DUAL TRIM VALVE CARTRIDGE AND SYSTEM

Abstract

A valve system having a dual trim valve assembly capable of using a single valve assembly to provide fuel in a plurality of modes for at least a main burner operation mode and a parallel pilot operation mode.

Claims

1. A dual trim valve apparatus, the apparatus comprising: a main body having an inlet and one or more outlets; a first main valve control seat located within the main body; a second bypass valve control seat also located within the main body; a main control plug positioned within the main body and configured to selectively seal against the first main valve control seat; a bypass control plug positioned within the main body and configured to seal against the first main valve control seat; a main fluidic channel connecting the inlet to at least one outlet, the main fluidic channel providing fluid communication between the inlet and the at least one outlet, the main fluidic channel being sealed when the main control plug is sealed against the first main valve control seat; and a bypass fluidic channel connecting the inlet to at least one outlet, the bypass fluidic channel providing fluid communication between the inlet and the at least one outlet, the bypass fluidic channel being configured to selectively seal when the bypass control plug is sealed against the second bypass valve control seat.

2. The apparatus of claim 1, further comprising: a seat cartridge containing the first main valve control seat disposed within a perimeter portion of the seat cartridge, the seat cartridge also containing the second bypass valve control seat about a central portion, the seat cartridge being engageable with an interior portion of the main body.

3. The apparatus of claim 2, wherein the seat cartridge further includes at least one fluidic channel configured to provide fluid communication from the bypass fluidic channel to an exterior portion of the seat cartridge.

4. The apparatus of claim 1, further comprising a stem assembly, the stem assembly further comprising; a stem shaft, having the bypass fluidic channel passing through a central portion thereof; first and second stops provided along an outer circumference of the stem shaft at different axial heights; wherein the bypass control plug is situated about a distal end of the stem shaft and is configured to seal against the second bypass control seat within the main body so as to selectively seal the bypass fluidic channel by axially translating the stem shaft; and wherein the main control plug is slidingly engaged about an outer circumference of the stem shaft, the main control plug being disposed between the first and second stops, wherein movement of the stem shaft in an axial direction causes the first stop to engage the main control plug and push the main control plug out of the first main valve control seat allowing for fluid communication through the main fluidic channel, and wherein movement of the stem in an opposing axial direction causes the second stop to engage the main control plug and push the main control plug into the first main valve control seat restricting or sealing fluid communication through the main fluidic channel.

5. The apparatus of claim 4, further comprising: a seat cartridge containing the first main valve control seat disposed within a perimeter portion of the seat cartridge, the seat cartridge also containing the second bypass valve control seat about a central portion, the seat cartridge being engageable with an interior portion of the main body.

6. The apparatus of claim 5, further comprising: a bonnet cartridge having a central aperture configured to receive a proximal end of the stem shaft, the bonnet cartridge being engageable with an interior portion of the main body; and a spring configured to abut against an interior portion of the bonnet cartridge and abut against the main control plug thus biasing the main control plug into the first main valve control seat.

7. The apparatus of claim 6, further comprising: an aperture in a sidewall of a central portion of the stem providing fluid communication between the inlet of the valve main body and the bypass fluidic channel passing through a central portion of the stem.

8. The apparatus of claim 5, further comprising: an outlet pressure port provided on the valve main body configured to selectively provide access to an interior portion of the outlet of the valve main body; and at least one fluidic channel provided within the seat cartridge, the at least one fluidic channel being configured to provide fluid communication from the bypass fluidic channel and into the outlet pressure port, or to an exterior portion of the valve main body.

9. An integrated dual trim burner and pilot valve system, the system comprising: a main body having an inlet, a main outlet, and a bypass outlet; a first main valve control seat located within the main body; a second bypass valve control seat also located within the main body; a main control plug positioned within the main body and configured to selectively seal against the first main valve control seat; a bypass control plug positioned within the main body and configured to seal against the first main valve control seat; a main fluidic channel connecting the inlet to at least one outlet, the main fluidic channel providing fluid communication between the inlet and the at least one outlet, the main fluidic channel being sealed when the main control plug is sealed against the first main valve control seat; a bypass fluidic channel connecting the inlet to at least one outlet, the bypass fluidic channel providing fluid communication between the inlet and the at least one outlet, the bypass fluidic channel being configured to selectively seal when the bypass control plug is sealed against the second bypass valve control seat; and an actuator configured to selectively open or close both the main fluidic channel and the bypass fluidic channel, the bypass fluidic channel being configured to open independently from the main fluidic channel.

