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How Many Misunderstandings do you Know When Using Fasteners?

Jan. 05, 2021

Fasteners are a common fastener connection part in our lives, ranging from screws on watches to large mechanical parts or aircraft bolts and nuts. The use range of fasteners is very wide, but during our use, will you encounter some misunderstandings? For example, if we don't have fine-pitch bolts, can coarse-pitch bolts be used instead?

Track Bolt

Track Bolt

As a Rail Bolt Manufacturer, share with you. When using fasteners, what are the misunderstandings and how much do you know?

1. Use coarse teeth instead of fine teeth

There are many important connecting parts on the machine, such as the drive shaft, and most of the bolts are fine thread. If there are missing parts during maintenance, some maintenance personnel will use coarse bolts instead, which should be avoided.

Because the inner diameter of the fine pitch bolt is larger, the pitch and outer angle is smaller, the strength is high, the self-locking performance is good, and the ability to withstand impact, vibration and exchange loads is relatively strong. Once replaced with coarse-threaded bolts, it is easy to loosen or fall off, disassemble, and even cause mechanical accidents.

2. The pores are not matched

The bolts on the machine that bear the lateral load and shear force, such as the drive shaft bolts and flywheel bolts, are matched with the bolt holes as transitional fits. The assembly should be strong and reliable, and can withstand lateral forces. Someone does not pay attention to the inspection during the assembly process, and continues to install when there is a large gap between the bolt and the bolt hole, which is prone to bolt loose or cut off accidents.

3. Thicken nuts increase connection reliability

Some people mistakenly believe that thickening the nut can increase the number of working turns of the thread and improve the reliability of the coupling. But in fact, the thicker the nut, the more uneven the load distribution between the threads of each circle, and the easier the coupling is to loosen.

4. One female with multiple pads

After the installation is complete, sometimes the bolt is too long, so someone installs an additional spring washer on the bolt. In this case, the spring washer will break due to uneven force during the strengthening process, which will cause the bolt to be pre-tensioned. If the tightening force is reduced, eccentric load may be generated, which reduces the reliability of the bolt connection.

5. The tighter the screw, the better

Many workers have such a misunderstanding: that the bolts should be "tighter rather than loose", so they deliberately increase the tightening torque, resulting in bolt slip. In addition, some important bolts that need to be tightened with torque, some people use adjustable wrenches to save trouble. As a result, the torque is insufficient, which leads to the loosening of the bolts and even mechanical failure.

Our company also has Track Bolt on sale, welcome to contact us.