Connecting rod and crosshead assembly for enhancing the performance of a reciprocating pump

Patent metadata

Field	Value
Publication number	US-2016369792-A1
Application number	US-201615185143-A
Country	US
Kind code	A1
Filing date	Jun 17, 2016
Priority date	Jun 18, 2015
Publication date	Dec 22, 2016
Grant date	—

Abstract

A method and apparatus for a reciprocating pump assembly, including a crosshead and a connecting rod. The crosshead includes a main body having a cylindrical bore formed therethrough and defining a bearing surface, and a window formed through the main body and into the cylindrical bore. The connecting rod includes a small end disposed within the cylindrical bore and a beam portion extending through the window and being connected to the small end. In an exemplary embodiment, a bearing including a tubular body and a cutout is disposed within the cylindrical bore. In another exemplary embodiment, a clamp engages both the main body of the crosshead and the respective opposing end portions of the small end, thus reducing axial displacement of the small end relative to the crosshead.

First claim

What is claimed is:

1 . An apparatus for a reciprocating pump assembly, the apparatus comprising:
a crosshead comprising: a main body; a cylindrical bore formed through, and at least partially defining a bearing surface in, the main body, the bearing surface extending about a first axis; and a window formed in the main body transversely to the first axis; and a connecting rod comprising a small end defining opposing end portions and adapted to extend within the cylindrical bore, the small end extending about a second axis, and a beam portion adapted to be connected to the small end, the beam portion and the small end being separately formed; wherein, when the small end extends within the cylindrical bore and the beam portion is connected to the small end, the first and second axes are substantially coaxial and the beam portion extends through the window.

2 . The apparatus of claim 1 , wherein the beam portion is adapted to be connected to the small end using one or more fasteners.

3 . The apparatus of claim 1 , wherein the crosshead further comprises a pair of struts integrally formed with the main body and partially defining the bearing surface, the struts being formed on opposing sides of the window.

4 . The apparatus of claim 1 , wherein, at the location of the window, the bearing surface of the crosshead extends more than 180 degrees, but less than 360 degrees, about the first axis.

5 . The apparatus of claim 1 , further comprising a bearing adapted to extend within the cylindrical bore, the bearing comprising a tubular body defining an interior passage and extending about a third axis, and a cutout formed in the tubular body transversely to the third axis, the cutout being adapted to be substantially aligned with the window so that the tubular body substantially covers the bearing surface; wherein, when the bearing and the small end extend within the cylindrical bore, the cutout is substantially aligned with the window, and the beam portion is connected to the small end: the beam portion extends through both the cutout and the window; the bearing is disposed radially between the bearing surface and the small end, thus providing lubrication and/or wear resistance therebetween; and the first, second, and third axes are substantially coaxial.

6 . The apparatus of claim 5 , wherein, at the location of the cutout, the tubular body of the bearing extends more than 180 degrees, but less than 360 degrees, about the third axis.

7 . The apparatus of claim 1 , further comprising a clamp, the clamp comprising a pair of plates adapted to engage both the main body of the crosshead and the respective opposing end portions of the small end, and a tensioner adapted to be connected to, and to apply tension between, the plates; wherein, when the plates engage both the main body of the crosshead and the opposing end portions of the small end, and the tensioner is connected to, and applies tension between, the plates, the clamp prevents, or at least reduces, axial displacement of the small end relative to the crosshead.

8 . A method of assembling a crosshead and a connecting rod for a reciprocating pump, the method comprising:
providing the crosshead, the crosshead comprising: a main body; a cylindrical bore formed through, and at least partially defining a bearing surface in, the main body, the bearing surface extending about a first axis; and a window formed in the main body transversely to the first axis; positioning a small end of the connecting rod within the cylindrical bore, the small end defining opposing end portions and extending about a second axis; and connecting a beam portion of the connecting rod to the small end, the beam portion and the small end being separately formed; wherein, when the small end is positioned within the cylindrical bore and the beam portion is connected to the small end, the first and second axes are substantially coaxial and the beam portion extends through the window.

9 . The method of claim 8 , wherein connecting the beam portion to the small end of the connecting rod comprising connecting the beam portion to the small end using one or more fasteners.

10 . The method of claim 8 , wherein the crosshead further comprises a pair of struts integrally formed with the main body and partially defining the bearing surface, the struts being formed on opposing sides of the window.

11 . The method of claim 8 , wherein, at the location of the window, the bearing surface of the crosshead extends more than 180 degrees, but less than 360 degrees, about the first axis.

12 . The method of claim 8 , further comprising positioning a bearing within the cylindrical bore so that: a tubular body of the bearing is engaged with the bearing surface of the crosshead, the tubular body defining an interior passage and extending about a third axis; and a cutout of the bearing is substantially aligned with the window of the crosshead, the cutout formed in the tubular body transversely to the third axis; wherein, when the bearing and the small end are positioned within the cylindrical bore and the beam portion is connected to the small end: the beam portion extends through both the cutout and the window; the bearing is disposed radially between the bearing surface and the small end, thus providing lubrication and/or wear resistance therebetween; and the first, second, and third axes are substantially coaxial.

13 . The method of claim 12 , wherein, at the location of the cutout, the tubular body of the bearing extends more than 180 degrees, but less than 360 degrees, about the third axis.

14 . The method of claim 8 , further comprising connecting a clamp to the crosshead and the connecting rod so that:
a pair of plates of the clamp are engaged with both the main body of the crosshead and the respective opposing end portions of the small end; and a tensioner of the clamp is connected to, and applies tension between, the plates so that the clamp prevents, or at least reduces, axial displacement of the small end relative to the crosshead.

15 . A reciprocating pump assembly, comprising:
a fluid end comprising a plunger bore and a plunger adapted to reciprocate within the plunger bore; a power end comprising a tubular guide member, a crank shaft adapted to rotate about a first axis, and a crank throw offset from the first axis and connected to the crankshaft; and a mechanical linkage operably coupling the power end to the fluid end, the mechanical linkage comprising:
a crosshead comprising: a main body; a cylindrical bore formed through, and at least partially defining a bearing surface in, the main body, the bearing surface extending about a first axis; and a window formed in the main body transversely to the first axis; and
a connecting rod comprising a small end defining opposing end portions and extending within the cylindrical bore, the small end extending about a second axis, and a beam portion connected to the small end, the beam portion and the small end being separately formed;
wherein the beam portion extends through the window and the first and second axes are substantially coaxial.

16 . The reciprocating pump assembly of claim 1 , wherein the beam portion is connected to the small end using one or more fasteners.

17 . The reciprocating pump assembly of claim 15 , wherein the connecting rod further comprises a big end connected to the beam portion and split along a plane into a seat portion and a cap portion, the seat and cap portions together defining a cylindrical inner surface that engages the crank throw, the seat portion being integrally

Assignees

• Spm Flow Control Inc

Inventors

• Wagner Bryan

Classifications

• F04B53/006

  Crankshafts · CPC title

• F04B53/22

  Arrangements for enabling ready assembly or disassembly · CPC title

• F04B9/045

  the means being eccentrics · CPC title

• F16C5/00

  Crossheads; Constructions of connecting-rod heads or piston-rod connections rigid with crossheads (piston-rods, i.e. rods rigidly connected to the piston, F16J7/00) · CPC title

• F04B53/16

  Casings; Cylinders; Cylinder liners or heads; Fluid connections · CPC title