The wall was reduced to powder when it was
Answers
Answer:
please like my all answers
The friction between compacted ferric oxide powders and cemented tungsten carbide walls has been determined. The influence of the surface structure of the walls on powder—wall friction was studied by comparing the results obtained with polished, spark-eroded, and ground walls having grooves oriented perpendicular or parallel to the direction of sliding of the wall. Typical differences in powder—wall friction, appear to be present between ground walls with grooves oriented parallel to the direction of sliding and the other walls. The effect of wall lubrication was investigaed by covering walls with a thin film of stearic acid having a thickness in the range from 0.2 to 2.4 μm. Typical diferences are found between the cases where the coating thickness is larger and smaller than the mean particle size of the powder. In practice it follows that powder—wall friction can be reduced by grinding die walls in the axial direction and by the application of lubric