Patents by Inventor Johann B. Springer

Johann B. Springer 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: 5010955
    Abstract: A casing mill for milling pipe cemented in an oil well comprises a body with a plurality of fixed milling blades having a diameter corresponding to the outside diameter of the pipe to be milled, and a second plurality of movable blades movable between a retracted position smaller than the inside diameter of the pipe to be milled, and an extended diameter corresponding to the outside diameter of a pipe coupling between adjacent sections of pipe. Means are provided for selectively moving the blades between the retracted and extended positions in response to drilling fluid flow. A stabilizer keeps the casing mill centered in the pipe to be milled. In this way, one can mill both the pipe and coupling in the vicinity of a coupling and mill only pipe between the vicinities of adjacent couplings.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: April 30, 1991
    Assignee: Smith International, Inc.
    Inventor: Johann B. Springer
  • Patent number: 4710074
    Abstract: A casing mill is set forth having a cylindrical body with one end adapted to be attached to a drill string and at the other end pilot vanes to guide the mill with respect to the casing. A plurality of blades project outwardly from the body to present a cutting edge for milling of the casing upon rotation of the mill. Polygonal tungsten carbide cutting elements are secured across a forward surface of each blade in a tesselating fashion, each element tilted in the direction of rotation of between 10-20 degrees. To mount the elements, the blade forward surface may include an inclined stairstep arrangement or inclined slots. Each element is brazed or bonded by a suitable organic adhesive to the forward surface.
    Type: Grant
    Filed: December 4, 1985
    Date of Patent: December 1, 1987
    Assignee: Smith International, Inc.
    Inventor: Johann B. Springer