Cosden Technology, Inc.

Alonzo H Searl

Granville J Hahn

Raleigh N Rutledge

Walter E Sommerman

Process and apparatus are disclosed for manufacturing foamed articles such as tubes used as pipe insulation, which tubes are of a high impermeability and flexibility and are formed of a polymer, such as polyethylene or polypropylene, containing up to as much as 50% of an elastomer.

Foamed polymer tubing

Disclosed is heat exchange apparatus for controlling the temperature of a resin after leaving an extruder and prior to extrusion through a die in an extrusion process, comprising a heat exchanger having an inlet and outlet for an extruded heat-plastified resin and an inlet and an outlet for a heat exchange medium to be circulated in heat exchanging relationship with the extruded resin; a selective heater for receiving the heat exchange medium from the heat exchanger, the heater heating the heat exchange medium to a predetermined temperature during a start-up phase of the heat exchange device; a cooler adapted for receiving a portion of the heat exchange medium from the heater, the cooler including an inlet and an outlet for the heat exchange medium and an inlet and an outlet for a cooling medium to be circulated in heat exchanging relationship with the heat exchange medium; control means interposed between the heater and the cooler for selectively directing a portion of the heat exchange medium to said cooler in response to a sensed temperature condition and for directing the balance of the heat exchange medium to the heat exchanger; and a pump for circulating the heat exchange medium between the heat exchanger, the heater, and the cooler.

Heat exchanger apparatus for extruding thermoplastic compositions

Process and apparatus are disclosed for manufacturing foamed articles such as tubes used as pipe insulation, which tubes are of a high impermeability and flexibility and are formed of a polymer, such as polyethylene or polypropylene, containing up to about 25% of an elastomer.

Growing community of inventors

Fort Worth, TX, United States of America

Alonzo H Searl