CA2976419A1 - Relief valve - Google Patents

Relief valve Download PDF

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Publication number
CA2976419A1
CA2976419A1 CA2976419A CA2976419A CA2976419A1 CA 2976419 A1 CA2976419 A1 CA 2976419A1 CA 2976419 A CA2976419 A CA 2976419A CA 2976419 A CA2976419 A CA 2976419A CA 2976419 A1 CA2976419 A1 CA 2976419A1
Authority
CA
Canada
Prior art keywords
ball
support surface
conduit
spring
relief valve
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA2976419A
Other languages
French (fr)
Other versions
CA2976419C (en
Inventor
Bertito Tubo Rodriguez
Gregory Dean Goodson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Aalberts Integrated Piping Systems Americas Inc
Original Assignee
Conbraco Industries Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Conbraco Industries Inc filed Critical Conbraco Industries Inc
Publication of CA2976419A1 publication Critical patent/CA2976419A1/en
Application granted granted Critical
Publication of CA2976419C publication Critical patent/CA2976419C/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16KVALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K27/00Construction of housing; Use of materials therefor
    • F16K27/02Construction of housing; Use of materials therefor of lift valves
    • F16K27/0245Construction of housing; Use of materials therefor of lift valves with ball-shaped valve members
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16KVALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K15/00Check valves
    • F16K15/02Check valves with guided rigid valve members
    • F16K15/04Check valves with guided rigid valve members shaped as balls
    • F16K15/044Check valves with guided rigid valve members shaped as balls spring-loaded
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16KVALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K17/00Safety valves; Equalising valves, e.g. pressure relief valves
    • F16K17/02Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side
    • F16K17/04Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded
    • F16K17/0406Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded in the form of balls
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16KVALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K27/00Construction of housing; Use of materials therefor
    • F16K27/02Construction of housing; Use of materials therefor of lift valves
    • F16K27/0209Check valves or pivoted valves

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Safety Valves (AREA)

Abstract

A relief valve for relieving pressure in a fluid conduit that includes a cradle positioned in the relief valve conduit and having a ball support surface and a ball mounted on the ball support surface and adapted for sealing against the valve seat of the pressure relief port. A spring support surface and a spring positioned in the pressure relief conduit urges the cradle and the ball into sealing position against the valve seat of the pressure relief port.

