An improved oil well drilling rig structure (10) is provided. The drilling rig structure (10) includes a base (32) for placement on the ground at a well site. The base (32) includes first and second ends (32a, 32b). A drill floor (14) supported on a floor box (12) having first and second ends (12a, 12b) is disposed parallel to and adjacent the first end (32a) of the base (32). The floor box (12) is coupled to the base (32) by spaced apart parallel legs (76, 78) each pivotally attached between the upper box (12) and the base (32) for elevating the floor (14) from a low position adjacent to the first end (32a) of the base (32) to an elevated position medially between the ends (32a, 32b) of the base (32) and located above the base (32) by rotation of the legs (76, 78) towards a vertical position. The structure (10) further includes a tensile link (40) having first and second ends (40a, 40b). The first end (40a) of the tensile link (40) is coupled adjacent the second end (12b) of the floor box (12) opposite the first end (32a) of the base (32). A thrust link (42) is provided having first and second ends (42a, 42b). The first end (42a) of the thrust link (42) is coupled adjacent to the second end (40b) of the tensile link (40). The second end (42b) of the thrust link (42) is pivotally coupled adjacent the second end (32b) of the base (32). Power driving structure (60) is connected to the base (32) and the links (40, 42) for drawing the second end (40a) of the tensile link (40) to a pin linkage position on the base (32) adjacent the second end (32b) of the base (32) as the legs (76, 78) approach the vertical position.
A cantilevered mast drilling rig is disclosed in which the erection operation for elevating the cantilevered mast and the drill rig floor to the elevated operating positions is a single step procedure. Both the cantilevered mast and the drill rig floor are completed on the ground prior to the elevating operation. The drill rig floor is pinned to the cantilevered mast so that, in response to actuation of the drawworks, the mast and drill rig floor are elevated to their operating positions as a single unit in a single operation.
The present invention is directed to a drilling rig base and a lower mast section that are collapsible into a compact transportable position. The base is expandable in the field to support a drilling platform and all necessary equipment, and the telescoping mast is also expanable for supporting the crown block and cables of the drawworks. More specifically, the rig of the present invention has a base having a plurality of beams, the outer beams being collapsible to a transportable position for placing on a single truck or trailer, and the A-frame lower mast section which is collapsible to a transportable position for placing on a single truck or trailer.
A field adjustable block for use with a bridge crane having a rotating cylindrical drum for rope. The block includes a cylindrical center pin having a key way recess parallel to an axis of the center pin. An inner side plate has an opening therethrough and an extending key receivable in the key way recess to prevent rotation of the inner side plate. Multiple sheaves are receivable over the center pin. At least one toroidal spacer is receivable over the center pin. A lock washer has an inwardly extending key receivable in the key way recess of the center pin and has a plurality of radially extending tabs. A nut has at least one notch to receive one of the extending tabs therein. An outer side plate is removably attached to the inner side plate by fasteners.
A method of self-aligning connections for a two section mast. The method includes the steps of transporting the elongated bottom mast section to a guide frame adjacent to a well site, the bottom mast section having a pair of front legs and a pair of rear legs. An elongated top mast section is transported to the well site, the top mast section having a pair of front legs and a pair of rear legs. The legs of the bottom mast section are positioned slightly below a level of the legs of the top mast section. Thereafter, the bottom mast section is raised slightly to order to engage the top mast section while simultaneously aligning the mast sections together. The sections are thereafter pinned together.
An embodied mobile drilling rig is made of three sections, two substructures and a mast section, which are easily transported and installed at a drilling site. Each substructure includes a mast starting section; a floor side box connected to the mast starting section; a subbase side box; elevating legs connected to the floor side box and the subbase side box; and a raising cylinder. The mast section connects to the mast starting sections. The raising cylinders engage the mast in order to raise the mast into a vertical orientation and then raise the floor side boxes into an operating position. The embodied mobile drilling rigs are configurable to be transported by road with as little as three major loads, all within legal or permitable load and dimensional limits for most regions.
