How to design aluminium extrusion die bearing length(solid type section)
Bearing design is a key role in producing high quality extrusions. Balancing the flow by adjusting the bearing lengths to eliminate profile distortion is a common practice in the industry and the experience of die designers is also important.
1.When design bearing length for aluminium extrusion die,first of all,the most difficult part will be a design base,the bearing length is 1.5-2 times of section thickness.For figure 1,the section thickness is “t”, because of its large width,extrusion will be difficult ad two ends of this section,so we choose bearing lenghth of this part as the base,L=(1.5-2)t.
2.Near the base,the bearing length will be 1mm longer than the base,as shown in figure 2.
3.For same thickness of section,if they have same distance to the extrusion container centre,the bearing length will be same.
4.Start from die centre,every 10mm the bearing length will be decreased accordingly,see figure 5.
5.Based on same conditions,the bearing length will be in proportion to its thickness,see figure 2.
6.The bearing length at screw hole will increase 1mm(see figure 3a),The bearing length will increase 1mm at the cirle (see figure 3b)
7.Because of resistance from 3 sides,the metal flow is lower,as a result the bearing length will decrease 1mm.(see figure 4)
If you have any question in working,welcome to share your experiences,we can find effective solution together.