First, the characteristics of the spring

The characteristics of the tension spring and compression spring should be suitable: under the load of the specified height (or length), the spring deformation should be between 20% and 80% of the deformation under the test load. When the first level of precision is required, the spring should be specified The amount of deformation under high load should be above 4mm; when there is a special need to check the stiffness for characteristics, the amount of deformation should be between 30% and 70% of the amount of deformation under the test load.

Test stress τs: When calibrating spring characteristics, use the maximum allowable load on the spring as the test stress.

Test load Fs When calibrating spring characteristics, the maximum load allowed on the spring is used as the test load.

2. The limit error of the spring

In fact, the limit error of the load F at the specified height is also based.

●The limit error of the load F when the compression spring is at the specified height

among them,

(N), is the number of useful turns

≥3~10 10

±0.059

±0.049

±0.159

±0.12F

●When the useful number of turns of the tension spring is greater than 3, the limit error of the load F under the specified length is defined as follows:

±[(initial tension F0×α)+(load-initial tension F0×β at specified length]

among them,

Α refers to the limit error with the initial tension F0;

Β refers to the limit error of the load F corresponding to the deformation amount.

The initial tension of the tension spring and the limit error α and β value of the load F

The limit error of the stiffness of the tension spring and compression spring is also specified in the table.

Unit: (N/mm), refers to the limit error of spring stiffness F.