Patents Assigned to Central Plastics Company
  • Patent number: 6896297
    Abstract: A gas service riser assembly and ductile pipe to plastic pipe transition connection is provided. The gas service riser assembly comprises an outer ductile pipe, a plastic pipe having open ends disposed within the outer ductile pipe and extending through one end thereof, a hollow rigid stiffener disposed within the interior of a portion of the plastic pipe within the outer ductile pipe, a gasket positioned around the exterior of the plastic pipe adjacent to the stiffener, and a crimp formed in the outer ductile pipe adjacent to the stiffener and the gasket whereby the outer ductile pipe is compressed against the gasket, plastic pipe and the stiffener to form a seal.
    Type: Grant
    Filed: August 5, 2003
    Date of Patent: May 24, 2005
    Assignee: Central Plastics Company
    Inventor: Howard Wayne Hall
  • Patent number: 5988689
    Abstract: The present invention provides improved heat-shrinkable electrofusion fittings and methods. The fittings are basically comprised of an electrically heatable tubular plastic outer member which is shrinkable when heated to a transition temperature, an electrically heatable tubular plastic inner member positioned within the outer member which has a fusion temperature higher than the transition temperature and an electrically activated induction coil for energizing the inner and outer members.
    Type: Grant
    Filed: December 26, 1997
    Date of Patent: November 23, 1999
    Assignee: Central Plastics Company
    Inventor: Ernest Lever
  • Patent number: 5988692
    Abstract: The present invention provides an improved metal to plastic pipe transition fitting. The transition fitting basically comprises a metal sleeve having a pair of metal pipe sections attached thereto and an annular groove within the interior thereof. A plastic pipe is disposed within the metal sleeve which extends through one of the metal pipe sections. The end of the plastic pipe within the metal sleeve includes a plurality of spaced plastic retention rings and a snap ring attached thereto and the snap ring is engaged within the annular groove in the metal sleeve. At least one O-ring is disposed between the retention rings on the plastic pipe and a metal stiffening insert is disposed within the end portion of the plastic pipe within the metal sleeve.
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: November 23, 1999
    Assignee: Central Plastics Company
    Inventor: Richard E. Springer
  • Patent number: 5895543
    Abstract: A clamping apparatus for use in clamping a fitting to a pipe or other fitting. The apparatus may be used without supporting the outer surface of the pipe on the opposite side of the fitting, and in the case of a buried pipe, only a portion of the pipe needs to be excavated. The apparatus comprises a clamping plate for engaging an outer surface of the fitting with an adjusting stem threadingly engaged with the clamping plate. A locking bar is pivotally and rotatably attached to an end of the adjusting stem. A weight differential between long and short ends of said locking bar and a cable are used to pivot the locking bar between a first position thereof wherein the locking bar and a portion of the stem may be inserted through aligned openings in the fitting and pipe and a second position.
    Type: Grant
    Filed: April 13, 1998
    Date of Patent: April 20, 1999
    Assignee: Central Plastics Company
    Inventor: Terry L. Stiles
  • Patent number: 5798021
    Abstract: A clamping apparatus for use in clamping a fitting to a pipe or other fitting. The apparatus may be used without supporting the outer surface of the pipe on the opposite side of the fitting, and in the case of a buried pipe, only a portion of the pipe needs to be excavated. The apparatus comprises a clamping plate for engaging an outer surface of the fitting with an adjusting stem threadingly engaged with the clamping plate. A locking bar is pivotally and rotatably attached to an end of the adjusting stem. A weight differential between long and short ends of said locking bar and a cable are used to pivot the locking bar between a first position thereof wherein the locking bar and a portion of the stem may be inserted through aligned openings in the fitting and pipe and a second position.
    Type: Grant
    Filed: January 17, 1996
    Date of Patent: August 25, 1998
    Assignee: Central Plastics Company
    Inventor: Terry L. Stiles
  • Patent number: 5476562
    Abstract: Methods of producing electrically fusable sleeve connectors for connecting large diameter thermoplastic pipe sections and the sleeve connectors produced by such methods are provided. Methods of sealingly connecting adjacent ends of a pair of large diameter thermoplastic pipe sections by electric fusion are also provided. The methods of producing electrically fusable thermoplastic sleeve connectors broadly include the steps of winding a tape of molten thermoplastic material onto a large diameter core drum whereby adjacent windings are fused and upon being cooled a solid sleeve is formed, embedding an electric resistance heating wire in a surface of the sleeve while the thermoplastic material is still in the molten state and removing the sleeve after cooling with electric resistance heating wire embedded therein from the core drum.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: December 19, 1995
    Assignee: Central Plastics Company
    Inventor: James A. Inhofe, Jr.
