US20200116143A1

US20200116143A1 - Compressor diaphragm piston rod seal

Info

Publication number: US20200116143A1
Application number: US16/598,384
Authority: US
Inventors: Travis Boerema
Original assignee: Corken Inc
Current assignee: Advanced Flow Solutions Inc
Priority date: 2018-10-11
Filing date: 2019-10-10
Publication date: 2020-04-16

Abstract

One or more techniques and systems are described herein for a compressor technology that may be used to improve operations and outcomes of a compressor. For example, existing compressors with reciprocating pistons utilize a packing system to mitigate leaks. As described herein, a flexible diaphragm may be disposed in a fixed arrangement with the piston rod and the chamber wall of a compressor to improve leakage prevention, and improve overall operations and maintenance of the compressor.

Description

This nonprovisional patent application claims priority to provisional patent application 62/744,183 filed on Oct. 11, 2018, the entirety of which is incorporated herein by reference.

BACKGROUND

Large industrial compressors are used in multiple applications among the world and across industries, including liquefied petroleum gas (LPG) loading/unloading, gas lift operations, gas (e.g., hydrogen) compression, and various other aspects of gas compression across the globe.

SUMMARY

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key factors or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
One or more techniques and systems are described herein for a compressor technology that may be used to improve operations and outcomes of a compressor. For example, existing compressors with reciprocating pistons utilize a packing system to mitigate leaks. As described herein, a flexible diaphragm may be disposed in a fixed arrangement with the piston rod and the chamber wall of a compressor, to improve leakage prevention, and improve overall operations and maintenance of the compressor.
A compressor may comprise a first chamber and a second chamber fluidly coupled with the first chamber. A piston may be disposed in the first chamber. A rod may be operably connected to the piston, and the rod may extend from the first chamber and through the second chamber. A diaphragm disposed in the second chamber operably connected to the piston and a sidewall of the second chamber.
To the accomplishment of the foregoing and related ends, the following description and annexed drawings set forth certain illustrative aspects and implementations. These are indicative of but a few of the various ways in which one or more aspects may be employed. Other aspects, advantages and novel features of the disclosure will become apparent from the following detailed description when considered in conjunction with the annexed drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a component diagram illustrating an example of an existing reciprocating compressor.

FIG. 2A is a component diagram illustrating one example of an implementation of one or more portions of one or more systems described herein.

FIG. 2B is a component diagram illustrating one example of an implementation of one or more portions of one or more systems described herein.

FIG. 2C is a component diagram illustrating one example of an implementation of one or more portions of one or more systems described herein.

FIG. 3A is a perspective view of an example of a compressor.

FIG. 3B is another perspective view of an example of a compressor.

FIG. 3C is a partial cross sectional view of an example of a compressor.

FIG. 4 is a component diagram illustrating one example of an implementation of one or more portions of one more systems described herein.

