**A spring** is a mechanical part that uses elasticity to work. Generally made of spring steel. It is used to control the movement of parts, alleviate impact or vibration, store energy, measure the size of force, etc. It is widely used in machines and meters. According to the shape, there are mainly __spiral springs, leaf springs, scroll springs and so on.__

Functions and applications ①Control the movement of machinery, such as valve springs in internal combustion engines, control springs in clutches, etc. ② Absorb vibration and impact energy, such as buffer springs under cars and trains, and vibration-absorbing springs in couplings. ③Store and output energy as power, such as clock springs, springs in firearms, etc. ④Used as a force measuring element, such as a dynamometer, a spring in a spring scale, etc. The ratio of spring load to deformation is called spring stiffness. The greater the stiffness, the harder the spring.

Generally speaking, the materials for springs should have high elastic limit, fatigue limit, impact toughness and good heat treatment performance. Commonly used are carbon spring steel, alloy spring steel, stainless spring steel, copper alloy, nickel alloy and rubber. Wait. There are cold-rolling methods and hot-rolling methods for manufacturing springs. Some springs need to be subjected to strong pressure or shot peening after they are made, which can improve the load-bearing capacity of the springs. __A spring is an elastic element widely used in the machinery and electronics industries. The spring can produce greater elastic deformation when loaded, converting mechanical work or kinetic energy into deformation energy, and the deformation of the spring disappears and returns to its original shape after unloading. Convert deformation energy into mechanical work or kinetic energy.__

**Types of springs:**

According to the nature of the force, springs can be divided into extension springs, compression springs, torsion springs and bending springs; according to their shapes, they can be divided into disc springs, ring springs, leaf springs, spiral springs, truncated cone scroll springs and torsion bar springs, etc. . Ordinary cylindrical springs are the most widely used because they are simple to manufacture, can be made into various types according to the load conditions, and have a simple structure. Generally speaking, the materials for springs should have high elastic limit, fatigue limit, impact toughness and good heat treatment performance. Commonly used are carbon spring steel, alloy spring steel, stainless spring steel, copper alloy, nickel alloy and rubber. Wait. There are cold-rolling methods and hot-rolling methods for manufacturing springs. Some springs need to be subjected to strong pressure or shot peening after they are made, which can improve the load-bearing capacity of the springs.

**What is a coil spring?**

helical spring is a torsion spring, which is a spring that undergoes torsional deformation, and its working part is also tightly wound into a spiral shape. The end structure of the torsion spring is a torsion arm machined into various shapes, not a hook ring. Torsion springs are often used in balancing mechanisms in machinery, and are widely used in industrial production such as automobiles, machine tools, and electrical appliances.

**What is a tension spring?**

Extension springs are helical springs that bear axial tension. Extension springs are generally made of round cross-section materials. When not under load, the coils of the tension spring are generally tight and there is no gap.

**What is a compression spring?**

Compression springs are helical springs that bear the pressure. Most of the materials used are circular in cross-section, and they are also rolled with rectangular and multi-stranded steel coils. The springs are generally of equal pitch. The shapes of compression springs are: cylindrical, conical There is a certain gap between the coils of the compression spring, such as the shape, the convex shape and the concave shape, and a small amount of non-circular shapes. When the spring is subjected to an external load, the spring shrinks and deforms to store the deformation energy.

**What is a torsion spring?**

The torsion spring uses the principle of lever to twist or rotate the elastic material with soft material and greater toughness, so that it has great mechanical energy.

**Name of each part of the spring:**

(1) Spring wire diameter d: the diameter of the steel wire used to make the spring.

(2) Spring outer diameter D: the maximum outer diameter of the spring.

(3) Spring inner diameter D1: the minimum outer diameter of the spring.

(4) Spring diameter D2: the average diameter of the spring. Their calculation formula is: D2 = (D + D1) ÷ 2 = D1 + d = D-d

(5) t: Except for the support ring, the axial distance between the corresponding points of two adjacent coils of the spring on the pitch diameter becomes the pitch, which is represented by t.

(6) Effective number of turns n: The number of turns that the spring can maintain the same pitch.

(7) Number of support circles n2: In order to make the spring work evenly, to ensure that the end of the axis is perpendicular to the end surface, the two ends of the spring are often tightened during manufacturing. The number of tight turns only serves as a support and is called a support ring. Generally there are 1.5T, 2T, 2.5T, and 2T is commonly used.

(8) Total number of turns n1: The sum of the effective number of turns and the support ring. That is, n1=n+n2.

(9) Free height H0: The height of the spring without external force. Calculated by the following formula: H0=nt+(n2-0.5)d=nt+1.5d (when n2=2)

(10) Spring unfolding length L: The length of the steel wire required to wind the spring. L≈n1 (ЛD2)2+n2 (compression spring) L=ЛD2 n+ hook extension length (tension spring)

(11) Helix direction: there are left and right rotations, right-handed is commonly used, and right-handed is generally used if it is not specified in the drawing.

(12) Spring winding ratio; ratio of pitch diameter D to wire diameter d

**About the effective number of turns of the spring**

** The effective number of turns refers to the number of turns that the spring can maintain the same pitch. Calculation of the effective number of coils of the spring: total number of coils — support ring, calculated according to the structure.**

For tension springs, the effective number of turns n=total number of turns n1, when n>20, the rounding is an integer turn, and when n<20, the rounding is a half turn.

For compression springs, the effective number of turns n is the total number of turns n1 minus the number of support turns n2, n2 can be obtained by looking up the table. The mantissa should be 1/4, 1/2, 3/4, or full circle, 1/2 circle is recommended.

Our popular algorithm is to subtract the total number of turns of the compression spring from the number of turns that will not be deformed by the upper and lower contact, generally 2 turns; the effective number of turns of the torsion spring and tension spring is the total number of turns.