screwed off. In order to make all bolts in the bolt group bear uniform force, the initial tightening and final tightening should be carried out in a certain order.
2.一般接頭:應(yīng)從螺栓群中間順序向外側(cè)進(jìn)行緊固。
2. General joints: the bolts shall be tightened from the middle to the outside.
3.從接頭剛度大的地方向不受約束的自由端進(jìn)行。
3. From the joint with high stiffness to the free end.
4.從螺栓群向四周擴(kuò)散的方式進(jìn)行。
4. Spread from the bolt group center to the surrounding.
初擰扳手應(yīng)是可以控制扭矩的,初擰完畢的螺栓,應(yīng)做好標(biāo)記以供確認(rèn)。為防止漏擰,當(dāng)天安裝的高強(qiáng)螺栓,當(dāng)天應(yīng)終擰完畢。終擰應(yīng)采用專用的電動(dòng)扳手,如個(gè)別作業(yè)有困難的地方,也可以采用手動(dòng)扭矩扳手進(jìn)行,終擰扭矩須按設(shè)計(jì)要求進(jìn)行。用電動(dòng)扳手時(shí),螺栓尾部卡頭擰斷后即表明終擰完畢,檢查外露絲扣不得少于2 扣,斷下來的卡頭應(yīng)放入工具袋內(nèi)收集在一起,防止從高空墜落造成事故。
The initial tightening wrench should be able to control the torque, and the bolts after the initial tightening should be marked for confirmation. In order to prevent missing tightening, the high-strength bolts installed on the same day should be finally screwed on the same day. Special electric wrench shall be used for final tightening. Manual torque wrench can also be used in case of difficulties in individual operation, and final tightening torque shall be carried out according to design requirements. When using the electric wrench, the final tightening is finished after the bolt tail clamp is broken. Check that the exposed screw threads shall not be less than 2. The broken clamps shall be put into the tool bag and collected together to prevent safety accidents caused by falling from high altitude.