10. The system of claim 9, further comprising: a stem assembly, the stem assembly further comprising; a stem shaft, having the bypass fluidic channel passing through a central portion thereof; first and second stops provided along an outer circumference of the stem shaft at different axial heights; wherein the bypass control plug is situated about a distal end of the stem shaft and seal against the second bypass control seat within the main body so as to selectively seal the bypass fluidic channel by axially translating the stem shaft; and wherein the main control plug is slidingly engaged about an outer circumference of the stem shaft, wherein movement of the stem shaft in an axial direction causes the first stop to engage the main control plug and push the main control plug out of the first main valve control seat allowing for fluid communication through the main fluidic channel, and wherein movement of the stem in an opposing axial direction causes the second stop to engage the main control plug and push the main control plug into the first main valve control seat restricting or sealing fluid communication through the main fluidic channel.

11. The system of claim 10, further comprising: a seat cartridge containing the first main valve control seat disposed within a perimeter portion of the seat cartridge, the seat cartridge also containing the second bypass valve control seat about a central portion, the seat cartridge being engageable with an interior portion of the main body.

12. The system of claim 11, further comprising: a bonnet cartridge having a central aperture configured to receive a proximal end of the stem shaft, the bonnet cartridge being engageable with an interior portion of the main body; and a spring configured to abut against an interior portion of the bonnet cartridge and abut against the main control plug thus biasing the main control plug into the first main valve control seat.

13. The system of claim 12, further comprising: an aperture in a sidewall of a central portion of the stem providing fluid communication between the inlet of the valve main body and the bypass fluidic channel passing through a central portion of the stem.

14. The system of claim 13, further comprising: a burner being connected to the main outlet of the valve main body configured to be operable in a slipstream configuration; an outlet pressure port provided on the valve main body configured to selectively provide access to an interior portion of the main outlet the valve main body; at least one fluidic channel provided within the seat cartridge being configured to provide fluid communication from the bypass fluidic channel and into the outlet pressure port, or to an exterior portion of the valve main body; and a regulator provided downstream of the bypass fluidic channel before the outlet pressure port.

15. The system of claim 13, further comprising: an external pilot burner being connected to the bypass outlet; at least one fluidic channel provided within the seat cartridge being configured to provide fluid communication from the bypass fluidic channel to the bypass outlet and thus to the parallel pilot burner; and a regulator provided downstream of the bypass fluidic channel before the parallel pilot burner.

16. A method of providing fuel to a pilot and burner system using an integrated dual trim burner and pilot valve system, the method comprising: providing a valve having an inlet and a main outlet and a bypass outlet, the valve also having a first main valve control seat located within the main body and a second bypass valve control seat also located within the main body, the valve also having a main control plug configured to selectively seal against the first main valve control seat as well as a bypass control plug configured to seal against the first main valve control seat; the valve also having a main fluidic channel connecting the inlet to at least one outlet, the main fluidic channel providing fluid communication between the inlet and the at least one outlet, the main fluidic channel being sealed when the main control plug is sealed against the first main valve control seat; the valve also having a bypass fluidic channel connecting the inlet to at least one outlet, the bypass fluidic channel providing fluid communication between the inlet and the at least one outlet, the bypass fluidic channel being configured to selectively seal when the bypass control plug is sealed against the second bypass valve control seat; providing a fluid fuel to the inlet; partially actuating the valve by pulling on a proximal end of a stem shaft, thus allowing fluid to pass through the bypass fluidic channel provided through an interior portion of the stem shaft and thus provide fuel to a downstream burner; and fully actuating the valve by further pulling on a proximal end of a stem shaft, thus causing a first stop to engage the main control plug and dislodge the main control plug from the first main valve control seat.

17. The method of claim 16, further comprising: sealing the main fluidic channel by partially pushing the stem shaft into the valve main body thus allowing a spring to reseat the main control plug into the first main valve control seat; and sealing the bypass fluidic channel by pushing the stem shaft such that a force from an actuator provides the force to cause the bypass control plug to engage and seal against the second bypass valve control seat.

18. The method of claim 16, further comprising: regulating the pressure of the fluid fuel passing through the bypass fluidic channel and to the downstream burner using a regulator provided between the bypass fluidic channel and the downstream burner.

