Thursday, July 8, 2010

Dry mixer

Here are a few images of the dry mixer I am currently using. This has served me very well over the years for dry mixing larger batches of glaze and other materials for use in ceramic testing.

The container is a 5-gallon bucket. The fins are made of Plexiglas which are held in place with regular angle braces, nuts and bolts. The fin design was inspired by the lowly clothes drying machine. I recently added the wire mesh as way to further promote the breakup of agglomerates.

Dry mixer

After filling with dry powders, the bucket is closed and placed on a ball mill unit where it rotates (I usually leave it running overnight).

Dry mixing bucket on the ball mill unit.

A few issues with this design:

1-There must be an optimal amount of powder. Too much powder and thorough mixing won't happen. I'm not sure what the optimum amount is for this design. I usually don't fill the container more than halfway.

2-As the bucket is slightly sloped, over time material will accumulate on one of the two ends of the container. Movement is happening axially (thanks to the fins) but not across the axis from end to end. This isn't good! Several times during a mixing cycle, I will pick up the bucket and shake it back and forth to redistribute materials. This should really happen continuously through the design of the mixer itself.

3-Pockets. The design has several corners, or pockets where material can get lodged and not flow freely. This is absolutely not good for mixing! I alleviate this by tapping the container several times during the mixing cycle. Again, this should be eliminated in a better design.

Given points 2 and 3 above, I am working on a better design...

1 comment:

  1. I like this blog it’s very informative and attractive also. Thanks to author for this post it’s very easy to understand. sheet metal fabrication companies