The following two points are the precautions of Zhejiang Taixing electromechanical technology

     1、 The stretching amount should be controlled at about 1%. For example, the stretching amount of 25m aluminum alloy profile should be stretched at about 25cm after straightening the profile, but it must not exceed 2%. During the production, it should be adjusted according to the actual situation of aluminum kneading profile discharge and various specific needs (opening size, appearance quality, shape size, inner diameter size, wall thickness, elongation, etc.), so as to seek the drawing amount that can satisfy various specific needs at the same time in the opposite skill needs. If the drawing amount is too high, there will be head, middle and tail scale error, water like twist (fish scale) mark on the surface, low elongation, high hardness and brittle (low plasticity). Too low drawing amount will make the compressive strength and hardness of the profile low, even aging (quenching) can not improve the hardness, and the profile is easy to curve (commonly known as big knife bending).

     2、 In order to control the tensile deformation and the dimension change of the whole profile, it is necessary to select appropriate special clamps and appropriate methods. In particular, the opening material, arc material, cantilever material, and zigzag shape of the profile should pay more attention to the reasonable and useful use of stretch clamp pad. If necessary, the center of the extruded profile should be controlled and held by a person to ensure that the stretching dimensions between the head, middle and tail sections meet the requirements of the aluminum alloy profile.