DETAILED DESCRIPTION

The claimed subject matter is now described with reference to the drawings, wherein like reference numerals are generally used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the claimed subject matter. It may be evident, however, that the claimed subject matter may be practiced without these specific details. In other instances, structures and devices are shown in block diagram form in order to facilitate describing the claimed subject matter.
Large industrial compressors are used in multiple applications across the world ranging from liquefied petroleum gas (LPG) loading/unloading, gas lift operations, hydrogen compression, and various other aspects of gas compression across the globe. Most compressors of this size and nature (e.g., 5-500+ Horse Power) utilize a packing scheme to: 1) mitigate oil carry over from the crankcase to the process gas; 2) mitigate process gas contamination in the compressor crankcase/mechanical chambers; and 3) mitigate process gas leakage into the operating environment (e.g., environmental leaks).
In most cases the existing packaging scheme is composed of either a series of v-ring lip type seals that are stacked together, or that are arranged in a segmented arrangement, depending on application needs. The inventive concept described herein was inspired by the current state of packing design across the compressor industry, and a need to improve compressor efficiencies, and to reduce adverse effects on the environment due to leakage of either process gas or oil.
The inventive concept described herein allows for a new packing design which separates both chambers from each other, and mitigates carry over potential of oil to process gas, while also reducing leak potential by providing a diaphragm. Such as design will not wear out as often due to piston stroke, but instead stays in motion with the piston rod.
The inventive concept described herein can incorporate a packing diaphragm created from a flexible elastomer material, which can be utilized as a seal between the compression chamber (e.g., comprising process gas) and the mechanical work chamber (e.g., crankcase, crosshead guide). As an example, the diaphragm may be made of materials that are appropriate for the target use, such as to accommodate specific products that may come into contact with the diaphragm. For example, the diaphragm may comprise Teflon, Viton, nitrile silicone, EPDM rubber (ethylene propylene diene monomer (M-class) rubber), or any other flexible and appropriate thermoplastic or rubber that could be used as a diaphragm.
As seen in FIG. 1, an existing standard packing cartridge in a compressor 100 incorporates a packing barrel 102 (e.g., or barrels), and possibly a wiper 104 to separate the two chambers via a wear component (e.g., a v-ring or segmented packing set), which is stationary and wears as the piston rod 106 moves up/down to compress the process gas. Typically, the pressure in the crankcase portion is 5 to 30 PSI; and leakage often occurs from the compression chamber.
As seen in FIGS. 2A, 2B, 2C, 3A, and 3B, utilizing the inventive concept described herein, a compressor 200 that may be in a vertical or horizontal position. The compressor 200 can comprise a first chamber or compression chamber 218. In one implementation, the compressor 200 may also comprise a second chamber fluidly coupled with the first chamber. The second chamber may be a mechanical work chamber 216. A reciprocating piston 220 may be disposed in the compression chamber 218. A piston rod 212 may be operably connected to the piston 220. The rod 212 may extend from the first chamber or compression chamber 218 and through the second chamber or mechanical work chamber 218. A diaphragm may be configured to fluidly separate the first chamber and the second chamber. The diaphragm 210 may have a process side and an environment side, wherein environment material on the environment side is prevented from entering the process side, and process material on the process side is prevented from entering the environment side. In another implementation, the diaphragm 210 may be disposed in the mechanical work chamber 216. In another implementation, the diaphragm may be disposed between the compression chamber 218 and the mechanical work chamber 216. The diaphragm 210 may comprise a single unitary piece. The diaphragm may be utilized as a flexible seal that can be installed and fixedly attached to the piston rod 212 and the chamber walls 214 between the mechanical work chamber 216 and the compressor chamber 218. With the diaphragm 210 being sealingly connected to the chamber walls 214, the compression chamber 218 and the mechanical work chamber 216 may be completely separated. Further, the diaphragm 210 may be a packing diaphragm. In one implementation, the diaphragm 210 may have a process side 222 and an environment side 224. The process side 222 encounters product entering and exiting the compression chamber 218. Process material may include product gas, such as, but not limited to liquid propane gas, gas lift, hydrogen, butane, or other process gas being acted upon by the piston 220. The environment side 224 of the diaphragm may encounter other aspects of the compressor and environment material such as, but not limited to lubricating fluid such as oil. As shown in FIGS. 2A-2C, the mechanical work chamber 216 is free of packing wear components, such as a packing 102 and wiper 104, but not limited thereto. With the diaphragm 210 separating the compression chamber 216 from the mechanical work chamber 218, the diaphragm is configured to prevent transfer of the undesired fluid on the environment side from entering the compression chamber 216, and rising contamination of the product being compressed in the compression chamber, for example, process gas.
