mold on the forming machine and principles of life
Die life is defined to ensure that the premise of quality parts, mold can reach the production number (the number of stamping, molding the number). It includes repeated grinding and replacement of wearing parts, until the mold forming the main part of the replacement of the total number of qualified parts.
Mold life: the number of molds have been produced. The failure of die failure are divided into non-normal and normal failure. Non-normal failure (early failure) is not mold up to a certain level of industry recognized when life can not work. Form of early failure of the plastic deformation, fracture, severe wear and tear, such as partial. Die failure is the normal means used by the high-volume production, because of the slow plastic deformation or wear more evenly or fatigue fracture, while those unable to work.
1. Die a normal life
Die before the normal failure to produce the number of qualified products, called the normal mold, or die life, dies before the first repair to produce the number of qualified products, called the first time in life; die after a repair before the next repair qualified to produce the number of products, called repair mode life. Mold life is the first life and the life of the times the sum of repair.
2. Mold form and the principle of Failure
Mold a wide range of working forming machine conditions vary greatly, the damage is also different, but failure can be summarized in the form of three or less, that is, wear, fracture, plastic deformation.
Wear Failure
Die at work, contact with the forming blank, resulting in relative motion. Relative motion due to the surface, gradually losing contact with the surface material is called wear and tear phenomenon. Wear Failure can be divided into the following categories:
Fatigue wear a.
Relative motion between contact surfaces when the cycle of stress (mechanical stress and thermal stress) is under the surface of the phenomenon of metal fatigue as off fatigue wear.
wear and cavitation erosion wear
Metal surface rupture of the bubble, producing an instant impact and high temperature, so that micro-mold surface and pit Ma phenomenon called cavitation wear.
Tiny particles of liquid and solid impact of repeated high-speed mold surface, so that the surface of die loss of local materials, the formation of pitting and pit called the phenomenon of erosion wear.