Spring is a mechanical parts that use elasticity to work. Spring is a kind of elastic element widely used in the mechanical and electronics industry. When the spring can produce greater elastic deformation when loading and transform mechanical work into deformation energy. After unloading, the deformation of the spring disappears and returns to the original state. At the same time, the deformation energy is converted into mechanical energy. The ratio of the load to deformation of the spring is called the spring stiffness. The greater the rigidity, the harder the spring.
Function of Spring
Cushion and Damping
For example, the damping spring under the car and the train, the buffer spring of various buffers.
Control the movement of the mechanism
Such as the valve spring in the internal combustion engine, the control spring in the clutch, etc.
Storage and output energy.
Such as clock springs, gun latch springs, etc.
Such as spring scale, dynamometer spring, etc.
Manufacturing of Spring
The manufacturing process of the spring includes: rolling, hook fabrication, and fine finishing, heat treatment and process performance test of the end-surface ring.
When producing a large amount, spring is rolled on the universal automatic roll spring machine. When producing in single and small batches, it is made in general lathes or handmade. When the diameter of the spring wire is less than or equal to 8mm, the cold coiling method is commonly used. When the diameter is greater than 8mm, the hot coiling method is adopted and the temperature of the hot coiling is 800 ° C to 1000 ° C. After the hot rolling, it is quenched and medium-temperature tempering. The surface quality test should be performed after the spring is shaped. The surface should be smooth and clean without scars, decarburization and other defects.
Causes of Spring Failure
The stress generated by the external load is greater than the yield strength of the material. The spring can’t be restored to the original size and shape.
Under the action of alternating stress, generate surface defects and crack fatigue.
Rapid brittle fracture
Some spring has material defects, processing defects, heat treatment defects, etc. When subjected to a large impact load, sudden crispy breaks occur.
The spring used in the corrosive medium is prone to cause stress corrosion cracking fracture. Spring accessories used at high temperature are prone to creep and stress relaxation, producing permanent deformation.
Precautions for Spring
In actual work, even if the compression spring is subjected to a force beyond the elastic limit of the material, it should maintain its working length. Therefore, the length of the finished spring should be equal to the calculation length of the spring plus the initial compression volume, which can avoid the inadequate spring. In the process of heat treatment for the finished spring. Especially for the springs which require quenching, hardening and tempering process, spring must be placed in the furnace to prevent the springs from shortening due to its own weight, which may lead to improper operation.
Deformation application of spring
Spring collet, also known as spring sleeve, which is one of the deformation applications of spring, can provide fast and high accuracy positioning, clamp fastening motion on work pieces.
Advantages of spring collet
1. It is very suitable for the processing of workpieces with small diameter.
2. It can realize fast loading and unloading.
3.The replacement time is very short, which can realize the rapid replacement of fixtures of different sizes
4.Higher clamping accuracy compared with chuck
5. It can saves costs and has higher flexibility than chuck
6. For the machine tool with internal interpolation spindle structure, the spring collet can provide the shortest cutting force, which has a larger processing space and processing rigidity than chuck.
7. It can better protect the surface of the workpiece and provide better cutting torque.
The article mainly provides some useful tips to better learn and use the spring, such as the functions, causes of failure, deformation application.