Patents by Inventor L. D. Hall

L. D. Hall 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).

  • Publication number: 20100236787
    Abstract: An improvement to a prior art sand release apparatus and method uses a pair of telescoped tubular members. In the improved system and method, the telescoped members are prevented from completely telescoping by a J-hook latch. Also in the improved system and method, a wear resistant seal prevents leakage when the telescoped members are not extended.
    Type: Application
    Filed: March 17, 2009
    Publication date: September 23, 2010
    Inventor: L. D. Hall
  • Patent number: 5018581
    Abstract: An apparatus and method are disclosed which are utilized in oil wells incorporating a reciprocating pump. The improvement is for the situation where the typical sand release apparatus has failed to clear a sand lock. The disclosed apparatus is such that the rotation of the two telescoping sleeves relative to each other is restricted thereby allowing the tool string to be unthreaded at a reverse thread at the top of the sand release apparatus. In this way, the apparatus allows removal of the tool string above the location where the tool is locked through rotation in a direction opposite of that normally used to unthread tool strings.
    Type: Grant
    Filed: June 11, 1990
    Date of Patent: May 28, 1991
    Inventor: L. D. Hall
  • Patent number: 4103739
    Abstract: In oil wells which utilize a reciprocating pump installed in a tubing string, an apparatus is disclosed which has the preferred form of a pair of telescoped tubular members threaded into the pump just above the lower end where sanding locks the pump. The two are telescoped together and are pinned by a shear pin. When it is time to pull the pump, if there is undue resistance to its removal from the tubing string, the shear pin will shear, releasing the two for telescoping movement. The innermost sleeve has a protruding shoulder limiting its upward travel. When the telescoping movement occurs, a set of slots is exposed. The slots open to the interior, and sand accumulated around the tool under pressure of a column of liquid standing thereabove washes down through the slots and out of the way. If no sanding occurs, the shear pin is not sheared and the two telescoped members maintain their original position.
    Type: Grant
    Filed: September 3, 1976
    Date of Patent: August 1, 1978
    Inventor: L. D. Hall