Sinker bar with centralizer

1 . A sinker bar, comprising:

a cylindrical body having an outer surface and opposing first and second ends, the outer surface exhibiting a first diameter;

one or more grooves defined in the outer surface between the first and second ends and thereby defining a grooved portion of the body, at least one of the one or more grooves exhibiting a second diameter smaller than the first diameter; and

a centralizer attached to the body at the grooved portion and encapsulating the one or more grooves, the centralizer providing opposing first and second centralizer ends extending axially beyond opposing axial ends of the grooved portion and terminating at the outer surface.

2 . The sinker bar of claim 1 , wherein each groove of the one or more grooves is defined circumferentially about the outer surface of the body.

3 . The sinker bar of claim 2 , wherein the one or more grooves comprise a plurality of grooves and each groove is axially offset and arranged parallel to each other.

4 . The sinker bar of claim 1 , wherein the centralizer provides an outer radial surface extending parallel to the outer surface of the body, and wherein each centralizer end provides a transition surface that transitions from the outer radial surface to the outer surface of the body.

5 . The sinker bar of claim 4 , wherein the transition surface is selected from the group consisting of straight, curved, arcuate, progressively varying, and any combination thereof.

6 . The sinker bar of claim 1 , wherein the one or more grooves includes an elongated groove extending parallel to a longitudinal axis of the body.

7 . The sinker bar of claim 1 , wherein the one or more grooves comprise at least one helical groove.

8 . The sinker bar of claim 1 , wherein the one or more grooves comprise two annular grooves axially spaced from each other and at least one helical groove extending between the two annular grooves.

9 . The sinker bar of claim 1 , wherein the centralizer includes:

a guide body;

a plurality of lobes extending radially outward from the guide body and defining an outer radial surface of the centralizer; and

a flute defined between angularly adjacent lobes of the plurality of lobes.

10 . The sinker bar of claim 1 , further comprising a surface prep region defined on the outer surface between the first and second ends and extending axially past the opposing axial ends of the grooved portion.

11 . The sinker bar of claim 10 , wherein the surface prep region is prepared by at least one of shot peening, knurling, sand blasting, chemical etching, and any combination thereof.

12 . A sinker bar, comprising:

a cylindrical body having an outer surface and opposing first and second ends;

one or more grooves defined in the outer surface between the first and second ends and thereby defining a grooved portion of the body; and

a centralizer attached to the body at the grooved portion and encapsulating the one or more grooves, the centralizer providing opposing first and second centralizer ends extending axially beyond opposing axial ends of the grooved portion,

wherein the one or more grooves includes an elongated groove extending parallel to a longitudinal axis of the body, and

wherein a length of the elongated groove is larger than a width of the elongated groove.

13 . A sinker bar, comprising:

a cylindrical body having an outer surface and opposing first and second ends;

one or more grooves defined in the outer surface between the first and second ends and thereby defining a grooved portion of the body; and

a centralizer attached to the body at the grooved portion and encapsulating the one or more grooves, the centralizer providing opposing first and second centralizer ends extending axially beyond opposing axial ends of the grooved portion,

wherein the one or more grooves each exhibit a hemispherical cross-section.

14 . The sinker bar of claim 13 , wherein the one or more grooves are angularly offset from each other about the circumference of the body.

15 . A well system, comprising:

a pumping unit;

a wellhead arranged adjacent the pumping unit and above a wellbore;

a rod string operatively coupled to the pumping unit and extending through the wellhead into the wellbore, the rod string including a plurality of sucker rods, a submersible pump arranged at a distal end of the plurality of sucker rods, and a sinker bar interposing the plurality of sucker rods and the submersible pump, the sinker bar including:

a cylindrical body having an outer surface and opposing first and second ends the outer surface exhibiting a first diameter;

one or more grooves defined in the outer surface between the first and second ends and thereby defining a grooved portion of the body, at least one of the one or more grooves exhibiting a second diameter smaller than the first diameter; and

a centralizer attached to the body at the grooved portion and encapsulating the one or more grooves, the centralizer providing opposing first and second centralizer ends extending axially beyond opposing axial ends of the grooved portion and terminating at the outer surface.

16 . The well system of claim 15 , wherein each groove of the one or more grooves is defined circumferentially about the outer surface of the body.

17 . The well system of claim 15 , wherein the centralizer provides an outer radial surface extending parallel to the outer surface of the body, and wherein each centralizer end provides a transition surface that transitions from the outer radial surface to the outer surface of the body.

18 . The well system of claim 15 , wherein the one or more grooves includes an elongated groove extending parallel to a longitudinal axis of the body.

19 . The well system of claim 15 , wherein the one or more grooves comprise at least one helical groove.

20 . The well system of claim 15 , wherein the centralizer includes:

a guide body;

a plurality of lobes extending radially outward from the guide body and defining an outer radial surface of the centralizer; and

a flute defined between angularly adjacent lobes of the plurality of lobes.