US 5,386,746 AGranted

Apparatus for making and breaking joints in drill pipe strings

AssigneeHawk Industries, Inc.

InventorThomas D. Hauk

Life of this patent

Estimating the term…

Abstract

Apparatus for making and breaking joints in drill pipe strings has three jaws each of which is adjustable to an infinite number of settings. The jaw-adjustment means are symmetrical about a central plane, and incorporate a spherical section. Different portions of the spherical section operate relative to closing and self-energizing of each jaw, the particular operative portion depending upon the exact set or adjusted position of the jaw. Each jaw is constructed for stable clamping of a drill type portion, with only one side of each jaw having a die element that is rotatably mounted. The jaw-adjustment mechanism effects both opening and closing of the jaw, there being no necessity to manually pull on a jaw portion at any time.

Claims11

Dependent claims

A power jaw apparatus for applying high torques to sections of threadedly connected pipe, which comprises:

(a) at least one set of jaws adapted to apply torque in only a single direction to a section of threaded pipe,
said jaw set having a head element through which is provided an opening, said jaw set also having a hook element,
said hook element having a shank extending through said opening in said head element, said hook element also having a hook end connected to said shank on one side of said head element, said hook end and said head element defining between them a gap adapted to receive a pipe section, said hook end and said head element being adapted to grip a pipe section when it is in said gap,
(b) adjustable means to pivotally associate said hook element with said head element for pivotal movement of said hook element relative to said head element about a predetermined axis, said adjustable means also effecting movement of said shank through said opening to thereby increase and decrease the size of said gap whereby to adapt the power jaw apparatus for torquing of different diameters of pipe sections,
said adjustable means comprising a nut and further comprising thread means to rotatably and threadedly mount said nut on said shank on the other side of said head element,
a portion of the exterior of said nut being a surface of revolution about the axis of said nut,
said adjustable means further comprising first bearing means such that rotation of said nut relative to said shank effects movement of said shank through said opening,
said adjustable means further comprising second bearing means provided on said head and operatively associated with said surface of revolution, in such manner as to effect said pivotal movement of said hook element relative to said head element about said predetermined axis, and
(c) power means to exert a large force on said head to thereby rotate said head about a pipe section that is gripped in said gap for high-torque torquing of said pipe section about the axis of said pipe section, and for energization of said hook end and said head to achieve tighter gripping of said pipe section in said gap.

6 more elements

Dependencies are inferred from the claim text.

patentgrep

Loading patent…

Abstract

A power jaw apparatus for applying high torques to sections of threadedly connected pipe, which comprises:

(a) at least one set of jaws adapted to apply torque in only a single direction to a section of threaded pipe,
said jaw set having a head element through which is provided an opening, said jaw set also having a hook element,
said hook element having a shank extending through said opening in said head element, said hook element also having a hook end connected to said shank on one side of said head element, said hook end and said head element defining between them a gap adapted to receive a pipe section, said hook end and said head element being adapted to grip a pipe section when it is in said gap,
(b) adjustable means to pivotally associate said hook element with said head element for pivotal movement of said hook element relative to said head element about a predetermined axis, said adjustable means also effecting movement of said shank through said opening to thereby increase and decrease the size of said gap whereby to adapt the power jaw apparatus for torquing of different diameters of pipe sections,
said adjustable means comprising a nut and further comprising thread means to rotatably and threadedly mount said nut on said shank on the other side of said head element,
a portion of the exterior of said nut being a surface of revolution about the axis of said nut,
said adjustable means further comprising first bearing means such that rotation of said nut relative to said shank effects movement of said shank through said opening,
said adjustable means further comprising second bearing means provided on said head and operatively associated with said surface of revolution, in such manner as to effect said pivotal movement of said hook element relative to said head element about said predetermined axis, and
(c) power means to exert a large force on said head to thereby rotate said head about a pipe section that is gripped in said gap for high-torque torquing of said pipe section about the axis of said pipe section, and for energization of said hook end and said head to achieve tighter gripping of said pipe section in said gap.

6 more elements