Flat cushion or spring cushion? How to choose for bolts?

In the process of bolt use, flat cushion and spring cushion play an indispensable role respectively, so how to choose? Let's talk about it today.

01

Flat cushion

How to choose flat cushion?

Flat cushion is used as a part to prevent bolt and nut locking. In the use of fasteners will be used in the place of flat cushion, how to choose a suitable flat cushion? Flat cushion is a kind of flat cushion, which is mainly used to increase the contact area between screws and some large-scale equipment and tighten them. When using flat cushion, it is often suitable for nuts and nuts to cooperate with each other. When storing flat cushion, it must be within the most effective sealing time and have essential important characteristics:

1. In the harsh environment, the flat cushion should be sealed, when a certain temperature and pressure in the working time is not easy to occur leakage.

2. In the flat cushion and contact surface connection, to better ensure the sealing, just like a good effect.

3. When the cushion receives the pressure, under the influence of temperature, the anti wrinkle ability should be better, otherwise the screw will be damaged, and there will be hard gas leakage.

4. Don't get infected when using flat cushions.

5. The use of flat cushion can be very good disassembly, this is the biggest role of choosing flat cushion.

6. Remember to use the flat cushion at a relative temperature.

In order to better use the flat cushion, when choosing the flat cushion, we should try our best to choose the flat cushion with anti rust and anti-corrosion material, which not only saves time and effort, but also plays a good role in flat cushion.

When used with bolts and nuts, the selection standard of flat cushion is as follows:

1. When choosing cushion materials, attention should be paid to the electrochemical corrosion of different metals in contact. The material of flat cushion is generally the same as that of the connected parts, usually steel, alloy steel, stainless steel, aluminum alloy, etc. Copper and copper alloy can be used when there is a requirement for electrical conductivity.

2. The inner diameter of the flat cushion shall be selected according to the larger diameter of the thread or screw. The outer diameter of the connected material (such as composite material) or matching with the spring cushion should be larger.

3. When w-cushion is placed on the bolt or screw head, flat cushion with inner hole chamfer can be selected to avoid interference between fillet under head and cushion.

4. For important bolts with large diameter or in order to increase the anti extrusion ability, steel cushion should be used. Steel cushion shall be used for tension bolt or tension shear composite bolt connection.

5. Special cushion can be used in special requirements, such as copper cushion for conducting electricity and sealing cushion for air tightness.

When used with bolts and nuts, the selection standard of flat cushion is as follows:

1. When choosing cushion materials, attention should be paid to the electrochemical corrosion of different metals in contact. The material of flat cushion is generally the same as that of the connected parts, usually steel, alloy steel, stainless steel, aluminum alloy, etc. Copper and copper alloy can be used when there is a requirement for electrical conductivity.

2. The inner diameter of the flat cushion shall be selected according to the larger diameter of the thread or screw. The outer diameter of the connected material (such as composite material) or matching with the spring cushion should be larger.

3. When w-cushion is placed on the bolt or screw head, flat cushion with inner hole chamfer can be selected to avoid interference between fillet under head and cushion.

4. For important bolts with large diameter or in order to increase the anti extrusion ability, steel cushion should be used. Steel cushion shall be used for tension bolt or tension shear composite bolt connection.

5. Special cushion can be used in special requirements, such as copper cushion for conducting electricity and sealing cushion for air tightness.

02

Spring cushion

Function of spring cushion:

1. The function of spring cushion is that after tightening the nut, the spring cushion gives the nut an elastic force to tighten the nut so that it is not easy to fall off. The basic function of the spring is to give a force to the nut after tightening the nut to increase the friction between the nut and the bolt.

2. In general, it is not necessary to use the spring cushion to protect the surface.

3. Flat cushion is generally used in the connector, one is soft, the other is hard and brittle, its main role is to increase the contact area, disperse pressure, to prevent the soft texture from being crushed.

advantage:

① The spring cushion has good anti loosing effect;

② The spring cushion has good anti-seismic effect;

③ Low manufacturing cost;

④ It's easy to install.

Disadvantages:

Spring cushion is greatly affected by material and process. If the material is not good, heat treatment is not good, or other processes are not in place, it is easy to crack. Therefore, reliable manufacturers must be selected.

03

When to use flat cushion and when to use spring cushion?

1. In general, flat cushion can be used only when the load is small and does not bear vibration load.

2. Under the condition of large load and bearing vibration load, flat cushion and spring cushion must be used.

3. Basically, spring cushion is not used alone, but combined.

In the actual use process, due to the different emphasis of flat cushion and spring cushion, the two are used together in many occasions, which can protect parts, prevent nut loosening and reduce vibration at the same time, which is a great choice.