Abstract: An apparatus for measuring hardness of materials has an indentor to be pressed into the surface of material, a rod in the form of a center plate having a shank rigidly secured to one end thereof and the indentor rigidly secured to the other end thereof. The apparatus also has a dynamometric gauge having a first branch thereof with a hole in which the shank of the rod is received. A second branch of the dynamometric gauge supports a spindle of a device for loading the indentor. One of the branches of the dynamometric gauge carries at least one pick-up for measuring the load at the indentor engageable with the other branch of the dynamometric gauge. The apparatus also has a device for measuring the depth of penetration of the indentor into the surface of material in the form of a frame having its opposed bars enclosing the first branch of the dynamometric gauge.

Abstract: An elongated, horizontal and at least partially closed air jet dispersion and air jet entrained material deceleration zone is provided and one end of the zone includes at least skewed velocity distribution nozzle of the circular Coanda surface-type opening inwardly along the zone toward the other end thereof. The zone includes discharge structure defining a plurality of downwardly opening gravity-type outlets spaced longitudinally along the zone and duct structure for flowing air and airflow entrained solids therethrough at high velocity is provided. The duct structure includes an outlet end opening into the nozzle and an inlet end open to the ambient atmosphere and positioned to receive gravity discharged solid materials from the outlet spaced one outlet from the aforementioned one end of the zone.