  • Patent number: 5252157
    Abstract: Methods of producing electrically fusable sleeve connectors for connecting large diameter thermoplastic pipe sections and the sleeve connectors produced by such methods are provided. Methods of sealingly connecting adjacent ends of a pair of large diameter thermoplastic pipe sections by electric fusion are also provided. The methods of producing electrically fusable thermoplastic sleeve connectors broadly include the steps of winding a tape of molten thermoplastic material onto a large diameter core drum whereby adjacent windings are fused and upon being cooled a solid sleeve is formed, embedding an electric resistance heating wire in a surface of the sleeve while the thermoplastic material is still in the molten state and removing the sleeve after cooling with electric resistance heating wire embedded therein from the core drum.
    Type: Grant
    Filed: January 14, 1993
    Date of Patent: October 12, 1993
    Assignee: Central Plastics Company
    Inventor: James A. Inhofe, Jr.
  • Patent number: 4978837
    Abstract: An improved method and apparatus for electrically heat welding a thermoplastic fitting having an electric resistance heating element disposed therein. A controlled quantity of electric power is supplied to the heating element during the welding process to insure the making of a high quality weld. After the size of heating element and fitting are determined, a substantially constant voltage level electric power is supplied to the heating element of the fitting. When it is determined that the welding process is proceeding abnormally, the supply of electric power is terminated unless the abnormality is that the current level is too high. In that case, instead of terminating the welding process, the voltage of the electric power is reduced to that which results in current levels substantially equal to predetermined current levels for the size of heating element and fitting being welded which often results in a good weld being obtained even where the heating element is partially shorted out.
    Type: Grant
    Filed: April 13, 1990
    Date of Patent: December 18, 1990
    Assignee: Central Plastics Company
    Inventor: Dean E. Eggleston
  • Patent number: 4894521
    Abstract: An electric heating element for electrically fusing thermoplastic materials. The heating element comprises an elongated thermoplastic insulated wire wound in a spiral configuration with adjacent surfaces of the thermoplastic insulation adhered together.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: January 16, 1990
    Assignee: Central Plastics Company
    Inventor: Harold J. Evans
  • Patent number: 4801159
    Abstract: An improved gas meter riser assembly that is constructed in a manner that allows all welding to be carried out prior to application of protective coating thereby to maintain uniform epoxy cover. The invention consists of an outer riser pipe having a nipple welded thereon, which nipple is swaged to define a lower neck for insertion within the riser pipe. After welding and coating the nipple/pipe riser casing, an interior plastic pipe having an adaptor insert is fed downward through riser pipe until the adaptor insert is sealingly force-fit down within the swaged lower neck of the nipple. Selected spacers are provided between the plastic pipe and the pipe riser, and the lower end of the pipe riser may be suitably capped through a protective moisture seal.
    Type: Grant
    Filed: September 10, 1987
    Date of Patent: January 31, 1989
    Assignee: Central Plastics Company
    Inventor: Bobby W. Sehorn
  • Patent number: 4713129
    Abstract: A device and method for covering pilings of piers and the like includes a plastic cover or sheet which is wrapped around the piling for protecting the piling against rot, weather and wear. The plastic sheet ends overlap as they wrap around the pile. The ends are sealed and secured by a heatable strip extending between the overlapped ends of the sheet and which forms a fused plastic seam between the overlapped ends as the sheet is held tightly about the pile. A strap and a bar which presses over the heatable strip is provided for temporarily cinching the plastic sheet tightly about the pile and holding it while the heat fusing occurs.
    Type: Grant
    Filed: August 19, 1983
    Date of Patent: December 15, 1987
    Assignee: Central Plastics Company
    Inventors: James A. Inhofe, Jr., Harold J. Evans
  • Patent number: 4708527
    Abstract: A device and method of covering piles and the like includes a plastic cover or sheet which is wrapped around the pile for protecting the pile against rot, weather and wear. The plastic sheet ends overlap as they wrap around the pile. The ends are sealed and secured by a heating element extending between the overlapped ends of the sheet and which forms a fused plastic seam between the overlapped ends as the sheet is held tightly about the pile. A strap and bar which presses over the heating element are provided for temporarily cinching the plastic sheet tightly about the pile and holding it while the heat fusing occurs.
