Patents by Inventor Wilmer W. Crist

Wilmer W. Crist 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: 4709760
    Abstract: A method and apparatus for cementing an oil or gas well casing including a tubular body section for placing in an oil or gas well casing, the tubular body section being connectable at its upper end to a string of drill pipe and at its lower end to a perforating gun, the tubular body section having a hollow interior, a plurality of upper ports, and a plurality of lower ports, a sliding sleeve located inside the tubular body section adapted to permit drilling fluids to be pumped therethrough and out of the lower ports and to slide downwardly in response to pressure applied to the interior of the string of drill pipe when a seal is placed in contact with the sliding sleeve and thereby activate the perforating gun to perforate the casing, close the lower ports, and open the upper ports to permit cement or other fluids to be pumped outwardly through the upper ports.
    Type: Grant
    Filed: October 23, 1981
    Date of Patent: December 1, 1987
    Inventors: Wilmer W. Crist, Dan Firmin
  • Patent number: 4467864
    Abstract: An apparatus for distributing the weight of a workover or maintenance apparatus connected to a Christmas tree over the surface of the portion of the Christmas tree to which the workover apparatus is attached, including a plate which rests upon the portion of the Christmas tree to which the workover apparatus is attached, and a rigid support extending upwardly from the plate, the rigid support being connectable to said workover apparatus. The apparatus may include plugs for plugging the other strings of tubing contained in the Christmas tree to which the workover apparatus is not attached, and devices for adjusting the length of the rigid support.
    Type: Grant
    Filed: May 7, 1982
    Date of Patent: August 28, 1984
    Inventor: Wilmer W. Crist