Abstract: Small-diameter vitreous cylinders, for example glass tubes, are maintained under lateral (radial) compression and are precision rolled through grinding wheels, thus fully separating the cylinders into as many cylindrical components as desired. The rolling is effected by maintaining several glass cylinders in laterally-adjacent relationship between a drive roller and a pressure sheet, the latter being under very substantial tension. Thin grinder wheels extend through slots in the pressure sheet and thereby grind completely through the rolling cylinders. The drive roller and pressure sheet continue to roll the substantially separated cylinders, in precise synchronism, so that there is no breaking but instead only grinding.

Abstract: A chlorinator for swimming pool systems which releases a charge of chemical in response to the pressure differences generated by the circulating pump. The time during which the discharge valve is open is automatically varied in accordance with the pump pressure in a flow line by way of a trip device.