Abstract: Small workpieces to be coated with plastic material are preheated and dropped onto a fluidized bed of plastic powder subjected to compound vibratory motion which causes the powder and the workpieces to move along a helical ramp onto a screen overlying the point of entry, with some of the particles fusing onto the workpiece surfaces to form a film. The remainder of the powder, on reaching the screen, drops back onto the bed as the coated workpieces move on to a receptable. Fresh workpieces are deposited on the bed through one or more chutes traversing the screen; to prevent the rise of any particles through the chutes, a downward airflow is created therein.

Abstract: A viscometer comprises a liquid feeding conduit opening into a measuring chamber and a capillary liquid outlet conduit connected to said chamber, pressure-sensitive means associated with said chamber for sensing the pressure variations in the latter, converting means for converting the pressure variations sensed by said pressure sensitive means into measurable and displayable quantities of value, said feeding and capillary conduits and said pressure-sensitive means being enclosed in a metallic block arranged in a heat-insulated space which includes heating means for heating said block, said heating means being adapted to maintain the temperature of said block at an adjustable predetermined value.

Abstract: The instant invention relates to a method for purifying lactams wherein the lactam to be purified is contacted in the fused state with inorganic adsorption agents.The said method comprises contacting the lactam to be purified in the fused state with an inorganic adsorbent, then separating the lactam from the adsorbent and regenerating said adsorbent if desired, wherein said adsorbent is impregnated with at least one impregnation compound selected from the group consisting of an acid and the alkali metal salts which are thermally stable and exert no action on the lactam at temperatures lower tha 250.degree.C.