Cryogenic reciprocating pump intermediate distance piece

• US 8,915,719 B2
• Filed: 11/11/2011
• Issued: 12/23/2014
• Est. Priority Date: 11/11/2011
• Status: Active Grant

• Current Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Original Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Inventors: Street, John Charles
• Primary Examiner(s): FREAY, CHARLES GRANT
• Application Number:
  US13/294,717
• Publication Number:
  US 20130118424A1
• Time in Patent Office: 1,138 Days
• Field of Search: 417/53, 417/273, 417/364, 417/373, 62/6, 62/511, 624/74, 921/44, 921/68, 123/41.34
• US Class Current: 417/53
• CPC Class Codes: F04B 15/08 the liquids having low boiling points
• CPC Class Codes: F04B 19/06 Pumps for delivery of both liquid and elastic fluids at the same time wet gas pumps F04B37/20
• CPC Class Codes: F04B 53/02 Packing the free space between cylinders and pistons
• CPC Class Codes: F04B 53/08 Cooling; Heating; Preventing freezing

Abstract

The present invention teaches providing heating elements into the nose of an intermediate distance piece of a cryogenic reciprocating pump in order to warm the piston packing seals of the pump. The heating elements increase the temperature of the piston packing seals to limit deformation of the seals while the pump is in operation. In addition, a warm, dry vapor purge may be provided to the interior of the intermediate distance piece to reduce or eliminate rime from interfering with the piston packing seals.

Claims

1. A reciprocating pump assembly for pumping a cryogenic fluid, the assembly comprising:

a warm end having a crankshaft and a crosshead;

at least one cold end, each cold end having a piston, a pumping chamber, a suction port, a vent port and a discharge port;

at least one coupling, each coupling connecting the warm end to one of the at least one cold end; and

at least one intermediate distance piece, each of the at least one intermediate distance piece being connected to the warm end and to one of the at least one cold end, overlapping a portion of the one of the at least one cold end, and having at least one heating element at least partially contained therein, the at least one heating element being operatively disposed to allow for the circulation of a fluid through the at least one heating element.

2. The reciprocating pump assembly of claim 1, wherein each of the at least one cold end further comprises at least one piston packing seal, and wherein each of the at least one heating element is located at a first longitudinal position which at least partially overlaps with a second longitudinal position of the at least one piston packing seal, the first and second longitudinal positions being located along a longitudinal axis of the at least one cold end.

3. The reciprocating pump assembly of claim 2, wherein the at least one heating element comprises a first heating element and a second heating element and wherein at least a portion of the at least one piston packing seal is located between the first heating element and the second heating element.

4. The reciprocating pump assembly of claim 1, wherein each of the at least one intermediate distance piece further comprises at least one window formed therein to enable access to one of the at least one coupling from outside the at least one intermediate distance piece and a cover for each of the at least one window.

5. The reciprocating pump assembly of claim 1, further comprising an internal combustion engine having a cooling system, wherein the fluid is a coolant that is circulated through the cooling system of the internal combustion engine.

6. The reciprocating pump assembly of claim 5, wherein the internal combustion engine is operatively disposed to drive the crankshaft.

7. The reciprocating pump assembly of claim 1, further comprising a purge port located on each of the at least one intermediate distance piece, the purge port being connected to a supply of a cryogenic fluid, wherein each of the at least one intermediate distance piece defines an interior volume and the purge port is operatively disposed to inject the cryogenic fluid into the interior volume.

8. The reciprocating pump assembly of claim 5, further comprising:

a purge port located on each of the at least one intermediate distance piece, the purge port being in flow communication with a supply of a cryogenic fluid; and

a heat exchanger operatively disposed to heat the cryogenic fluid against the coolant;

wherein each of the at least one intermediate distance piece defines an interior volume and the purge port is operatively disposed to inject the cryogenic fluid into the interior volume.

9. A method comprising:

(a) pumping a first cryogenic fluid using a reciprocating pump assembly comprising a warm end having a crankshaft and a crosshead, at least one cold end, each cold end having a piston, a pumping chamber, a suction port, a vent port and a discharge port, at least one coupling that connects the warm end to one of the at least one cold end, at least one intermediate distance piece, each of the at least one intermediate distance piece being connected to the warm end, to one of the at least one cold end, and overlapping a portion of the warm end and a portion of the cold end; and

(b) during at least a portion of the performance of step (a), circulating a fluid through at least one heating element located in each of the at least one intermediate distance piece.

10. The method of claim 9, wherein step (b) comprises circulating a fluid, having a temperature above ambient temperature, through at least one heating element located in each of the at least one intermediate distance piece.

11. The method of claim 9, further comprising:

(c) covering any windows located on each of the at least one intermediate distance piece while step (a) is being performed.

12. The method of claim 9, further comprising:

(d) circulating the fluid through a cooling system of an internal combustion engine.

13. The method of claim 12, further comprising:

(e) driving the crankshaft with the internal combustion engine.

14. The method of claim 9, further comprising:

(f) purging an internal volume defined by each of the at least one intermediate distance piece using a second cryogenic fluid.

15. The method of claim 12, further comprising:

(f) purging an internal volume defined by each of the at least one intermediate distance piece using a second cryogenic fluid; and

(g) warming the second cryogenic fluid against the coolant prior to using the second cryogenic fluid in step (f).

16. A system comprising:

a reciprocating pump assembly for pumping a cryogenic fluid, the assembly comprising;

a warm end having a crankshaft and a crosshead;

at least one cold end, each cold end having a piston, at least one piston packing seal, a pumping chamber, a suction port, a vent port, a discharge port and a longitudinal axis;

at least one coupling, each coupling connecting the warm end to one of the at least one cold end; and

at least one intermediate distance piece having at least one window formed therein to enable access to one of the at least one coupling from outside the at least one intermediate distance piece and a cover for each of the at least one window, each of the at least one intermediate distance piece being connected to the warm end and to one of the at least one cold end, overlapping a portion of the one of the at least one cold end, and having first and second heating elements at least partially contained therein at a longitudinal position which at least partially overlaps with a longitudinal position of the at least one piston packing seal; and

an internal combustion engine having a cooling system in flow communication with each of the at least one heating element to enable circulation of a coolant fluid through the cooling system of the internal combustion engine and each of the at least one heating element, the internal combustion engine being operatively disposed to drive the crankshaft.

17. The system of claim 16, further comprising a purge port located on each of the at least one intermediate distance piece, the purge port being connected to a supply of a cryogenic fluid, wherein each of the at least one intermediate distance piece defines an interior volume and the purge port is operatively disposed to inject the cryogenic fluid into the interior volume.

18. The system of claim 17, further comprising a heat exchanger operatively disposed to heat the cryogenic fluid against the coolant fluid.