19. The method of claim 18, further comprising: wherein the fluid fuel is provided to the inlet at a pressure between 15 and 35 psi; and regulating the pressure provided to the downstream burner to between 3 and 6 psi using the regulator provided between the bypass fluidic channel and the downstream burner.

20. The method of claim 18, further comprising: wherein the downstream burner is a main burner and the pilot bypass fluidic channel is configured to operate a burner in a slipstream configuration; and reintroducing fluid fuel flowing through the bypass fluidic channel into the main outlet so as to feed fuel to the main burner.

21. The method of claim 18, further comprising: wherein the downstream burner is an external pilot burner and the pilot bypass fluidic channel is configured to operate a burner in an external pilot configuration.

22. A dual trim valve cartridge comprising: a bonnet cartridge configured for receiving a stem assembly; a stem assembly having a first plug and a second plug; and a seat cartridge having a first seat and a second seat; wherein the first plug is configured to operatively engage the first seat and the second plug is configured to operatively engage the second seat.

23. The valve cartridge of claim 22, wherein the stem assembly includes a stem shaft, the stem shaft having a bypass fluidic channel passing through a central portion of the stem shaft.

24. The valve cartridge of claim 23, wherein the stem assembly and the seat cartridge are configured to permit the first plug to independently engage the first seat and the second plug to independently engage the second seat.

25. The valve cartridge of claim 23, wherein the first seat is disposed within the seat cartridge within a perimeter portion of the seat cartridge, and wherein the second seat is disposed within the seat cartridge about a central portion.

26. The valve cartridge of claim 22 further comprising a main body having an inlet and an outlet, wherein the bonnet cartridge and the seat cartridge are engageable within the main body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Various embodiments of the present invention are shown and described in reference to the numbered drawings wherein:

[0015] FIG. 1 illustrates a dual trim valve system configured in a parallel pilot configuration in accordance with one or more aspects of the present invention;

[0016] FIG. 2a illustrates a dual trim valve system configured in a slip stream configuration in accordance with one or more aspects of the present invention;

[0017] FIG. 2b shows a cross-sectional view of the valve actuator assembly and the dual trim valve assembly of the valve system of FIG. 2a in accordance with one or more aspects of the present invention;

[0018] FIG. 3 shows an external isometric view of a dual trim valve assembly in accordance with one or more aspects of the present invention;

[0019] FIG. 4 shows a partially exploded external isometric view of a dual trim valve assembly in accordance with one or more aspects of the present invention illustrating various valve assembly components disposed within the valve body;

[0020] FIG. 5 shows a side cross sectional view of the dual trim valve assembly of FIG. 3 in a fully closed orientation in accordance with one or more aspects of the present invention;

[0021] FIG. 6 shows a side cross sectional view of the dual trim valve assembly of FIG. 3 in a bypass or pilot orientation in accordance with one or more aspects of the present invention;

[0022] FIG. 7 shows a side cross sectional view of the dual trim valve assembly of FIG. 3 in a fully open orientation in accordance with one or more aspects of the present invention;

[0023] FIG. 8 shows an isometric exploded view of a bonnet cartridge and stem assembly of a dual trim valve cartridge in accordance with one or more aspects of the present invention;

[0024] FIG. 9 shows an isometric exploded view of a seat cartridge of a dual trim valve cartridge in accordance with one or more aspects of the present invention;

[0025] FIGS. 10a-b show an isometric and a top view respectively of the seat cartridge of FIG. 9 in accordance with one or more aspects of the present invention;

[0026] FIG. 11 shows a bottom partial cross-sectional view of the seat cartridge of FIG. 9 in accordance with one or more aspects of the present invention;

[0027] FIG. 12a shows a perspective view of an assembled dual trim valve cartridge in accordance with one or more aspects of the present invention; and

[0028] FIG. 12b shows a cross-sectional view of the assembled dual trim valve cartridge of FIG. 12a in accordance with one or more aspects of the present invention.

[0029] It will be appreciated that the drawings are illustrative and not limiting of the scope of the invention which is defined by the appended claims. The embodiments shown accomplish various aspects and objects of the invention. It is appreciated that it is not possible to clearly show each element and aspect of the invention in a single figure, and as such, multiple figures are presented to separately illustrate the various details of the invention in greater clarity. Similarly, not every embodiment need accomplish all advantages of the present invention.

