Anti-loose method of non-standard parts

Today, the editor will introduce to you the commonly used methods of preventing loosening of non-standard parts in Qingdao:

How to prevent loosening of bolts, studs and nuts

1. The use of locking steel wire to prevent loosening is a commonly used method for preventing loosening, and it is the simplest and most economical;

2. Using spring washers to prevent loosening is also a common method for preventing loosening. However, according to relevant theories and foreign experience analysis, it is found that this method is very ineffective, and will tend to be loosened, and it will damage the precision machined surface very well. Therefore, the company has banned the use of spring pad anti-loose methods in the design;

3. The screw locking glue is anti-loosening and has good effect, especially suitable for occasions where disassembly and assembly are not frequent.

4. For bolts of grade 8.8 and above, if the ratio of the length to the nominal diameter is greater than 5, the anti-loosening element can be omitted under the condition of strictly controlling the pre-tightening force. In this way, even under the impact load, generally enough residual pre-tightening force can be guaranteed to prevent the bolts and nuts from loosening. According to this method, when designing the bolt, the effective clamping length of the bolt can be increased to make it within the specified range, and the increased bolt length can be filled by adding a thick washer (distance tube). This method is widely used in marine diesel engines.

5. Using nord-l0ck lock washer, the anti-loosening effect is very obvious. At present, this method has been widely used in marine diesel engines. The test results show that the anti-loose effect of this method is better than other anti-loose methods, and it is especially suitable for occasions with high vibration. Nord-lock lock washers are a set of two identical washers, each with a different serrated top and bottom. One side is a large tooth, and the tooth bevel angle a is greater than the thread angle of the bolt; the other side is a smaller and denser tooth. Nord-l0ck lock washers should be installed in pairs, with the large teeth facing each other, and the small teeth in contact with the nut and the coupling. After tightening the bolt and nut, when vibration occurs, the large tooth surface will be staggered and lifted. The principle of bolt and nut will be locked. The angle of the tooth slope is greater than the helix angle of the bolt, so it cannot be loosened;

6. Self-locking nuts are used to prevent loosening. Self-locking nuts are generally divided into non-metal (nylon) insert self-locking nuts and all-metal self-locking nuts. The working temperature of non-metallic plug-in self-locking nuts is -50c-120c, and the working temperature of all-metal self-locking nuts is -50c-300c.