Cosden Technology, Inc.

Permian Research Corporation

Raleigh N Rutledge

Granville J Hahn

Jackie D Murley

Alonzo H Searl

Marion Johnson

Bob Joe Cruson

Carl Blanchard

Durward Rutledge

Edward Hart

Walter E Sommerman

Rotary extruder apparatus is provided comprising housing (22), recess (29) within housing (22), cylindrical rotor (30) rotatably mounted within recess (29) in housing (22), feed inlet (25), discharge outlet (52) providing fluid communication between recess (29) and diehead (26), in combination with gear pump (160) adapted to increase the pressure of material received from discharge outlet (52). Knurled rotor (30), undercut feed inlet (25), segmented rotor shafts (18, 18'), thrust rings (109, 109') made of dissimilar metals, and circumferentially spaced cartridge heaters (63) in housing (22) are also disclosed.

Rotary extruder with a gear pump

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

An injector device for use in forming multilayer extrusions of plastic resins and a method for forming such extrusions. The apparatus includes an injector member that divides the extrudate from the first extruder into two layers and receives at least one extrudate from an additional extruder that is interposed by the injector member between the divided layers of the extrudate from the first extruder. The process includes producing plasticized resin by a first extruder, dividing the extrudate into two layers, producing extrudate from a second extruder, and injecting such extrudate between the two layers of the first extrudate.

Apparatus for forming multilayer thermoplastic resin extrusions

Disclosed is an apparatus for extruding thermoplastic compositions comprising an extruder, a die, and a cooling device positioned between the extruder and the die for cooling the heat plastified resinous composition exiting from the extruder to a uniform temperature desired for extrusion through the extrusion die. The cooling device includes at least one enclosed flow path for conveying the resinous composition from the inlet of the cooling device to the outlet of the cooling device, structure for circulating a cooling medium about the entire circumference of each of the resin flow paths, and flow control orifices at the inlet and the outlet of the cooling means across the entire cross-section of each of the resin flow paths.

Apparatus for extruding thermoplastic compositions

Apparatus is disclosed for the formation of pipe comprising one or more layers of thermoplastic resin. The apparatus comprises a die housing having a bore therethrough with a mandrel longitudinally supported within the bore by radial members extending from the inside surface of the bore to provide an annular extrusion passageway defined by the inside surface of the housing and the outer surface of the mandrel. The housing includes therein a plurality of electrically resistive heating elements longitudinally positioned parallel to the extrusion passageway to selectively heat the thermoplastic material flowing therethrough in proximity to the heated section thereby increasing the laydown of thermoplastic material. Also included in the housing is plurality of radially adjustable elements having electrically resistive heating elements therein to radially reposition a moveable discharge sleeve held therebetween thereby controlling the wall thickness of the thermoplastic material passing in proximity thereto. The extrusion passageway is constricted downwstream of the radial support but prior to the annular sequentially positioned feed rings to reunite the thermoplastic material after the flow disruption created by the radial support members. Also included in the mandrel is a central longitudinal passageway in communication with the inlet section of the bore for the transportation of thermoplastic material therethrough to one or more of the annular feed rings. The mouth of the mandrel bore includes a restrictor orifice therein to balance the pressure differential created therein by the constriction in the extrusion passageway.

Extrusion apparatus for producing thermoplastic pipe

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.

Process and apparatus for manufacturing flexible foamed articles

A process is disclosed for the formation of pipe comprising one or more layers of thermoplastic resin whereby an annular stream of thermoplastic material is transported through an annular extrusion passageway. The downstream annular portion of the extrusion passageway has a radially movable outer wall. The outer wall is radially moved by heat expansion of a bolt thereagainst to change the thickness of a particular arcuate section of the stream. The thickness of the particular arcuate section of the stream may be further changed through selectively heating by electrical resistive elements an arcuate section of the extrusion passageway to heat the stream of thermoplastic material transported in proximity thereto.

