探究高強(qiáng)螺栓易松動(dòng)的原因，一種是客觀原因，由于機(jī)械運(yùn)動(dòng)，該螺栓防松不好等而引起松動(dòng)；還有一種是人為因素，因疏忽而沒(méi)有擰緊等。（我們從客觀和人為原因量方便做分析）
Explore the reasons why high-strength bolts are easy to loosen. One is the objective reason, which is caused by mechanical movement and poor anti loosening of the bolts; There are also human factors, such as failure to tighten due to negligence. (we analyze it from objective and human factors)
具體客觀原因
Specific objective reasons
1 、螺栓質(zhì)量差。 螺栓防松不好往往與螺栓的制造精度不高、防松設(shè)計(jì)缺陷有關(guān)。 如華夏塔吊的高強(qiáng)螺栓的防松螺母明顯偏窄，其防松效果自然就差一些。
1. Poor bolt quality. The poor anti loosening of bolts is often related to the low manufacturing accuracy of bolts and the defects of anti loosening design. For example, the locknut of the high-strength bolt of Huaxia tower crane is obviously narrow, and its anti loosening effect is naturally poor.
2 、螺紋牙滑扣。 如螺栓多次裝拆，可能發(fā)生螺紋牙滑扣現(xiàn)象，導(dǎo)致螺栓松動(dòng)。
2. Thread thread sliding buckle. If the bolts are installed and disassembled for many times, the thread thread may slip, resulting in loosening of the bolts.
3 、螺紋斜面間的摩擦力瞬時(shí)消失或減小。 塔機(jī)在工作中，經(jīng)常受到振動(dòng)、沖擊和變載荷作用，或者溫度變化很大環(huán)境節(jié)，這樣，螺栓連接中的螺紋斜面間的摩擦力就可能瞬時(shí)消失或減小。這種現(xiàn)象的多次重復(fù)出現(xiàn)就會(huì)使連接逐漸松脫，影響連接的剛性及緊密性。
3. The friction between the inclined surfaces of the thread disappears or decreases instantaneously. The tower crane is often subjected to vibration, impact and variable load during operation, or the temperature changes greatly. In this way, the friction between the thread slopes in the bolt connection may disappear or decrease instantaneously. Repeated occurrence of this phenomenon will gradually loosen the connection and affect the rigidity and tightness of the connection.
具體人為原因
Specific human causes
1、人為疏忽。由于個(gè)別安裝人員的疏忽而導(dǎo)致部分螺栓未緊固，而檢查人員因疏忽而未發(fā)現(xiàn)。這里需要著重強(qiáng)調(diào)對(duì)安裝人員、頂升作業(yè)人員、操作人員的技術(shù)交底，強(qiáng)調(diào)安裝、頂升工序完成后的自檢、互檢，防止遺漏高強(qiáng)度螺栓的擰緊，防止這種嚴(yán)重隱患的發(fā)生和存在。
1. Human negligence. Some bolts were not fastened due to the negligence of individual installers, but the inspectors did not find them due to negligence. Here, it is necessary to emphasize the safety technical disclosure to the installation personnel, jacking operators and operators, and the self inspection and mutual inspection after the completion of the installation and jacking procedures to prevent the omission of tightening of high-strength bolts and the occurrence and existence of such serious safety hazards.
2、工具原因。由于無(wú)專用扳手或力矩扳手，作業(yè)人員只能憑各自的經(jīng)驗(yàn)或感覺(jué)對(duì)螺栓緊固，每個(gè)人的力量各不相同，導(dǎo)致各個(gè)螺栓的預(yù)緊力矩不同，當(dāng)同一連接處的一組連接副預(yù)緊力相差過(guò)大時(shí)，各連接副的螺栓所承受的軸向力就相差很大，預(yù)緊力大的螺栓長(zhǎng)期處于重載荷下，容易產(chǎn)生螺栓松動(dòng)及疲勞斷裂等情況。
2. Tool reason. Since there is no special wrench or torque wrench, the operators can only fasten the bolts according to their own experience or feeling. The strength of each person is different, resulting in different pretightening torques of each bolt. When the pretightening force of a group of connection pairs at the same connection is too large, the axial force borne by the bolts of each connection pair is very different. The bolts with large pretightening force are under heavy load for a long time, which is prone to bolt loosening and fatigue fracture.
The above is the detailed introduction of the torsion shear wrench manufacturer. I hope it will help you. If you have any questions, please contact us. We will provide you with services with a professional attitude http://www.hkystar.com