In the example of FIG. 2A, the diaphragm 210 can move up with the compressor upstroke of the piston rod 212. In the upstroke position, the diaphragm may comprise a convex shape. In FIG. 2B the diaphragm 210 can move down with the compressor downstroke of the piston rod 212. In one implementation, the diaphragm may comprise a concave shape. Further, in FIG. 2C the diaphragm 210 can be centered (e.g., not flexed), and disposed at the midpoint of the compressor stroke of the piston rod 212.
As an example, as the compressor turns through one full rotation, one full compression cycle may be completed and the diaphragm 210 can move from bottom dead center to top dead center. This process can repeat with every rotation of the compressor crankshaft 230, which may be operably coupled to the piston rod 212. In other words, one rotation of the crank shaft 230 may comprise the diaphragm 210 comprising an upstroke position, a center position, a downstroke position, a center position and returning to the upstroke position.
In one nonlimiting example, the compressor 200 may further comprise a first stage inlet 232 fluidly coupled with a first stage outlet 234. The first stage inlet 232 and the first stage outlet 234 may be operably coupled with the mechanical work chamber 216 with valves such that product can enter and exit the compression chamber 218. The compressor may be further comprise a second stage inlet 238 and a second stage outlet 240. The second stage inlet 238 and the second stage outlet 234 may be positioned adjacent to or above the compression chamber 218. The second stage inlet may be fluidly coupled with the first stage outlet 234 and the second stage outlet 240. Valves fluidly coupled with the second stage inlet 238 and the second stage outlet 240 may further regulate product, such as process gas, being passed through the compressor 200. The compressor 200 may also comprise a crosshead 242 as shown in FIG. 3C, which may be disposed within the mechanical work chamber 216. The diaphragm 210 may be disposed between the crosshead 242 and the compression chamber 218.
In yet another implementation, two separate rods for two separate chambers both utilizing the diaphragm. In another nonlimiting implementation shown in FIG. 4, the compressor 200 may comprise a parallel configuration where the compressor may comprise a dual throw crankshaft and two separate piston/piston rod assemblies, both of which could use a diaphragm 210.
This inventive concept described herein could be used in practically any compression application where the purity of the process gas is very important, and contamination could potentially ruin the end product gas and/or components downstream from the compressor. Further, the inventive concept described herein would reduce any process gas leakage to the mechanical work chamber, and out to the operating environment. The inventive concept described herein is novel because it eliminates the typical packing wear component (e.g., FIG. 1), which deteriorates over time due to friction/heat between the piston rod and the packing material. For example, by utilizing a moving packing material (e.g., the flexible diaphragm) the heat created by friction between the two components can be mitigated, and the need to replace worn packing material is also mitigated.
This inventive concept described herein comprises and improvement over existing technology for at least the following reasons. Reduced maintenance intervals on the pumps are achieved because the wear component (e.g., packing v-rings or segments) of existing compressors will not need to be replaced often. Further, leakage reduction to the atmosphere and mechanical work chamber may occur due to improved sealing between the pump chambers 216, 218. Further, elimination of fluid, such as oil, carry over into process gas in the compression chamber 218 may occur due to improved sealing of the diaphragm 210. In addition, example implementations described herein may achieve better compliance with ever increasing emphasis on emission standards.
The word “exemplary” is used herein to mean serving as an example, instance or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete fashion. As used in this application, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.” That is, unless specified otherwise, or clear from context, “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then “X employs A or B” is satisfied under any of the foregoing instances. Further, At least one of A and B and/or the like generally means A or B or both A and B. In addition, the articles “a” and “an” as used in this application and the appended claims may generally be construed to mean “one or more” unless specified otherwise or clear from context to be directed to a singular form.
Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.
Also, although the disclosure has been shown and described with respect to one or more implementations, equivalent alterations and modifications will occur to others skilled in the art based upon a reading and understanding of this specification and the annexed drawings. The disclosure includes all such modifications and alterations and is limited only by the scope of the following claims. In particular regard to the various functions performed by the above described components (e.g., elements, resources, etc.), the terms used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations of the disclosure. In addition, while a particular feature of the disclosure may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms “includes,” “having,” “has,” “with,” or variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term “comprising.”
The implementations have been described, hereinabove. It will be apparent to those skilled in the art that the above methods and apparatuses may incorporate changes and modifications without departing from the general scope of this invention. It is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims or the equivalents thereof.

