Causes Of Mold Cracks And Solutions

- Jan 26, 2021-

The cause of mold cracks.


  1-1, insufficient mold rigidity


  1-2, stress concentration at the corners of the cavity


   2. Related knowledge


  2-1. The wall thickness design of the mold is an important parameter of the mold design. Strength calculation (simple calculation of simple tension) is performed to ensure the necessary thickness of the mold. Also, additional grooves are used to utilize the overall rigidity of the mold.


  3-2, stress concentration is easy to occur when processing the corners of the cavity, and cracks are also easy to occur in this place, so the corners must be processed into a shape with a round corner R


   Three, the solution


  3-1. Process the edges and corners of the mold cavity into a rounded R shape, and process the mold parting surface into a grooved shape to strengthen and enhance the rigidity of the mold


   Four, due to differences in materials;


  4-1, there is no special reason.


  The reason why the mold is out of stock and broken


  1-1 The toughness of the release pin is insufficient


   The root radius R of the 1-2 ejector pin is incomplete.


  二、Related knowledge


  2-1 The ejector pin hole is related to the position of the mold screw on the mold, so the ejector pin is thin and


  Long, because of the molding pressure, it is easy to bend, and it is easy to break.Therefore, this kind of pin must be heat treated to have both very toughness and a certain degree of hardness.


  2-2 Because the stress concentration of the pin is mostly concentrated at the corner R of the root, if there is damage in this part during processing, it is common for the stress concentration here to break the release pin.


   Three, the solution


  3-1 demolding pins are heat treated.


  四 Due to differences in materials;


   3-1 No special reason