# The name and size relationship of each part of the spring

Springs are widely used in daily products. At present, there are five major markets for spring products, transportation, daily hardware, instrumentation and electronic appliances, industrial and mining accessories, and overseas export markets. Next, let’s take a brief look at the various parts of the spring. Name and size relationship.

(1) Talking about the diameter of the spring wire 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: In addition to the support ring, the axial distance between the corresponding points of the 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) The number of support rings n2: In order to make the spring work evenly, to ensure that 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 speaking. 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 indicated in the drawing.