Electric wrench is mainly used for fastening high-strength bolts. Its purpose is to destroy the plum head of the high-strength torsional shear bolt. In order to understand the electric torque shear wrench, we must first understand the torque shear type high strength bolt.

　　高強(qiáng)螺栓按施工工藝分為:扭剪型高強(qiáng)螺栓和大六角高強(qiáng)螺栓。高強(qiáng)度扭剪螺栓一端為花鍵端，螺栓螺母一般為圓形(不需要用扳手固定)。

　　According to the construction technology, high-strength bolts are divided into: torsional shear type high-strength bolts and large hexagon high-strength bolts. One end of the high-strength torsional shear bolt is spline end, and the bolt and nut are generally round (no spanner is needed to fix them).

　　扭剪式高強(qiáng)度螺栓(TCB)的加捻過程:(理解“緊固軸力”)

　　Twisting process of torsional shear high strength bolt (TCB): (understand "tightening axial force")

　　削弱斷面的剪切過程

　　Shear process of weakened section

　　同時(shí)將扭矩施加于被組裝材料的內(nèi)部拉應(yīng)力，使其達(dá)到設(shè)計(jì)值(“拉緊軸力”)，材料相應(yīng)的抗剪強(qiáng)度剛好使桿頭截面弱化和扭轉(zhuǎn)。

　　At the same time, the torque is applied to the internal tensile stress of the assembled material to make it reach the design value ("tension shaft force"), and the corresponding shear strength of the material just makes the cross section of the rod head weaken and twist.

　　分析表明，即使是扭轉(zhuǎn)剪切螺栓也不是直接反饋螺桿內(nèi)的預(yù)緊力值，而是由抗剪強(qiáng)度代替。測(cè)試項(xiàng)仍然不是直接項(xiàng)，并且存在替換錯(cuò)誤。

　　The analysis shows that even the torsional shear bolt does not directly feedback the preload value in the screw, but is replaced by the shear strength. The test item is still not a direct item and there are replacement errors.

　　因此，為了保證扭剪螺栓的施工質(zhì)量，有必要對(duì)螺栓切割時(shí)的“緊固軸力”進(jìn)行測(cè)量。該值應(yīng)符合預(yù)緊力的設(shè)計(jì)值。

　　Therefore, in order to ensure the construction quality of the torsional shear bolt, it is necessary to measure the "fastening axial force" when the bolt is cut. This value shall be in accordance with the design value of preload.

　　根據(jù)gb jgj-82 6.1.1的規(guī)定，在高強(qiáng)度螺栓連接副中，扭轉(zhuǎn)-剪切高強(qiáng)度螺栓應(yīng)具有一個(gè)墊片和一個(gè)母片。在接受扭剪式TCB時(shí)，注意桿頭擰合合格。

　　According to 6.1.1 of GB jgj-826.1, the torsional shear high strength bolt should have a gasket and a mother plate. When accepting the torsional shear TCB, pay attention to the qualified screw in of the rod head.

　　扭剪作為大型六角升級(jí)版，其有點(diǎn)貴，施工、檢驗(yàn)相對(duì)簡(jiǎn)單，優(yōu)點(diǎn)明顯。但國(guó)產(chǎn)產(chǎn)品受國(guó)標(biāo)產(chǎn)品標(biāo)準(zhǔn)型號(hào)限制(僅10.9級(jí)，尺寸24M)。理解其核心原理的關(guān)鍵是掌握“扭矩系數(shù)”和“緊固軸力”兩個(gè)概念。

　　As a large-scale hexagon upgraded version, torsion shear is a little expensive, relatively simple in construction and inspection, with obvious advantages. However, the domestic products are limited by the national standard product model (only 10.9 grade, the maximum size is 24m). The key to understand its core principle is to master the concepts of "torque coefficient" and "tightening shaft force".

　　扭剪式螺栓采用電扭剪式扳手結(jié)構(gòu)，其根部采用前后扭桿直接通過“桿頭”夾緊螺釘本身，因此在扭轉(zhuǎn)時(shí)不會(huì)出現(xiàn)共轉(zhuǎn)現(xiàn)象。本產(chǎn)品的設(shè)計(jì)思路是:當(dāng)螺桿達(dá)到預(yù)緊值時(shí)，材料能承受相應(yīng)的剪切力，設(shè)計(jì)并弱化梅花頭根部截面，達(dá)到切割的目的。

　　The torsion shear bolt adopts the structure of electric torsion shear wrench, and its root adopts the front and rear torsion bars to directly pass through the "rod head" to clamp the screw itself, so there is no co rotation phenomenon during torsion. The design idea of the product is: when the screw reaches the pre tightening value, the material can bear the corresponding shear force, design and weaken the cross section of the root of the plum head, so as to achieve the purpose of cutting.