DETAILED DESCRIPTION

[0030] The invention and accompanying drawings will now be discussed so as to enable one skilled in the art to practice the present invention. The drawings and descriptions are exemplary of various aspects of the invention and are not intended to narrow the scope of the appended claims.

[0031] Turning now to FIGS. 1 and 2. Shown are two different configurations of a dual trim valve system which uses a dual trim valve assembly in accordance with one or more aspects of the present invention. FIG. 1 illustrates a dual trim valve system 10 for use with a standard burner and parallel pilot system. The dual trim valve system 10 can include a valve actuator assembly 30, one or more shutoff valves 20, a dual trim main control valve 100, and a pilot regulator 40 which controls the pressure and gas flow for the parallel or pilot/bypass gas flow which supplies gas to the parallel pilot (not shown). In this embodiment, the dual trim main control valve 100 is configured to provide a parallel/bypass gas flow 50 which selectively provides gas through the bypass 50 to a parallel pilot burner through a bypass fluidic channel through the dual trim valve 100. The dual trim valve is operational in 3 separate modes, the modes being selectively chosen by means of the valve actuator assembly 30. The first mode is provided as a completely shut-off configuration wherein both the pilot/bypass gas flow operating the pilot, and the main burner gas supply operating the main burner are closed off from the main gas supply. The second mode is an intermediate mode wherein the main burner gas supply is still closed to the main gas supply but the pilot/bypass gas flow is open to allow gas to flow to the parallel pilot (not shown) downstream from the pilot regulator 40. The third mode being where both the bypass gas flow 50 and the main burner gas supply 70 are fully open to the main gas supply 60 supplying gas to a main burner (not shown) being located downstream from the valve 110, as well as to the parallel pilot (not shown).

[0032] FIG. 2a illustrates a dual trim valve system 12 configured for slipstream pilot functionality. The dual trim valve system 12 can include a valve actuator assembly 30, one or more shutoff valves 20, a dual trim main control valve 100, and a pilot regulator 40 which controls the pressure and gas flow for the parallel or pilot/bypass gas flow 50 which supplies gas to a slipstream style pilot/burner assembly (not shown) wherein the pilot function operates by way of a reduced pressure and burner power configuration of the main burner. The dual trim valve 100 is configured to provide a bypass gas flow 50 wherein the dual trim valve 100 selectively provides gas through the bypass gas flow 50 and back into the burner gas supply 70 through a bypass fluidic channel which passes through the dual trim valve 100. The dual trim valve 100 is operational in 3 separate modes, the modes being selectively chosen by means of the valve actuator assembly 30. The first mode is provided as a completely shut off configuration wherein both the bypass gas flow, and the main burner gas supply operating the main burner are closed off from the main gas supply. The second mode is an intermediate mode wherein the main burner gas supply is still closed to the main gas supply, but the bypass gas flow is open to allow gas to flow to the main burner (not shown) in a low power/pressure slipstream mode, the main burner being connected downstream from the regulator 40. The third mode being where both the bypass gas flow 50 and the main burner gas supply 70 are fully open to the main gas supply 60.

[0033] It will be appreciated that pilots typically operate at a lower pressure than the main gas supply, e.g., at about 5 psi versus the main gas supply which may operate at about 20 psi. The pilot regulator 40 being located on the bypass gas flow line 50 so as to regulate the pressure for the reduced power slipstream configuration or the parallel pilot configuration as necessary to operate the burner/pilot from the main supply and associated pressure.

[0034] FIG. 2b illustrates a valve actuator assembly 30 connected to a dual trim valve assembly 100 in accordance with one or more aspects of the present invention. The valve actuator assembly 30 may be used for actuating the dual trim valve to control fuel flow and to select the fuel flow mode. As shown in the Figures, the actuator assembly may be comprised of a control motor 32 disposed within an explosion proof housing 34, a mounting base 38 to which actuator assembly components may be mounted or secured, a yoke 39 for mounting the actuator assembly to the dual trim valve assembly 100, and an actuator rod 500 that is operably connected to the control motor 32. The control motor may be a direct drive or stepper motor. The actuator rod is connected to a motor drive component of the control valve motor using a coupling block 37, which may be disposed in a motor guide mount 36. The motor may be mounted on top of the motor guide mount 36. A motor driver control may be disposed adjacent to the control valve motor 22 and operably connected to the motor to permit the driver control to direct the motor to move the actuator rod 500 up or down in response to signals received by the driver from a burner management system in response to pressure or temperature conditions within a combustion application. The motor guide mount 36 may be secured to the top side of the mounting base 38. The valve actuator assembly 30 engages the dual trim valve. The actuator rod 50 extends from the coupling block 37 through an opening in the top side of the mounting base 38 and extends between the legs of the yoke 39 where, as shown in FIG. 2b, it may be secured to a valve stem 410 using a stem clamp.