Description

RELIEF VALVE
Technical Field and Background of the Invention This application relates to a relief valve used to relieve pressure in a pressurized fluid system. The novel relief valve is described in this application for purposes of illustration and explanation as being installed on a water heater shutoff/thermal expansion control valve such as an Apollo 78T .F-RV Series valve manufactured by Conbraco Tndustries, Inc.
of Matthews, North Carolina. However, the relief valve has application in a wide variety of uses, and its description in this application installed on a specific device carries no implication that its use is limited to use on that device.
Conventional relief valves include a body that is positioned in fluid communication with a pressurized fluid system, for example a shutoff valve, backflow valve, or pipe. A
spring-loaded rubber ball bears against the walls of a relief port in the valve, pipe, etc. The spring is designed for a specific relief setting. If pressure in the system exceeds a predetermined value, that excessive pressure exerts sufficient force against the ball to unseat it from the relief port walls, allowing fluid to flow past the ball to atmosphere, an expansion tank or other resorvoir. As the pressure is reduced, the ball is again, urged back into sealing contact with the wall of the relief port. The spring is mounted in a conduit in the relief valve and is held in an aligned position by the walls of the conduit and a shoulder of reduced diameter against which the end of the spring remote from the ball resides.
These prior art relief valves are prone to delivering inaccurate performance as a result of the spring being compressed during an over pressure event to the extent that the coils contact each other and the spring becomes, iii practical effect, a solid object that restricts fluid flow from the valve.
This condition can result in false pressure readings, delayed pressure relief and simi.lar conditions,
2 Summary of the Invention Therefore, it is an object of the invention to provide a pressure relief valve that provides accurate, reliable and rapid pressure relief in a pressurized fluid system to which the relief valve is attached.
It is another object of the invention to provide a pressure relief valve that permits pressure relief by full fluid flow from a fluid system hi an over pressure condition.
It is another object of the invention to provide a pressure relief valve that provides support to the sealing ball during both seated and unsealed positions.
It is another object of the invention to provide a pressure relief valve that prevents defOrmation of the ball in both sealed and unsealed positions.
These and other objects and advantages of the present invention are achieved in the preferred embodiment disclosed below by providing a relief valve for relieving pressure in a fluid conduit that includes a valve body adapted for being positioned in fluid communication with a fluid pressure system. A relief valve conduit is formed in the relief valve body and has a valve seat positioned around a pressure relief port at one end of the conduit adapted for communication with the fluid pressure system and a discharge vent in an opposite end of the conduit. A cradle is positioned in the relief valve conduit and includes a ball support surface with a hall mounted on the ball support surface and adapted for sealing against the valve seat of the pressure relief pert. A spring support surface is provided normal to a longitudinal axis of the relief valve conduit, The spring is positioned in the pressure relief conduit for urging the ball carried in the cradle into scaling position against the valve seat of the pressure relief port, The spring has .a predetermined load, When pressure is exerted on the spring in excess of the wedeermined load, the spring will compress, withdrawing the ball out of sealing position against the valve seat of the pressure relief port to allow a discharge of fluid from the
3 fluid pressure system, According to another embodiment of the invention, the cradle includes a pair of spacers positioned between the ball support surface and the spring support surface.
According to another embodime-nt of the invention, the cradle includes a pair of spacers positioned between the ball support surface and the spring support surface and at least one flow port for permitting fluid flow through and around the cradle.
According to another embodiment of the invention, the bail support surface of the cradle includes an annular scgmcnt corresponding in shape to a portion of the surface of the ball.
According to another embodiment of the invention, the spring support surface includes a planar surface defined by an inner and outer circumference of the cradle.
