Patents Assigned to IMI Engineering, Co.
  • Patent number: 4885893
    Abstract: A well mast apparatus is disclosed in the form of multiple, separately connectable sections including a lower mast section, an upper mast section and, if desired, several subsequent intermediate mast sections. The mast sections are provided with lifting rings positioned thereon for balancing the mast sections upon lifting. The upper mast section includes a connector offset from its lifting ring for controlling and guiding pivotal movement of the upper mast section relative to the lower mast section as the well mast is being raised. The lifting ring offset from the pivotable connector, which is interengaged between the fixed vertical lower section and the balanced horizontal second mast section, guides the direction and speed of rotation of the second mast section relative to the lower mast section during installation.
    Type: Grant
    Filed: September 10, 1987
    Date of Patent: December 12, 1989
    Assignee: IMI Engineering, Co.
    Inventors: Philip W. Wasterval, Jr., James E. Armstrong