Patents by Inventor Karl N. Tunstall

Karl N. Tunstall 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: 4420042
    Abstract: A method of running and pulling a siphon tube from a well while the well is under complete pressure control in which the siphon tube is run through a special stack, cut off and suspended in the stack, the cut end is dressed in the stack and a pulling tube engages the siphon tube in the stack and the siphon is pulled.
    Type: Grant
    Filed: March 5, 1982
    Date of Patent: December 13, 1983
    Assignee: Otis Engineering Corporation
    Inventor: Karl N. Tunstall
  • Patent number: 4274432
    Abstract: A valve having a valve stem extending through a bonnet with packing therebetween and a back seat and back seat valve member cooperable to isolate the packing from pressure within the valve body wherein an auxiliary piston is provided to positively hold the back seat valve member on the back seat under the influence of pressure other than the pressure within the valve body. The back seat valve may be actuated by auxiliary pressure while changing the bonnet packing and may also serve to positively close the valve in the case of a malfunction of the usual closing mechanism.
    Type: Grant
    Filed: January 21, 1980
    Date of Patent: June 23, 1981
    Assignee: Otis Engineering Corporation
    Inventors: Karl N. Tunstall, M. L. Warren
  • Patent number: 4199131
    Abstract: A portable add-on actuator module for use with a wireline cutting surface safety valve to provide supplemental energy for closing and simultaneously cutting a wireline extending through the surface safety valve in the event of an emergency. The unit includes a spring loaded locking collet assembly arranged to engage a locking recess within the stem of a surface safety valve so that the spring force may be added to normal valve closing forces such as line pressure and valve stem springs to supplement such forces for insuring the cutting by the surface valve member of a wireline extending through the member. The actuator module has a body which rests on the safety valve body without the use of any connecting structure. The module also includes structure for hydraulically compressing the spring for connecting the module on a safety valve and for hydraulically shifting the latching collet assembly to a disengaging condition for releasing the module from a safety valve.
    Type: Grant
    Filed: September 23, 1977
    Date of Patent: April 22, 1980
    Assignee: Otis Engineering Corporation
    Inventors: Israel Boski, Karl N. Tunstall, M. L. Warren
  • Patent number: 4087073
    Abstract: Disclosed is a safety valve and hydraulic actuator for the safety valve. The safety valve includes a valve body and a valve member. The hydraulic actuator is adapted to be attached to the valve body and includes a cylinder and piston. A pilot valve controls the pressurizing of the cylinder to affect movement of the piston. This abstract is neither intended to define the scope of the invention, which, of course, is measured by the claims nor is it intended to be limiting in any way.
    Type: Grant
    Filed: April 26, 1976
    Date of Patent: May 2, 1978
    Assignee: Otis Engineering Corporation
    Inventors: James E. Runberg, Karl N. Tunstall