There are several methods for restoring springs that have lost their elasticity and ceased to perform their functions. These are thermomechanical and electromechanical methods. In addition to them, a simpler way is often chosen - "tired" springs are simply replaced with new ones.
Necessary
- - vice;
- - oil bath with AC-8 oil;
- - lathe;
- - electric transformer
Instructions
Step 1
To restore the elasticity of the springs using the thermomechanical method, place the spring in a vise and with the help of them compress the spring so that its turns are in contact with each other. Then pass an electric current of 200-400 amperes through the spring for 20-30 seconds. Select the current strength and exposure time experimentally depending on the size of the part being restored or scientifically, calculating the values of the parameters required to heat the spring to 800-850 degrees. Visually, this temperature is determined by the fact that when it is reached, the metal turns red from heating.
Step 2
After heating to the desired temperature, turn off the electric current and begin to loosen the vise so that the spring begins to slowly stretch. After the part has stretched to its maximum length, fix the end ends of the spring on the vise jaws in any way and stretch the spring by 20-30% of its standard length. The entire stretching process must last at least 30 seconds. When finished, harden the spring by placing it in an oil bath. In this case, it is best to use an oil of the AC-8 type.
Step 3
Use a lathe to restore the spring electrochemically. Place the mandrel in the lathe chuck. Secure the spring to it with a clamp. In the tool holder of the machine, install a mandrel with a deforming roller made of heat-treated steel ШХ15, hardness 60-62 HRC. On the guides of the machine bed, attach a rack with sliding rollers and rigidly connect it to the lathe support. Squeeze the mandrel with the spring pre-installed on it, the rear center, which is located in the tailstock quill.
