American Standard snake spring

The heat treatment process of the snake type spring:

1,the first quenching,tempering:the first tempering and tempering of the snake type spring is to adjust the structure of the steel plate.The ssert spring blank is 145.5mm x 14.5mm x 3mm plate.Each batch has 3%samples.The blank and sample are loaded into the sling.It is heated in the salt bath furnace and the oil is cold.

The tempering parts should be cleaned,skimmed,sandblasting,and coated with protective coatings on the surface of the parts and samples.The tempering temperature is 720 C 10 C,the heat preservation is 60min,the air is cold,and the hardness is HRC26.

2,intermediate annealing:the serpentine spring is first annealed for intermediate annealing.Before the intermediate annealing,the protective coating should be applied before coating.After annealing,the residual iron coating can be removed by slight sand blasting,and then the final shape will be formed.

3,the second quenching and tempering:the purpose of second quenching and tempering of snake spring is to shape the final performance of the parts.After the final forming,the steel wire is bound up and heated and then cooled through the fully deoxidized salt bath.Water cleaning with 60~80 degrees of oil quenching,then 425-10 Deg.C tempering,tempering the specimen surface abrasion test hardness more than 0.2mm should be HRC49~51.

4,the last tempering:after testing the snake spring hardness is qualified,the parts are processed by sandblasting,and then pre treated.The pressure is measured to 55mm+1mm at the actual measurement position,30~40h is maintained,and then the final tempering is carried out.