Patents by Inventor David Grant Lingnau

David Grant Lingnau has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10926350
    Abstract: The present invention relates to an improved process and embodiments for girth welding of metal tubes and pipes and other shapes based on existing high speed, one-shot welding processes which have been modified to integrate a rapid heat treatment instantly after the weld is completed, while the weld is still hot and above specified transformation temperatures. The principle advantages are improved mechanical properties in the weld with a reduced cycle time to achieve them versus conventional separate post weld heat treatments such as tempering or quenching and tempering.
    Type: Grant
    Filed: July 27, 2018
    Date of Patent: February 23, 2021
    Assignee: Spinduction Weld, Inc.
    Inventor: David Grant Lingnau
  • Publication number: 20190030638
    Abstract: The present invention relates to an improved process and embodiments for girth welding of metal tubes and pipes and other shapes based on existing high speed, one-shot welding processes which have been modified to integrate a rapid heat treatment instantly after the weld is completed, while the weld is still hot and above specified transformation temperatures. The principle advantages are improved mechanical properties in the weld with a reduced cycle time to achieve them versus conventional separate post weld heat treatments such as tempering or quenching and tempering.
    Type: Application
    Filed: July 27, 2018
    Publication date: January 31, 2019
    Inventor: David Grant Lingnau
  • Publication number: 20180209565
    Abstract: A method for solid-state, one-shot, butt-welding of multiple coaxial metal pipe subassemblies that have a prescribed annular clearance to allow them to be welded separately yet simultaneously is described. The nested pipes or tubes making up of these subassemblies can thus be joined end to end to form pipelines or wells for oil, gas and geothermal and the like with specific desired advantages over conventional single-wall pipelines or wells casings. The advantages include an ability to monitor the condition of all or selected portions of the pressure envelope constituted by the pipeline or well casing and thereby identify damage with ample advance warning before failure and leakage or major spills occur.
    Type: Application
    Filed: December 29, 2017
    Publication date: July 26, 2018
    Applicant: Spinduction Weld, Inc.
    Inventor: David Grant Lingnau
  • Patent number: 5660753
    Abstract: An apparatus for heating a metal surface to remove a nonferrous thermosetting resin coating bonded to the metal surface. The apparatus uses a power supply device for providing an approximately 75-100 kW signal at approximately 10-40 kHz to the apparatus. A coil assembly device is coupled to the power supply device for producing a high frequency inductive field which will penetrate through the nonferrous thermosetting resin coating with virtually no attenuation and will induce an eddy current of sufficient power in the underlying metal substrate to rapidly heat the interface to a sufficient temperature to immediately destroy the interface bond between the nonferrous thermosetting coating and the metal substrate.
    Type: Grant
    Filed: June 16, 1995
    Date of Patent: August 26, 1997
    Inventor: David Grant Lingnau