Main points of automobile brake booster shell production (2)

The protruding part in the middle of the booster shell is the cavity for installing the booster push rod, vacuum valve, etc. It requires high dimensional accuracy. Generally speaking, it can be achieved by four to six punching according to the requirements of the drawing. First of all, the most important thing is to make sure that it is divided into several stampings, because too many folds in the bottom plane of the raised part are not conducive to the flatness of the next process, and the wall thickness of the stretched tube will become thinner and exceed the tolerance. Generally speaking, the thinning rate should not be less than 0.8, that is to say, if the thickness of the raw material is 2.0mm, the thinnest part after stretching can not be less than 1.6mm. The strength must ensure the safety of the pressure of the vacuum booster pump designed by the manufacturer. The detection method is generally cut in four or eight directions, and every thousand pieces of the same process have to be tested. This is the main point of the booster shell protruding molding. We will talk about the problem of the booster shell later, press As an example, a protrusion with an inner diameter of 50mm should be divided into 5 stampings. The forming diameters of the five stampings are 140mm, 100mm, 70mm, and 50mm+. Finally, the inner diameter is within the normal tolerance of 50mm. The diameter difference of the five punches is getting smaller and smaller. The reason is that there is more preform at the beginning of the maximum diameter, and the later diameter is so small that there is enough preform to achieve the purpose of bulging and not getting thinner, so the diameter difference should be small. Previous: Production points of automobile brake booster shell (1)