Common Production Problem & Die/Mould Analysis

In the process of aluminum extrusion, non-conforming products are likely to be caused by mold. So it’s necessary to conduct mould analysis. Here we list several common problems and corresponding countermeasures.

1. Cover halves combine imprecisely and have a big gap.
2. The mold clamping force is not enough.
3. The die-casting machine is flexible, and the mounting plates of cover half (fixed die) are not parallel.
4. Support span is large, and the injection pressure (force) deforms the sleeve plate, engendering molten metal spouting.

Methods of adjustment:

1. Reinstall the mold.
2. Increase the mold clamping force.
3. Adjust the die-casting machine, ensure the mounting plate of cover half (fixed die) and moving die maintain mutual parallel.
4. Add support plate on the movable mold, increase the stiffness of the clearing.

1. The material and quality of the nozzle jet.
2. The fit clearance of the press charging barrel and jet nozzle.
3. The concentricity of the mold and press charging barrel while installing.
4. Cooling problem.
5. Select and use the superior nozzle jet lube etc.

Symptom: The irregular folds emerging on the surface of the product, mainly appearing on the thinner wall.

The small aluminium granule can be seen: Owing to in drawing the release agent or compressed air, air pressure being sealed up in the forepart is high then jack up the surface of the product and result in this phenomenon.

Solution: Exhaust through going, eliminate the extra mold lubricant, adjust the position of the high speed, high pressure to prevent the Melton metal cooling down.

Symptom: The cylinder part around the insert, the surface membrane demolish appearing crumpling up, it is different according to the occurring condition. Near the corner of the insert, appearing the parallel wrinkle with the insert. A little far away from the corner. The surface membrane details can see the aluminium granule gathered, appearing in power attached to the surface cut can see the concave-convex, the wee aluminium granule embedding into the wrinkle after crushed.

Reason: when die casting with the low temperature of the mold is easy to occur this, the molten aluminium flowing in the passageway the forepart cooled and form oxide membrane details, then occur solidification at the further as due to the high pressure appearing wrinkle on the surface.

Solution: Preheat of the mold and produce under the settled temperature, should control the temperature of the mold in the appropriate scope.

Exchange the guide pillar or guide sleeve should notice the change in the size, especially the mold that is used for a long time without tempering or measured including the mold plate parallel, straightness, change of internal and external diameter. Normally the reference dimension will exchange.

Zink die pressed casting blank is no hard spot, but when polish before electroplating the hard spot occur. What’s wrong?

Notice:

1. The quality of material (degree of purity)
2. Refine to degassing and degassing when melting
3. Adjust the speed and pressure when die-casting
4. The pressure and temperature of the friction cannot be too high.