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Die casting production in four problem is often encountered defensive approach

Source:Fufeng Mold Industrial Group Limited    Data:2016/07/26    Hits:

Die-casting mold production often encountered gating system, overflow discharge system, the runner, defensive approach the gate, overflow tank problem

1. gating system, overflow discharge system
       ① pressure interior diameter size should be based on the desired ratio of the pressure chamber and the pressure to select fullness, while the inner diameter of the sleeve should be higher than the gate bias voltage deviation interior diameter appropriate amplification Jisi, which can avoid the sprue bushing and pressure indoor different shaft diameter caused by wear and tear or punch card dead serious problems, and the wall thickness of the sprue bush can not be too thin. The length of the sprue bush should generally be less than the injection plunger dispensing process lead to paint emerge from the pressure chamber.
      ② pressure chamber bore and sprue bush, and after heat treatment should be grinding, then grind in the axial direction, the surface roughness ≤Ra0.2μm.
      ③ splitter coating formed cavity, which is equal to the depth of the concave runner depth, with a diameter sprue bushing diameter, along the direction release 5 ° slope. When applied to import straight runner, because shortening the effective length of the volume of the pressure chamber can be increased fullness pressure chamber.
              2. For the runner mold requirements
      ① Horizontal cold runner mold should generally be located at the entrance to the inner diameter of the upper portion of the pressure chamber more than 2/3 of the site, in order to avoid the pressure chamber of molten metal under gravity into the early runners, start to solidify in advance.
      ② runner cross sectional area of the gate should be gradually reduced from the sprue until, for the emergence of cross-sectional expansion of the metal flow will be negative over time, easily inhaled gas parting surface, increasing the flow of molten metal wrapped in a vortex of gas. Usually at the outlet than the inlet cross section of 10 to 30% smaller.
     ③ runner should have a certain length and depth. The purpose is to maintain a certain length and a guide from the steady stream of action. If the depth is not enough, the liquid metal cooling fast, depth is too deep, too slow due to condensation, affecting both productivity and increase the amount of the charge back. ④ runner cross-sectional area greater than the cross-sectional area of the ingate, to ensure that the speed of the liquid metal into the type. Main runner should be larger than the cross-sectional area of each branch runner cross-sectional area.
     ⑤ on both sides of the bottom of the runner should be rounded to avoid the early cracks, second side can be made about 5 ° inclination. The surface roughness ≤Ra0.4μm runner site.
           3. the gate
     ① should not be closed immediately after parting plane into the liquid metal type, the overflow tank and exhaust ducts should not be a positive impact core. The flow of molten metal into the pattern after cast into possible along the ribs and fins by the thick padding at the thin wall and the like.
     ② choose the Internal gate position, as shortest molten metal flow. When using multi-strand within the gate, to prevent the type of molten metal after a few shares of convergence, mutual impact, resulting vortex vadose oxide inclusions and other defects.
     Ingate thick pieces ③ thin-walled parts should be appropriate smaller, in order to ensure the necessary fill speed, the gate should be set for easy removal without the casting of a defective body (meat).
           4. overflow tank
     ① the overflow tank to facilitate removal from the casting, casting and try not to damage the body.
     When opening the exhaust groove ② overflow tank, should pay attention to overflow position, to avoid premature blocking exhaust groove, the exhaust groove does not work.
     ③ should open a few ports on the same overflow overflow tank or open a very wide and thick overflow, in order to avoid liquid metal cooling liquid, slag, gas, paint and other return cavity from the overflow tank causing casting defects. Die-casting mold production often encountered gating system, overflow discharge system, the runner, defensive approach the gate, overflow tank problem
             1. gating system, overflow discharge system
       ① pressure interior diameter size should be based on the desired ratio of the pressure chamber and the pressure to select fullness, while the inner diameter of the sleeve should be higher than the gate bias voltage deviation interior diameter appropriate amplification Jisi, which can avoid the sprue bushing and pressure indoor different shaft diameter caused by wear and tear or punch card dead serious problems, and the wall thickness of the sprue bush can not be too thin. The length of the sprue bush should generally be less than the injection plunger dispensing process lead to paint emerge from the pressure chamber.
      ② pressure chamber bore and sprue bush, and after heat treatment should be grinding, then grind in the axial direction, the surface roughness ≤Ra0.2μm.
      ③ splitter coating formed cavity, which is equal to the depth of the concave runner depth, with a diameter sprue bushing diameter, along the direction release 5 ° slope. When applied to import straight runner, because shortening the effective length of the volume of the pressure chamber can be increased fullness pressure chamber.
              2. For the runner mold requirements
      ① Horizontal cold runner mold should generally be located at the entrance to the inner diameter of the upper portion of the pressure chamber more than 2/3 of the site, in order to avoid the pressure chamber of molten metal under gravity into the early runners, start to solidify in advance.
      ② runner cross sectional area of the gate should be gradually reduced from the sprue until, for the emergence of cross-sectional expansion of the metal flow will be negative over time, easily inhaled gas parting surface, increasing the flow of molten metal wrapped in a vortex of gas. Usually at the outlet than the inlet cross section of 10 to 30% smaller.
     ③ runner should have a certain length and depth. The purpose is to maintain a certain length and a guide from the steady stream of action. If the depth is not enough, the liquid metal cooling fast, depth is too deep, too slow due to condensation, affecting both productivity and increase the amount of the charge back. ④ runner cross-sectional area greater than the cross-sectional area of the ingate, to ensure that the speed of the liquid metal into the type. Main runner should be larger than the cross-sectional area of each branch runner cross-sectional area.
     ⑤ on both sides of the bottom of the runner should be rounded to avoid the early cracks, second side can be made about 5 ° inclination. The surface roughness ≤Ra0.4μm runner site.
           3. the gate
     ① should not be closed immediately after parting plane into the liquid metal type, the overflow tank and exhaust ducts should not be a positive impact core. The flow of molten metal into the pattern after cast into possible along the ribs and fins by the thick padding at the thin wall and the like.
     ② choose the Internal gate position, as shortest molten metal flow. When using multi-strand within the gate, to prevent the type of molten metal after a few shares of convergence, mutual impact, resulting vortex vadose oxide inclusions and other defects.
     Ingate thick pieces ③ thin-walled parts should be appropriate smaller, in order to ensure the necessary fill speed, the gate should be set for easy removal without the casting of a defective body (meat).
           4. overflow tank
     ① the overflow tank to facilitate removal from the casting, casting and try not to damage the body.
     When opening the exhaust groove ② overflow tank, should pay attention to overflow position, to avoid premature blocking exhaust groove, the exhaust groove does not work.
     ③ should open a few ports on the same overflow overflow tank or open a very wide and thick overflow, in order to avoid liquid metal cooling liquid, slag, gas, paint and other return cavity from the overflow tank causing casting defects.