[0035] FIGS. 3-4 illustrate the dual trim valve assembly 100 being separate from the rest of the dual trim valve systems of FIGS. 1, 2a and 2b. It will be appreciated that the valve actuator (not shown here) operates to pull or push on the stem assembly 400. The stem assembly can slide axially through the main body 110 of the dual trim valve assembly 100. A bonnet cartridge 200 operates to seal the gas which is provided to the main inlet 114 from escaping around the stem assembly and out of the main body 110. The main body 110 can be provided with attachment means 130 so as to attach a desired valve actuator (not shown). The main body can further be provided with a seat cartridge 300 which can provide various valve control seats for both the bypass mode and the main supply mode, which will be discussed in more detail below.

[0036] The main body 120 can also be provided with a main outlet 118 which supplies gas to a main burner (not shown), as well as with a bypass outlet (not shown) which can be configured to exit from the seat cartridge 300.

[0037] The main body 110 can also be provided with an inlet pressure port 122 which provides access, or a potential fluidic channel which is upstream from any valve control within the dual trim valve 100. Additionally, the main body 110 can also be provided with an outlet pressure port 126 which provides access, or a potential fluidic channel which is downstream from any valve control within the dual trim valve 100. The slipstream configuration, as discussed with reference to FIG. 2a, can provide a fluid connection between the bypass outlet configured to exit from the seat cartridge 300 and into the outlet pressure port 126 so as to bypass the main control of the dual trim valve 100.

[0038] FIG. 5 illustrates the dual trim valve assembly 100 in a first configuration wherein the valve is in a completely sealed or closed state. In this configuration the main inlet 114 is sealed from providing any gas through the main body 110. In this view is illustrated one embodiment for providing a bypass through the main body 110. In this embodiment the stem assembly is provided with a bypass fluidic channel 444 which has an inlet in on the inlet side of the main body passes through a central portion of the stem shaft assembly 400 and has an outlet which is part of the bypass control plug 440 being located about a distal end of a stem shaft 410. In the closed configuration the bypass control plug 440 is pressed against the second bypass valve control seat 370 which is located about a lower and central portion of the seat cartridge 300. The second bypass valve control seat 370 can be provided with a sealing disc 360, which is formed of a soft material to aid in the sealing between the second bypass valve control seat 370 and the bypass control plug 440, the soft material of the sealing disc being comprised of rubber in a preferred embodiment. This configuration also illustrates how in the sealed configuration the bypass control plug 440 is seated into second bypass valve control seat 370 and thus seals and prohibits the flow of gas from the inlet 114 to the cartridge bypass channels 374 which can be used to provide fuel/gas to the slipstream fuel passage or to the pilot, as discussed above.

[0039] This configuration also illustrates how in the sealed configuration the main control plug 450 is seated into the main valve control seat 334 and thus seals and prohibits the flow of gas from the inlet 114 to the outlet 118. The spring 230 can aide in providing a sealing force pushing against bonnet cartridge 200 thus pushing the main control plug 450 into the main valve control seat 224. The sealing force can be increased by providing a second stop 416 along the outer circumference of the stem shaft 410 above the main control plug 450, which, when pushed down can transfer force from the valve actuator (not shown) into the main control plug 450 and increase the sealing force between the main control plug 450 and main valve control seat 334.

[0040] FIG. 6 illustrates the dual trim valve assembly 100 in a second configuration wherein the valve is in an intermediate state, wherein the valve actuator (not shown) has provided a tensile force on a proximal end of the stem shaft 410 and translated the stem shaft axially a small distance. In this configuration the main inlet 114 is no longer fully sealed and can provide a small amount of fuel/gas through the main body 110. In this configuration the bypass control plug 440 is no longer pressed against the second bypass valve control seat 370 which opens the bypass fluidic channel into open communication with the cartridge bypass channels 374 and thus allowing fuel/gas to pass therethrough. In this configuration the main control plug 450 is still seated into the main valve control seat 334 and still restricts flow of supply fuel/gas from the inlet 114 and main gas supply 60 to the outlet 118. The spring 230 can aide in providing a sealing force pushing against bonnet cartridge 200 thus pushing the main control plug 450 into the main valve control seat 224. It will be appreciated that a first stop, which is provided about the outer circumference of the stem shaft 410 below the main control plug 450 has not yet engaged the main control plug 450 to unseat it from the main valve control seat 334.