According to another embodiment of the invention, the relief valve conduit includes a shoulder of reduced diameter for supporting an end of the spring remote from the ball.
According to another embodiment of the invention, the ball is fabricated of ethylene propylene diene monomer.
According to another embodiment of the invention, the Wilms a 70 Shore A
bardru.',ss.
According to another embodiment of the invention, the spring has a compression of about 50 percent between a free length and a fully compressed length.
According to another embodiment of the invention, a relief valve is provided for relieving pressure in a fluid conduit, and includes a valve body adapted for being positioned in fluid communication with a fluid pressure system and a relief valve conduit formed in the relief valve body having a valve seat positioned around u pressure relief port at orro end of the conduit adapted for communication with the fluid pressure system and a discharge vent in an
4 opposite end of the conduit. A cradle is positioned in the relief valve conduit and includes a bail support surface and a ball mounted on the ball support surface adapted for sealing against the valve seat of the pressure relief port. The ball support surface of the cradle includes an annular segment conesponding in shape to a portion of the surface of the ball.
A spring support surface normal to a longitudinal axis of the relief valve conduit has a planar defined by an inner and outer circumference. A spring is positioned in the pressure relief conduit for urging the cradle and the, ball into sealing position against the valve seat of the pressure relief port. The spring has a predetermined load in excess of which the spring will compress, withdrawing the hall out of sealing position against the valve seat of the pressure relief port to allow a discharge of fluid from the fluid pressure system. A pair of spacers Is positioned between the ball support surface and the spring support surface and at least one flow port for permitting fluid flow through and around the cradle. A shoulder of reduced diameter is formed in the relief valve conduit for supporting an end of the spring remote aom the hall, According to another embodiment of the invention, a water heater shutoffithermal expansion control valve adapted for being positioned in flow communication with a water pressure system is provided, and includes a pressure relief valve for relieving pressure in the system above a pTudetermined level. The pressure ref id valve Includes a valve body adapted for being positioned in fluid communication with a fluid pressure system. A
relief valve conduit is formed in the relief valve body and has a valve seat positioned around a pressure relief port at one end of the conduit adapted for communicatIon with the fluid pressure system and a discharge vent in an opposite end of the conduit. A cradle is positioned in the relief valve conduit and includes a ball support surface and a ball mounted on the ball support surface and adapted for scaling against the valve seat of the pressure relief port, A spring support surface normal to a longitudinal axis of the relief valve conduit is provided, and a spring is positioned in the pressure relief conduit for urging the cradle and the ball into sealing position against the valve seat of the pressure relief port. = The spring has a predetermined load in excess of which the spring will compress, withdrawing the ball out of sealing position against the valve seat of the pressure relief port to allow a discharge of fluid from the fluid pressure system, Brief Description of the Drawiogs Some of the objects of the invention have been set forth above, Other objects and advantages of the invention will appear as the description of the invention proceeds when taken in eon] unetion with the following drawings, in which:
Figure 1 is a vertical longitudinal cross section of a water heater shutoff/thermal expansion control valve equipped with a prior art pressure relief valve;
Figure 2 is a vertical longitudinal cross section of the prior art pressure relief valve of Figure 1 in a sealing position;
Figure 3 is a vertical longitudinal cross section of the prior art pressure relief valve of Figure 1 in an unsealed, pressure relief position;
Figure is a vertical longitudinal cross section of a water heater shutoff/thertnal expansion control valve equipped with a pressure relief valve according to a preferred embodiment of the invention;
Figure 5 is a side elevation view of the water heater shutoff/thermal expansion control valve of Figure 4, with the components of the pressure rul lel' valve shown in an exploded view;
Figure 6 is a vertical longitudinal cross section of the pressure relief valve of Figure 4 in a sealing position;

