초록

A dual cylinder positive displacement pump is used to move drill cuttings. The pump may include one or more of a self-sealing wear ring member/wear plate member interface, stainless steel pumping cylinders, and a hopper with an inclined surface.

대표청구항 ▼

This has been a description of the present invention and the preferred mode of practicing the invention, however, the invention itself should only be defined by the appended claims wherein we claim: 1. A method of moving drill cuttings, the method comprising placing drill cuttings in a hopper, said

This has been a description of the present invention and the preferred mode of practicing the invention, however, the invention itself should only be defined by the appended claims wherein we claim: 1. A method of moving drill cuttings, the method comprising placing drill cuttings in a hopper, said hopper including a swing tube member communicating between a discharge port and alternately with first and second pumping cylinders, the method comprising alternately reciprocating respective piston heads within said first and second cylinders in synchronization with movement and positioning of said swing tube member to repeatedly: (i) draw drill cuttings into said first cylinder while at the same time forcing drill cuttings from said second cylinder through said swing tube member to said discharge port, (ii) pause while said swing tube member is transitioned from alignment with an outlet from said second cylinder to alignment with an outlet from said first cylinder, (iii) subsequently draw drill cuttings into said second cylinder while at the same time forcing drill cuttings from said first cylinder through said swing tube member to said discharge port and (iv) pause while said swing tube member is transitioned from alignment with the outlet of said first cylinder to alignment with the outlet of said second cylinder, the method further comprising creating a pressure of at least 50 bar (735 psi) within the swing tube member during operations (i) and (iii), said pressure within said swing tube member dropping by at least 80% during operations (ii) and (iv). 2. The method of claim 1 further comprising periodically redirecting said drill cuttings through a feedback path downstream of said discharge port, the feedback path leading back into said hopper. 3. The method of claim 1 further comprising providing an interface between said swing tube member and a wear ring member that moves with said swing tube member and abuts against a stationary wear plate member against said hopper wall, the interface including an internal pressure gap formed between a moving end of the swing tube member and the wear ring member so that pressure within the swing tube member reaches the pressure gap and acts on a pressure surface of the wear ring member to push the wear ring member against the stationary wear plate member, thereby providing sufficient sealing between the wear ring member and wear plate member as the pressure within the swing tube member increases during steps (i) and (iii). 4. The method of claim 3 comprising the further step of providing a pressure ring within an annular gap formed in a downstream end face of the wear ring member and adjacent a swing tube bracket disposed about the swing tube member for effecting its movement, the pressure ring providing sufficient pressure to hold said wear ring member in abutment with said wear plate member while still permitting the wear ring member to slide relative to said wear plate member during steps (ii) and (iv). 5. The method of claim 1 comprising the further step of providing said first and second cylinders of a material of stainless steel such that an internal surface of each cylinder work hardens during pumping operations. 6. The method of claim 1 comprising the further step of directing drill cuttings within the hopper toward the outlets of said first and second cylinders. 7. The method of claim 6 wherein the drill cuttings are directed toward the cylinder outlets by an inclined plate positioned toward a bottom of the hopper. 8. The method of claim 1 wherein the method involves moving unprocessed drill cuttings from on an offshore drilling platform along a flow path to a containment area of a seagoing vessel. 9. The method of claim 1 wherein the method involves moving unprocessed drill cuttings on an offshore drilling platform into an on-platform processing system for the drill cuttings. 10. A pump for moving drill cuttings, the pump comprising: a hopper for receiving drill cuttings; a swing tube member positioned within the hopper and having an outlet end in flow communication with a discharge port of the hopper, an inlet end movable between first and second openings that communicate respectively with first and second pumping cylinders, the inlet end including a wear ring member disposed thereabout for movement with the inlet end, the wear ring member abutting a stationary wear plate member adjacent a wall of the hopper, the stationary wear plate member defining the first and second openings; wherein an internal pressure gap is formed between the inlet end of the swing tube member and the wear ring member so that pressure within the swing tube member reaches the pressure gap and acts on a pressure surface of the wear ring member to push the wear ring member against the stationary wear plate member. 11. The pump of claim 10 wherein an internal surface of the inlet end of the swing tube member is outwardly tapered, and the wear ring member includes an internal step aligned with the outwardly tapered surface to at least in part define the pressure gap. 12. The pump of claim 11 wherein an annular end face of the inlet end of the swing tube member abuts a corresponding annular face of the wear ring member to define an outer limit of the pressure gap. 13. The pump of claim 12 wherein the inlet end of the swing tube member is disposed within the wear ring member, an annular gap is formed between an outer surface of the inlet end and an inner side of the wear ring member, a sealing ring is disposed within the annular gap, and the annular gap is located near the pressure gap but outside a drill cuttings flow path defined by the wear ring member and swing tube member. 