[0041] FIG. 7 illustrates the dual trim valve assembly 100 in a third configuration in which the valve is in a fully open state, wherein the valve actuator (not shown) has provided a tensile force on a proximal end of the stem shaft 410 and translated the stem shaft a farther distance. In this configuration the bypass control plug 440 is unseated from the second bypass valve control seat 370 and the main control plug 450 is also unseated from the main valve control seat 334 allowing pilot gas flow 50 and main burner gas supply 70 to both flow through the valve. In this configuration, the first stop 412 has engaged the main control plug 450 causing it to translate upward with the moving stem shaft 410. This translation causes the spring 230 to at least partially compress and the main control plug 450 to unseat from the main valve control seat 334 thus opening the main fluidic channel.

[0042] FIGS. 12a and 12b illustrate a perspective view and a cross-sectional view respectively of a dual trim valve cartridge in accordance with one or more aspects of the present invention. The dual trim valve cartridge may be disposed within the main body 120 of the dual trim valve assembly 100. The dual trim valve cartridge may be secured within the main body 120 by loading the seat cartridge 300 into a bottom threaded cavity of the main body 120 by turning or threading the seat cartridge into the bottom cavity. The bonnet cartridge 200 and stem assembly 400 of the dual trim valve cartridge may be loaded in a top cavity of the main body 120 of the dual trim valve assembly 100 and secured using a snap ring 252.

[0043] FIGS. 8, 9, 10a-10b, and 11 show exploded, isometric, and partial cross-sectional views of components of the dual trim valve cartridge and can better illustrate how the different components are assembled an can work together.

[0044] FIG. 8 is an exploded view of the bonnet cartridge 200, spring 230, and the stem assembly 400. The bonnet cartridge 200 can include a bonnet cartridge body 240. The bonnet cartridge body 240 carries various seals and allows for the stem shaft 410 of the stem cartridge to easily move through it and seal the interior of the valve from the valve actuator which operates to move the stem shaft 410 from outside the main body of the valve while providing the necessary actuation to plugs about the interior of the valve. The bonnet cartridge 200 can also have a bonnet cartridge seal 242 disposed in a bonnet cartridge seal groove around the exterior circumference of the bonnet cartridge body 240 to prevent fuel from escaping or leaking between the bonnet cartridge body 240 and the walls of the top cavity of the main body 120 of the dual trim valve assembly 100. The interior of the bonnet cartridge includes a stem bushing 244, one or more seal rings 246a, 246b, preferably quad seal rings, and a stem guide 248 and a bonnet seal retaining ring 250, i.e. a snap ring, can hold these components into the interior of the bonnet cartridge. The stem bushing and the stem guide provide smooth axial translation of the stem shaft 410 through the bonnet cartridge while the seal rings prevent gas from escaping between the stem shaft 410 and the interior of the bonnet cartridge body 240. Then the stem assembly 400 can be inserted into the main body, the bonnet cartridge can be slid over the proximal end of the stem shaft 410 and slit into the main body and held into the main body using the bonnet retaining ring 252.

[0045] The stem assembly 400 can include a stem shaft 410 having proximal and distal ends. The proximal end being the upper end which protrudes from the main body 120 of the valve assembly 100 and through the bonnet cartridge 200 for connecting to a valve actuator. The stem shaft 410 can be provided with the bypass fluidic channel 444 passing therethrough and out a bottom or distal end of the stem shaft 410. The outer circumference can be provided with various grooves for receiving various seals or components. These channels include a first stop groove 414 configured to receive a first stop 412. This first stop 412 operates to un-seat the main control plug 450 from the main valve control seat (not shown) as discussed above. The channels also include a second stop groove 414 for receiving the second stop 416 which operates to aid in pushing the main control plug 450 into the main valve control seat (not shown). A second seal groove 426 can also be provided and configured to receive a second stem seal 424. The second stem seal operates to seal between the stem shaft 410 and an interior portion of the main control plug 450 as the main control plug slides along the outer surface of the stem shaft 410. This seal prevents fuel/gas from leaking through from the inlet side of the main body to the outlet side of the main body by passing between the main control plug 450 and the stem shaft 410 particularly in the closed configuration.

