What are the methods to prevent loosening of bolts during machining?

As a fastener, bolts are widely used in power equipment, mechanical and electrical machinery and other industries. The bolt is composed of two parts: the head and the screw. It needs to cooperate with the nut to fasten two parts with through holes. Bolts are non-removable, but they will loose if they are frequently disassembled for special needs. How to ensure that the bolt does not loosen? This article will specifically introduce the bolt loosening method.

The commonly used methods for preventing loosening of bolts include friction locking, mechanical locking, and permanent locking. The first two methods are detachable locks. The permanent locking is non-removable and anti-loose. The detachable locking is made of gaskets, self-locking nuts and double nuts. This method can be used after dismantling. The commonly used permanent locking methods are spot welding, riveting and bonding and so on, this method will mostly destroy the threaded fasteners when it is disassembled and cannot be reused.

Friction locking

1.Spring washers prevent looseness: After the spring washers are assembled, the washers are flattened. It keeps the pressing force and friction between the threads to prevent looseness by the rebound force.
2.Anti-loosening of the top nut: The use of the nut top action causes the bolt type to be subjected to additional tension and additional friction. The extra nuts make work unreliable and therefore rarely used in machining.
3.Self-locking nut anti-loose: one end of the nut made of non-circular shut. When the nut is tightened, the opening is expanded and the elastic force of the closing is used to press the screw thread tightly. This method is simple in structure and is often used in bolt loosening.

Mechanical locking

1.Stopping washer: After tightening the nut, fix the monaural or binaural stop washer to the sides of the nut and the connected part to prevent loosening. Double locking washers can also be used to achieve double locking of the two bolts.
2.Series steel wire anti-loose: Use low-carbon steel wire to penetrate the holes in the head of each screw, and connect the screws in series to allow them to brake each other. This structure requires attention to the direction in which the wire is threaded.

Permanent locking

1.Anti-loose by the punching method: After the nut is tightened, the thread breaks the thread at the end of the thread.
2.Adhesion prevention: The anaerobic adhesive is applied on the screw threading surface. After the nut is tightened, the adhesive can be cured by itself and has a good anti-loosening effect.

The above methods are commonly used in production and processing to prevent loosening of bolts. In daily processing, it is necessary to select a suitable method for preventing looseness according to actual conditions.

Wuxi Lead Precision Machinery Co., Ltd offers customers of all sizes complete custom metal fabrication services with unique processes.

Post time: Jan-07-2021