    Type: Grant
    Filed: March 4, 1987
    Date of Patent: November 24, 1987
    Assignee: Central Plastics Company
    Inventors: James A. Inhofe, Jr., Harold J. Evans
  • Patent number: 4684789
    Abstract: A method and apparatus for electrically heat welding a thermoplastic fitting having an electric resistance heating element disposed therein whereby a regulated quantity of electric power is supplied to the heating element during the welding process and the making of a high quality weld is insured. In accordance with the method, electric power is supplied to the resistance heating element of the fitting. The impedance and optionally, the resistance of the heating element are measured using low voltage electric power and the size of the fitting to be welded is determined therefrom. The initial magnitude of the current flowing through the heating element is sensed and compared with predetermined current levels for the size of fitting to be welded at various temperatures whereby the total time the controlled electric power should be supplied to the heating element of the fitting for the making of a high quality weld is determined.
    Type: Grant
    Filed: April 17, 1986
    Date of Patent: August 4, 1987
    Assignee: Central Plastics Company
    Inventor: Dean E. Eggleston
  • Patent number: 4663794
    Abstract: A plastic pipe scraper for scraping selected portions of the exterior surfaces of plastic pipe sections is provided. The apparatus is comprised of a frame member having a handle attached thereto adapted to fit over the plastic pipe sections, a scraper blade carrying member pivotally attached to one end of the frame member, a scraper blade attached to the blade carrying member and adjustable spring means attached to the frame member and to the blade carrying member for urging the scraper blade with selected force into contact with the external surfaces of the pipe sections.
    Type: Grant
    Filed: June 25, 1985
    Date of Patent: May 12, 1987
    Assignee: Central Plastics Company
    Inventor: Harold J. Evans
  • Patent number: 4642155
    Abstract: A method and apparatus for electrically heat welding a thermoplastic fitting having an electric resistance heating element disposed therein whereby a regulated quantity of electric power is supplied to the heating element during the welding process and the making of a high quality weld is insured. In accordance with the method, a controlled electric power is supplied to the resistance heating element of the fitting. The initial magnitude of the current flowing through the heating element is sensed and compared with predetermined current levels for various sizes of fittings whereby the size of the fitting as well as the total time the controlled electric power should be supplied to the heating element of the fitting for the making of a high quality weld are determined.
    Type: Grant
    Filed: January 29, 1986
    Date of Patent: February 10, 1987
    Assignee: Central Plastics Company
    Inventor: Russel G. Ramsey
  • Patent number: 4631107
    Abstract: A method and apparatus for electrically heat welding a thermoplastic fitting having an electric resistance heating element disposed therein whereby a regulated quantity of electric power is supplied to the heating element during the welding process and the making of a high quality weld is insured. In accordance with the method, a controlled electric power is supplied to the resistance heating element of the fitting. The initial magnitude of the current flowing through the heating element is sensed and compared with predetermined current levels for various sizes of fittings whereby the size of the fitting as well as the total time the controlled electric power should be supplied to the heating element of the fitting for the making of a high quality weld are determined.
    Type: Grant
    Filed: January 21, 1986
    Date of Patent: December 23, 1986
    Assignee: Central Plastics Company
    Inventor: Russel G. Ramsey
  • Patent number: 4602148
    Abstract: A method and apparatus for electrically heat welding a thermoplastic fitting having an electric resistance heating element disposed therein whereby a regulated quantity of electric power is supplied to the heating element during the welding process and the making of a high quality weld is insured. In accordance with the method, a controlled electric power is supplied to the resistance heating element of the fitting. The initial magnitude of the current flowing through the heating element is sensed and compared with predetermined current levels for various sizes of fittings whereby the size of the fitting as well as the total time the controlled electric power should be supplied to the heating element of the fitting for the making of a high quality weld are determined.
    Type: Grant
    Filed: May 16, 1985
    Date of Patent: July 22, 1986
    Assignee: Central Plastics Company
    Inventor: Russel G. Ramsey
  • Patent number: 4343518
    Abstract: A rod guide apparatus for a reciprocating rod comprised of two substantially identical half sections which include semicircular recesses therein and which are adapted to be lockingly clamped together adjacent opposite sides of the outer periphery of the rod whereby the rod extends through a bore formed by the semicircular recesses in the half sections. By the present invention each of the half sections includes at least one longitudinally extending ridge on a surface thereof within said semicircular recess whereby when the half sections are clamped together adjacent opposite sides of the rod, the ridges are positioned on opposite sides of the rod and deform the bore formed by the recesses through which the rod passes into a cross section of elliptical shape so that the clamped together half sections contact the periphery of the rod at at least four points thereby preventing slippage of apparatus on the rod.
    Type: Grant
    Filed: September 26, 1980
    Date of Patent: August 10, 1982
    Assignee: Central Plastics Company
    Inventor: Melvin E. Pourchot