[0046] The stem shaft can also be provided with a first seal groove 422 configured to receive the first stem seal 420. This seal operates to outer circumference of the stem shaft 410 against an interior portion of the seat cartridge. This seal is configured to prevent the flow of gas from the bypass fluidic channel 444 out of the bottom of the stem shaft 410 and into the main outlet portion of the main body.

[0047] The main control plug 450 is also provided with a main seal ring groove 454 configured to receive a main plug seal ring 452. The main plug seal ring 452 operates to aide in the sealing of the main control plug 450 against the main valve control seat (not shown). As discussed below, the main valve control seat can be tapered such that the main seal ring 452 contacts the main valve control seat prior to the material forming the body of the main control plug.

[0048] The spring 230 is mounted in compression between the bottom surface of the bonnet cartridge 200 and the main control plug 450 and operates to press press the main control plug 450 downward on the stem shaft 410 so as to bias the main control plug 450 in a downward direction toward the main valve control seat when assembled.

[0049] FIGS. 9-11 illustrate various exploded and assembled views of the seat cartridge 300. The seat cartridge 300 can include a seat cartridge body 310. The seat cartridge body 310 can be provided with a set of main threads for engaging female threads provided in a lower interior portion of the valve body so as to engage and retain the seat cartridge 300 therein. The seat cartridge can have an upper portion which includes one or more main cartridge channels 314 which allow provide a main flow path from the inlet of the main valve body to the outlet of the main body 120. At an upper portion of the seat cartridge about an interior surface of a circumferential portion is provided a tapered surface for receiving a seat ring 330. The seat ring 330 can have a seat ring groove 332 for receiving a seat ring seal and thus sealing the outer portion of the seat ring 330 to the interior surface of the seat cartridge body 310 so as to prevent leaking of gas between the valve control seat body 310 and the seat ring 330 which can result in undesirable leaking from the inlet side of the valve body to the outlet side of the valve body. The seat ring and seal can be held tightly into the interior of the seat cartridge body by using a seat cartridge retaining ring 304, i.e. a snap ring. The seat ring 330 can have a tapered interior surface which operates as the main valve control seat 334. This tapered surface can be configured with an appropriate slope such that the main seal ring of the main control plug contacts the surface prior to the main material of the main control plug body. It will be appreciated that the main valve control seat is above and between an inlet side of the valve and the main cartridge channels 314 when assembled.

[0050] The seat cartridge can further include a lower sealing groove 346 configured to receive a lower cartridge O-ring 350. The lower cartridge O-ring 350 is configured to be drawn up as the threads engage and then seal against an outer portion of the valve's main body thus preventing gas from leaking out of the valve. The seat cartridge can also include an upper sealing groove 348 configured to receive an upper cartridge O-ring 352. The upper cartridge O-ring 352 is configured to seal the outer circumference of the seat cartridge against an interior surface of the valve main body so as to seal an inlet portion of the main body from the outlet portion of the main body and prevent gas from leaking around the seat cartridge, particularly in the closed configuration. It will also be appreciated that the downward force of the main control plug into the tapered surface of the main valve control seat can operate to provide a radial seal by compressing the main plug seal ring 452 against the interior surface of the main valve control seat 334.

[0051] The seat cartridge 300 can include a second bypass valve control seat 370 located at a lower and central portion of the seat cartridge body 310. The bypass valve control seat 370 can also include a bypass seat seal, which can be provided as a rubber or fibrous disc which operates to seal about the tip of the distal end of the stem shaft thus sealing any flow from passing through the bypass fluidic channel. When opened, i.e. when the stem shaft is pulled upward, fuel/gas can flow into the chamber created between the seat cartridge and the stem shaft and then flow out of the cartridge bypass channel 374. The cartridge bypass channel 374 can include a plurality of channels which can be configured to exit through a bottom end of the seat cartridge body 310. It will be appreciated that the seat cartridge body 310 can be provided with a female threaded portion about where the cartridge bypass channel 374 exits the seat cartridge body 310 such that necessary piping can carry the fuel/gas to a necessary downstream points, i.e. to a regulator and then to a parallel pilot, or back into the main gas supply for the slipstream configuration.

[0052] The above description is merely illustrative. Having thus described several aspects of at least one embodiment of this invention including the preferred embodiment, it is to be appreciated that various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description and drawing are by way of example only.