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Causes of bolt break

Dec. 06, 2019

Causes of bolt break

1. Due to the material of the bolt, if the material we choose is better, then the quality of our bolt will be better. If we choose a poorer material, then our bolts will break more to a certain extent.

2. The strength of the bolt is not high enough. If the pressure of the bolt is greater than the strength of the bolt, the bolt will easily break. Therefore, when we use a round head stud bolt, it is best to know how much strength the bolt can withstand, so that we can choose a bolt with a strength higher than this, and the possibility of the bolt breaking will be reduced.

3, due to manufacturing failure, many bolts will be due to production failure, so there is no way to give full play to the quality of standard bolts, to a certain extent, will cause bolts to break. We must go through inspection after the production of bolts, so that we can ensure that the bolts are qualified before they are sold. This is also the most basic guarantee for consumers.

4, due to the fatigue strength of the bolt. The most common factor for bolts to break is due to their fatigue strength. We used the bolt at the beginning without any problems, but after the operation of the object, there may be a certain degree of looseness. When the loosening is continued, the fatigue strength of the bolt will increase, and when the bolt is reached, The end of the range, the bolt will break.

Hexagon Head Bolt

Hexagon Head Bolt

Preventive measures against bolt breakage

1.Sega Horn

2.Improve bolt processing technology

3.Improve the standard section processing technology

The quality of the bolt is determined by conditions such as the length, specifications, type, and connection type of the bolt.

The pre-tightening torque of the bolt causes the bolt to be subjected to two kinds of forces, tensile and shear stress, and the pre-tightening force is controlled to ensure that the flange connection system is tight, leak-proof, and runs safely and reliably for a long period of time. The split washerssurface must have a sufficient sealing ratio. Pressure, especially under high temperature conditions, the gasket will produce aging, creep relaxation, thermal deformation of flanges and bolts, so the sealing of the high temperature connection system is much more difficult than normal temperature, at this time the application and control of the bolt pretension force appears It is very important that too much or too little preload will adversely affect the seal. Excessive pre-tightening force of the bolt will cause the gasket to be crushed and lose its elasticity, and even the bolt will be broken. Too small pre-tightening force of the bolt will cause the residual compression stress on the gasket surface after compression to not reach the working seal. Specific pressure, resulting in leaks in the connection system. Therefore, how to control the bolt pretension is a problem that must be paid attention to in production.

The tensile strength and yield strength of the hexagon head bolt determine the strength of the bolt. The greater the strength, the longer the life.

Fatigue strength of bolts. It is related to the dangerous section area, the maximum and minimum stress on the bolt, the bolt stress amplitude, and the average bolt stress.

The overload failure of a bolt refers to a sudden and instantaneous breakage during service. This failure has no obvious symptoms in advance, so its damage is serious.