Extrusion process for producing thermoplastic pipe

Disclosed is a multiple heat exchanger system utilizing an inlet manifold to distribute the flow of thermoplastic material from an extruder to the inlet ends of each of the heat exchangers, and a discharge manifold to converge the flow of thermoplastic material from the discharge ends of each of the heat exchangers and to direct the flow to an extrusion die. The inlet and outlet manifolds include a main port in communication with a plurality of passageways within the manifold to allow flow between a main conduit in communication with the main port and a plurality of distribution conduits in communication with each of the heat exchangers. A flow control means positioned at each distribution port includes a sleeve, having a flow space therethrough, axially aligned within both the distribution port and distribution conduit. The distribution conduit includes a plurality of orifices about the circumference thereof in communication with the heat exchanger for the flow of thermoplastic material. The sleeve includes a plurality of flow control orifices about the circumference thereof for the flow of thermoplastic therethrough. Communication of varying portions of the sleeve flow orifices with the distribution orifices by axial movement of the sleeve regulates the flow of thermoplastic material into and out of the heat exchanger.

Multiple heat exchanger distribution apparatus

An apparatus for the formation of a multiple layered pipe comprising a die housing having a bore therethrough with a mandrel longitudinally supported within the bore by a spider to provide an annular extrusion passageway defined by the inside surface of the housing and the outer surface of the mandrel. The mandrel comprises a series of sequentially positioned annular feed rings for the laydown of thermoplastic material on the inner surface of the main thermoplastic material flowing thereover through the extrusion passageway. The extrusion passageway is constricted downstream of the spider but prior to the annular sequentially positioned feed rings to reunite the thermoplastic material after the flow disruption created by the spider. Also included in the mandrel is a longitudinal passageway in communication with the inlet section of the bore for the transportation of thermoplastic material therethrough to one or more of the annular feed rings. The mouth of the mandrel bore includes a restrictor orifice therein to balance the pressure differential created therein by the constriction in the extrusion passageway.

Coextrusion apparatus for producing multiple layered thermoplastic pipe

A rotary extruder contains pump rings positioned at opposite ends of the rotor shaft to collect excess thermoplastic melt forced outwardly to the housing ends and to redirect this excess melt to the feed section of the extruder. Redirection of the melt is accomplished by helical grooves located on the inside surfaces of the pump rings having an axial component directed toward the center of the extruder to provide a conduit for the melt. The melt is also directed by a series of angular grooves positioned circumferentially about the rotor opposite the pump rings which rotationally and axially propel the melt as the extruder rotor rotates. The rotor shaft is supported by bearings at opposite ends of the shaft which are offset from the axial center of the bearing housing. Repositioning of the bearing housings by rotation about their axes change the axial position of the rotor relative to the inner surface of the extruder housing thereby varying the size of the feed and compression sections of the rotary extruder to accommodate different types of thermoplastic material. A feed hopper for holding thermoplastic feed has its outlet positioned above a variable speed endless belt which discharges into the inlet of a rotary extruder, the rate of delivery to the extruder being independent upon the rotational speed of the belt. A rotary gear pump is positioned between the extruder die and the extruder housing to increase the discharge pressure into the die.

Rotary extruder

A process is disclosed for the coextrusion of a multi-layered tube whereby at least one stream of molten polymer from a single-screw extruder is passed through a die; wherein the stream is divided into two concentric streams which are balanced by varying the area of a restrictor orifice placed in the central stream. Spider lines in the outer molten stream are eliminated by the use of a second restrictor means used downstream of an open chamber for reuniting the melt, which chamber is downstream of the spider legs.

Coextrusion process for producing multiple layered thermoplastic pipe

Disclosed is a process and apparatus for extrusion of multiple-layer sheeting comprising an improved co-extrusion feedblock and valve plate for laying down co-extruded resin streams onto a main extruded polymeric resin. The new design provides advantageous external control of the layer number as well as a more refined control of layer thicknesses.

Multiple-layered sheeting apparatus

Disclosed is an apparatus and process for producing multiple-layer film or sheeting which includes an improved laydown means comprising adjustable cam-actuated control means for controlling the polymer flow and individual layer thickness.

Valve plate and feedblock design for co-extrusion apparatus and

Disclosed is a process for extruding thermoplastic resinous compositions, comprising the steps of heat plastifying the resinous composition in an extruder; cooling the heat plastified resinous composition exiting from the extruder to a uniform temperature desired for extrusion through an extrusion die, including conveying the resinous composition through at least one enclosed flow path in a cooling device, circulating a cooling medium about the entire circumference of each of the resin flow paths and controlling by the means of orifices the flow of thermoplastic at the inlet and the outlet of the cooling device across substantially the entire cross-section of each of the resin flow paths; and, extruding the cooled thermoplastic resinous composition through an extrusion die downstream of the cooling device.

Growing community of inventors

Big Spring, TX, United States of America

Raleigh N Rutledge