Claims

What is claimed is:

1. A compressor, comprising:

a first chamber;

a second chamber fluidly coupled with the first chamber;

a piston disposed in the first chamber;

a rod operably connected to the piston, the rod extending from the first chamber and through the second chamber;

a diaphragm configured to fluidly separate the first chamber and the second chamber, the diaphragm having a process side and an environment side, wherein environment material on the environment side is prevented from entering the process side, and process material on the process side is prevented from entering the environment side.

2. The compressor of claim 1, where the diaphragm is disposed in the second chamber operably connected to the piston and a sidewall of the second chamber.

3. The compressor of claim 1, the first chamber is a compression chamber.

4. The compressor of claim 1, wherein the second chamber is a mechanical work chamber.

5. The compressor of claim 1, the diaphragm comprising an elastomeric material.

6. The compressor of claim 1, the diaphragm comprising an upstroke position, a downstroke position, and a center position.

7. The compressor of claim 6, wherein the upstroke position comprises the diaphragm comprising a convex shape.

8. The compressor of claim 6, wherein the downstroke position comprises the diaphragm comprising concave shape.

9. The compressor of claim 6, wherein the center position comprises a diaphragm in a centered position.

10. The compressor of claim 1, wherein the environment material is oil.

11. The compressor of claim 1, further comprising a crank shaft operably coupled with the piston rod.

12. The compressor of claim 11, wherein the crank shaft comprises one rotation, one rotation comprising the diaphragm comprising an upstroke position, a downstroke position, and a center position.

13. The compressor of claim 1, further comprising:

a first stage inlet fluidly coupled with a first stage outlet fluidly coupled with the mechanical work chamber and the compression chamber;

a second stage inlet fluidly coupled with the first stage outlet and a second stage outlet; and

a crosshead; the diaphragm disposed between the crosshead and the compression chamber.

14. A compressor, comprising:

a compression chamber;

a mechanical work chamber fluidly coupled with the compression chamber;

a piston disposed in the compression chamber;

a rod operably connected to the piston, the rod extending from the compression chamber and through the mechanical work chamber;

a packing diaphragm configured to fluidly separate the first chamber and the second chamber, the diaphragm having a process side and an environment side, wherein environment material on the environment side is prevented from entering the process side, and process material on the process side is prevented from entering the environment side.

15. The compressor of claim 14, wherein the packing diaphragm is disposed in the mechanical work chamber sealingly connected to the piston and a sidewall of the mechanical work chamber, the mechanical work chamber free of packing wear components.

16. The compressor of claim 15, the packing diaphragm comprising an upstroke position, a downstroke position, and a center position.

17. The compressor of claim 14, the packing diaphragm comprising an upstroke position, a downstroke position, and a center position, the packing diaphragm comprising a convex shape relative to the compression chamber during the upstroke position, and the packing diaphragm comprising a concave shape during the downstroke position.

18. The compressor of claim 14, wherein the compressor is a vertical industrial compressor.

19. The compressor of claim 14, further comprising:

a crosshead disposed within the mechanical work chamber; and

a crankshaft operably connected to the crosshead;

the compression chamber comprising a process gas, the packing diaphragm disposed between the crosshead and the compression chamber and configured to prevent contamination and/or leakage from the crankcase to the process gas.

20. A compressor, comprising:

a compression chamber;

a mechanical work chamber fluidly coupled with the compression chamber, the mechanical work chamber having a process side and an environment side;

a piston disposed in the compression chamber;

a packing diaphragm disposed in the mechanical work chamber sealingly connected to the piston and a sidewall of the mechanical work chamber, the mechanical work chamber free of packing wear components.

a first stage inlet fluidly coupled with a first stage outlet fluidly coupled with the process side of the mechanical work chamber and the compression chamber;

the compression chamber comprising a product, the packing diaphragm configured to prevent contamination and/or leakage from the environment side of the packing diaphragm to the process gas in the compression chamber.