PC1'1US2015/015634 Figure 7 is a vertical longitudinal cross section of the pressure relief valve of Figure 4 in an unsealed, pressure relief position;
Figure 8 is an enlarged view of the ball and spring support cradle of the invention; and Figure 9 is a cross-section of the ball and spring support cradle shown in Figure R.
Description of the Preferred Embodiment and Best Mode Referring now to Figures I, 2 and 3 of the application, a water heater -shutoff/thermal expansion control valve 10 is shown, and includes a valve body 12 defining a conduit 14 that passes water from a supply connection 16 through the conduit 14 and out through a discharge connection 18 to, for example, a water beater, Valve 10 is controlled by a valve ball 20 rotated by a stem 22 connected to a quarter-turn handle 24.
A prior art relief valve 30 includes a valve body 32 that communicates with the conduit 14 through a chamfered relief port. 34 in The valve body 12, The valve body 32 defines a relief valve conduit 36 that vents fluid to atmosphere or a suitable reservoir, A
relief valve :fitting sub-assembly 38 is threaded onto the valve body 32 of the relief valve 30.
The valve body 32 defines a conduit 40 with a shoulder 42 that supports a spring 44 that directly contacts and urges a ball 46 against the relief port 34 to effect a scat during normal pressure operation of the valve 10, See Figure 2.
This design presents several disadvantages. First, rapid, accurao discharge is obstructed by tho coils of the spring 44 as water is vented to the atmosphere;
as shown in Figure 3. Delay in venting may result In a false reading or the discharge rate that fails to satisfy the performance requirements of TAPMO IGC 128-2008, Second, the ball 46 Is seated directly on the top of spring 44, The pressure of the spring 44 against the ball 46 can cause an impression on the surface of the ball 46 and, eventually damage to the surface, As the spring 44 impresses itself into the surface of the ball 46, the in-place length a the spring inereases and reduces the load applied to the ball 46 as the impression on the surface of the ball 46 increases.
Referring now to Figures 4-9, a relief valve 60 accordiug to the invention is shown in place on a valve 10 of the same design and operation as the valve 10 of Figures 1-3. Relief = valve 60 includes a valve body 62 that communicates with the conduit 14 through chamfered relief port 64 in the valve body 12. The relief valve body 62 defines a relief valve conduit 66 that vents fluid to atmosphere or a suitable reservoir. A relief valve fitting sub-assembly 6a is threaded onto the valve body 62 of the relief valve 60. See Figures 5, 6 and 7.
A hall 70 and spring 72 operate the relief valve 60, and as is shown in Figures 8 and 9, in accordance with the invention, a cradle 80 is provided and includes an.
annular ball support surface 82 and a ring-shaped, radially-extending spring support surface 84. The ball support surface 82 and spring support surface 84 are separated by a pair of spacers 86, 88 that define flow ports 90, 92.
Referring now to Figures 6 and 7, the spring 72 now engages the spring support surface 84 of the cradle 80 instead of the ball 70. The ball 70 is supported on the much larger surface area of the ball support surface 82. The ball 70 is uniformly urged against the relief port 64 by operation of the spring support surfaue 84. The ball 80 is preferably EPDM rubber (ethylene prnpylene dime monomer) with a 70 Shore A hardness. EPDM is a particularly appropriate material because of its resistance to softening and degradation by hot water.In one embodiment, the ball has a diameter of .250 in, (635 mm), the spring has a .390 in. (9 min) free length and a .213 in, (5,4 mm) uompressed length. The ball support surface 82 has a radius of ,125 in. (3.18 mm), and the spring support surface has an inner circumference of .260 in. (6.6 mm) and an outer circumference of 370 in, (9,4 mm), A relief valve is described above. Various details of the invention may be changed without departing from its scope. Furthermore, the foregoing description of the preferred embodiment of the invention and the best mode for practicing the invention are provided for the purpose of illustration only an4 not for the purpose of limitation¨the invention being = defined by the claims.