14. The pump of claim 13 wherein a pressure ring is located to urge the wear ring member against the stationary wear plate member even in the absence of high pressure in the pressure gap, so as to hold said wear ring member in abutment with the wear plate member while still permitting the wear ring member to slide relative to the wear plate member. 15. The pump of claim 14 wherein the pressure ring is located in an annular gap formed in an end face of the wear ring member and adjacent a bracket connected with the swing tube member to effect movement of the inlet end, the bracket disposed about the swing tube member. 16. The pump of claim 10 wherein the inlet end of the swing tube member is disposed within the wear ring member, a sealing ring is located to provide a seal between the wear ring member and the swing tube member, a pressure ring is located to push the wear ring member against the stationary wear plate member even in the absence of high pressure in the pressure gap, so as to hold said wear ring member in abutment with the wear plate member while still permitting the wear ring member to slide relative to the wear plate member, with both the sealing ring and the pressure ring located outside a drill cuttings flow path defined by the wear ring member and swing tube member. 17. The pump of claim 10 wherein at least an internal surface of the first and second pumping cylinders is a stainless steel material that work hardens during pumping operations. 18. The pump of claim 17 wherein each of the first and second pumping cylinders is a single-piece tubular member formed entirely of stainless steel. 19. The pump of claim 10 wherein the hopper includes an inclined plate positioned to direct drill cuttings within the hopper toward the first and second openings. 20. The pump of claim 19 wherein a front wall of the hopper includes the discharge port, the wall adjacent the stationary wear plate member is a rear wall of the hopper, and an upper end of the inclined plate is located against the front wall, and a lower end of the inclined plate is positioned against a bottom surface of the hopper causing drill cuttings that move downward along the inclined plate to be directed away from the front wall. 21. A pump for moving drill cuttings, the pump comprising: a hopper for receiving drill cuttings; a swing tube member positioned within the hopper and having an outlet end in flow communication with a discharge port of the hopper, an inlet end movable between first and second openings that communicate respectively with first and second pumping cylinders, the inlet end including a wear ring member disposed thereabout for movement with the inlet end, the wear ring member abutting a stationary wear plate member adjacent a wall of the hopper, the stationary wear plate member defining the first and second openings; and a bracket member comprising: a first surface that abuts a surface of the wear ring member that is opposite the wear plate member, and a second surface that abuts the swing tube member; wherein the inlet end of the swing tube member is disposed within the wear ring member, a sealing ring is located to provide a seal between the wear ring member and the swing tube member, and a pressure ring is located adjacent to and directly between the bracket member and the wear ring member to push the wear ring member against the stationary wear plate member so as to hold said wear ring member in abutment with the wear plate member while still permitting the wear ring member to slide relative to the wear plate member, and wherein both the sealing ring and the pressure ring are located outside a drill cuttings flow path defined by the wear ring member and swing tube member. 22. The pump of claim 21 wherein at least an internal surface of the first and second pumping cylinders is a stainless steel material that work hardens during pumping operations. 23. The pump of claim 22 wherein each of the first and second pumping cylinders is a single-piece tubular member formed entirely of stainless steel. 24. The pump of claim 21 wherein the hopper includes an inclined plate positioned to direct drill cuttings within the hopper toward the first and second openings. 25. A pump for moving drill cuttings, the pump comprising: a hopper for receiving drill cuttings, the hopper including a front wall with a discharge port and a rear wall with first and second cylinder ports; a first pumping cylinder in communication with the first cylinder port; a second pumping cylinder in communication with the second cylinder port; a swing tube member positioned within the hopper and having an outlet end in communication with the discharge port, an inlet end movable between first and second openings respectively associated with the first and second cylinder ports, the cylinder ports at respective heights lower than a height of the discharge port, wherein the hopper includes an inclined surface positioned with its upper end toward the front wall and its lower end toward the rear wall to direct drill cuttings in the hopper toward the first and second openings, wherein the inclined surface is formed by an inclined plate positioned within a lower portion of the hopper. 26. The pump of claim 25 wherein spaced apart side walls of the hopper extend from the front wall to the rear wall, curved regions are provided between the side walls and a bottom wall of the hopper, and the inclined plate is tapered toward one end to match the curved regions. 27. The pump of claim 26 wherein the inclined plate is welded to the hopper. 28. The pump of claim 25 wherein spaced apart side walls of the hopper extend from the front wall to the rear wall, an agitator assembly is provided within the hopper, the agitator assembly extending between the sidewalls to support an agitator within the hopper and above the swing tube member toward the inlet end of the swing tube member.