..= -

Claims (18)

We Claim:
1. A relief valve for relieving pressure in a fluid conduit, comprising:
(a) a valve body adapted for being positioned In fluid communication with a fluid pressure system;
(b) a relief valve conduit formed in the relief valve body and having a valve seat positioned around a pressure relief port at one end of the conduit adapted for communication with the fluid pressure system and a discharge vent in an opposite end of the conduit;
(0) a cradle positioned in the relief valve conduit and including:
a ball support surface and a ball mounted on the ball support surface and adapted for sealing against the valve seat of the pressure relief port; and (ii) a spring support surface normal to a longitudinal axis of the relief valve conduit and a spring positioned in the pressure relief conduit for urging the cradle and the ball into sealing position against the valve scat of the pressure relief port, the spring having a predetermined load in excess of which the spring will compress, withdrawing the ball out of sealing position against the valve seat of the pressure relief port to allow a discharge of fluid from the fluid pressure system.
2. A relief valve according to claim 1, wherein the cradle includes a pair of spacers positioned between the ball support surface and the spring support surface,
3. A relief valve according to claim 1, wherein the cradle includes a pair of spacers positioned between the ball support surface and the spring support surface and at least one flow port for permitting fluid flow through and around the cradle.
4. A relief valve according to claim 1, wherein the ball support surface of the cradle includes an annular segment corresponding in shape to a portion of the surface of the ball.
5. A relief valve according to claim 1, wherein the spring support surface comprises a planar surface defined by an inner and outer circumference of the cradle.
6. A relief valve according to claim 1, wherein the relief valve conduit includes a shoulder of reduced diameter for supporting an end of the spring remote from the ball.
7. A relief valve according to claim 1, wherein the ball comprises ethylene propylene diene monomer.
8. A relief valve according to claim 7, wherein the ball has a 70 Shore A
hardness.
9, A relief valve according to claim 1, wherein the spring has a compression of about 50 percent between a free length and a fully compressed length,
10. A relief valve tor relieving pressure in a fluid conduit, comprising:
(a) a valve body adapted for being positioned in fluid communication with a fluid pressure system;
(b) a relief valve conduit formed in the relief valve body and having a valve seat positioned around a pressure relief port at one end of the conduit adapted for communication with the fluid pressure system and a discharge vent in an opposite end of the conduit;
(c) a cradle positioned in the relief valve condu (I) a ball support surface and a ball mounted on the ball support surface and adapted for sealing against the valve seat of the pressure relief port, the ball support surface of the cradle including an annular segment corresponding in shape to a portion of the surface of the ball;
(ii) a spring support surface normal to a longitudinal axis of the relief valve conduit having a planar surface defined by an inner and outer circumference of the cradle, and a spring positioned in the pressure relief conduit for urging the cradle and the ball into sealing position against the valve seat of the pressure relief port, the spring having a predetermined load in excess of which the spring will compress, withdrawing the ball out of sealing position against the valve seat of the pressure relief port to allow a discharge of fluid from the fluid pressure system (iii) a pair of spacers positioned between the ball support surface and the spring support surface and at least one, flow port for permitting fluid flow through and around the cradle; and (d) a shoulder of reduced diameter termed in the relief valve conduit for supporting an end of the spring remote from the ball,
11. A water heater shutoff/thermal expansion control valve adapted for being positioned in flow communication with a water pressure system, and including pressure relief valve for relieving pressure in the system above a predetermined level, the pressure relief valve comprising:
(a) a valve body adapted for being positioned in fluid communication with a fluid pressure system;
(b) a relief valve conduit formed in the relief valve body and having a valve seat positioned around a pressure relief port at one end of the conduit adapted for communication with the fluid pressure system and a discharge vent in an opposite end of the conduit;
(c) a cradle positioned in the relief valve conduit and including:
(i) a ball support surface and a ball mounted on the ball support surface and adapted for sealing against the valve seat of the pressure relief port; and (ii) a spring support surface normal to a longitudinal axis of the relief valve conduit and a spring positioned in the pressure relief conduit for urging the cradle and the bail into sealing position against the valve seat of the pressure relief port, the spring having a predetermined load in excess of which the spring will compress, withdrawing the ball out of sealing position against the valve seat of the pressure relief port to allow a discharge of fluid from the fluid pressure system.
12. A wider heater shutoff/thermal expansion control valve according to claim 11, wherein the cradle includes a pair of spacers positioned between the ball support surface and the spring support surface.
13. A water heater shutoff/thermal expansion control valve according to claim 11, wherein the cradle includes a pair of spacers positioned between the ball support surface and the spring support surface and at least one flow port for permitting fluid flow through and around the cradle.
14. A water heater shutoff/thermal expansion control valve according to claim 11, wherein the ball support surface of the cradle includes an annular segment corresponding in shape to a portion of the surface of the ball.
15.A water heater shutoff/thermal expansion control valve according to claim 11, wherein the spring support surface comprises a planar surface defined by an inner and outer circumference of the cradle.
16. A water heater shutoff/thermal expansion control valve according to claim 11, wherein the relief valve conduit includes a shoulder of reduced diameter for supporting an end of the spring remote from the ball.
17. A water heater shutoff/thermal expansion control valve according to claim 11, wherein the ball comprises ethylene propylene diene monomer.
18. A water heater shutoff/thermal expansion control valve according to claim 17, wherein the ball has a 70 Shore A hardness.
CA2976419A 2015-02-12 2015-02-12 Relief valve Expired - Fee Related CA2976419C (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2015/015634 WO2016130129A1 (en) 2015-02-12 2015-02-12 Relief valve

Publications (2)

Publication Number Publication Date
CA2976419A1 true CA2976419A1 (en) 2016-08-18
CA2976419C CA2976419C (en) 2020-01-21

Family

ID=56615441

Family Applications (1)

Application Number Title Priority Date Filing Date
CA2976419A Expired - Fee Related CA2976419C (en) 2015-02-12 2015-02-12 Relief valve

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CA (1) CA2976419C (en)
WO (1) WO2016130129A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107940000B (en) * 2017-11-21 2019-05-10 新昌县澄聚农业科技有限公司 A kind of automobile specified hydraulic valve preparation method

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2470372A (en) * 1944-07-17 1949-05-17 Borg Warner Ball type pressure relief valve
US2481713A (en) * 1945-04-30 1949-09-13 Bertea Alex Flexible seal check valve
US4310018A (en) * 1980-02-13 1982-01-12 Parr Manufacturing Company Check valve assembly
US4930553A (en) * 1989-01-23 1990-06-05 The Lee Company Pressure relief valve
CN203718015U (en) * 2014-03-17 2014-07-16 宁波华成阀门有限公司 Ball valve with safety valve

Also Published As

Publication number Publication date
WO2016130129A1 (en) 2016-08-18
CA2976419C (en) 2020-01-21

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