US3028878A

US3028878A - Valve

Info

Publication number: US3028878A
Authority: US
Inventors: Paul J Natho
Original assignee: ACF Industries Inc
Current assignee: ANCHOR/DARLING VALVE COMPANY 919 CONESTOGA RD ROSEMONT PA 19010 A CORP OF; ACF Industries Inc
Priority date: 1957-09-12
Filing date: 1957-09-12
Publication date: 1962-04-10
Anticipated expiration: 1979-04-10

Description

April 10, 1962 J NATHO 3,028,878

VALVE Filed Sept. 12, 1957 7 a 4/ 1/. /Va /7 0 INVENTOR.

I; I ATfO/P/VEV United States Patent Jersey Filed Sept. 12, 1957, Ser. No. 683,614 6 Claims. (Cl. 137-556) This invention relates to a diaphragm operated motor valve and more particularly to a three-way motor valve which will divert flow to either of two outlet ports or stop flow completely.

Three-way diaphragm motor valves having three positions with the center position closed are designed for use in systems where it is required to divert'flow from one facility-to another or to stop flow completely. In the petroleum industry such valves are used in well test installations. In such installations flow from the well is periodically diverted from production facilities to test facilities and on-some occasions-when the well has flowed its allowable-flow is stopped completely. As a rule, there is always pressure in the production facility inasmuch as other wells will be feeding into such facility. If the well to which the motor valve is connected is producing less pressure than is in the production facility, and such well is switched to test, there will be a pressure differential between the outlet attached to the production facility and the interior of the valve. It is necessary to provide the valve with means to prevent this back pressure from unseatingthe supposedly closed valve and mixing flow from the production facility with the flow from the well. One of the main problems with prior art valves is that the valve will not seal against the differential back pressure. Prior art valves generally have a single stem extending from the diaphragm unit through the valve and two opposed collinear seat members are mounted thereon with a spring mechanism between them to return them to the closed position when a diaphragm is not pressurized. In utilizing such structure, it is virtually impossible to pressure balance the valve and therefore it will not seal against differential back pressure.

In the valve of the present invention, instead of having the opposed collinear valve members attached to a single stem there are two independent coaxial stems. The springs which return the valves to closed position are located in the diaphragm control unit rather than in the confined area between the opposed valve members. By utilizing such as structure, the effect of back pressure can be overcome so that it will not open the valve.

It is a primary object of the present invention to provide a three-way diaphragm motor valve with opposed collinear valve seats controlled by independent coaxial stems.

It is another object to provide an improved balanced three-position, center position closed, motor valve.

It is a further object to provide a three-position motor valve in which the effect of back pressure tending to open a valve member is overcome.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice. I

A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in accompanying drawing, forming a part of the specification wherein:

The FIGURE is a vertical view, part in section for clarity of illustration, through a three position diaphragm 2 motor valve embodying this invention. shown in the closed position. 7

Referring now to the drawing, the valve 10 is comprised of a housing 12 having a central open ended valve chamber 14 along the vertical axis and having an inlet port 16 and

outlet ports

18 and 28. The inlet port 16 and the outlet port 18 are opposed and one is on each side of the central valve chamber 14. The outlet port 20 forms the terminus of one end of the central chamber 14. All ports are in communication with the central chamber 14. The end of each port may be provided with threads to form half of a union thereby permitting the valve to be removed from a system Without further disturbing the piping.

Cylindrical sleeves

21, 22 and 23 are located in the chamber 14. The outer surfaces of the

cylindrical sleeves

22 and 23 are provided with circumferential grooves 24 having O-rings 26 which seal the cylindrical sleeves with the wall of the chamber 14. A barrier 28 is positioned between

cylindrical sleeves

22 and 23 and is also provided with an O-ring seal. The barrier 28 in effect divides the interior of the valve into two sections 30 and 32. Section 39 is provided with orifices 34 to permit fluid from the inlet port 16 to flow to outlet port 18,- and section 32 is provided with orifices 36 to permit fluid from the inlet port 16 to flow to the outlet port 20.

In section 30 between

sleeves

21 and 22 there is a valve seat 38 having an O-ring seal to seal it with the wall of the chamber 14. there is a valve seat 4t) similarly sealed to the chamber 14 with an O-ring. Opposed collinear valve members 42 and 44 register with valve seats 33 and 40 respegtively. Valve member 42 controls flow through section 30, and valve member 44 controls flow through section 32. These valve members when positioned against their respective valve seats will stop flow to the respective. outlet and when both valve members are closed flow will be completely shut off. In order to minimize the effect. of back pressure, the valve members 42 and 44 are provided with means to balance such back pressure. In the case of valve member 42, an orifice 46 is provided in the cylindrical sleeve 22. This permits pressure in the outlet line 18 to flow in back of the valve member 42 fully balancing any pressure from outlet 18 which may flow against the face of valve member 42. In effect it is slightly overbalanced since the area of the back of valve member 42 is greater than the exposed area of the face. Valve member 44 is provided with a passage 48 which permits pressure in outlet line 29 to flow to the base of valve member 44 to partially balance off any pressure that may act against the face of valve member 4-4. The valve member 44 can not be fully balanced in this manner due to stem 52 which is attached to valve member The valve is 44, but as will be explained subsequently effective balance is obtained by the proposed structure of the invention. Valve members 42 and 44 are controlled by

independent stems

50 and 52 respectively. The stem 52 is telescoped within stem 50. The coaxial stems 5t? and 52 extend through an O-ring sealed bonnet 54 which closes the upper end of the central chamber 14f By having utilized the

cylinder sleeves

21, 22 and 23 and O-ring seals, it

is possible to service the valve without removing it from the line. By removing bonnet 54, all members subject to wear can be easily removed and replaced.

A diaphragm control unit 56 provided with a centrally r located diaphragm 58 is attached to the bonnet 54. In

the center of the diaphragm there is a valve positioning member 59. A valve control member 60 for valve 42 is attached to the end of the stem 50. The valve control member 60 has a reduced portion which is telescoped in sliding relationship within the hub of the valve positioning member 59. The member 60 is provided with a Patented Apr. 10, 1962 In section 32 below sleeve 23 shoulder 61 which is contacted by the valve position member 59 on downward movement of the diaphragm 58 thereby opening the valve 42. A spring 64 is positioned between the bottom of member 60 and a central portion 66 of the bonnet 54. This spring will close the valve 42 as soon as pressure is released from top 02 the diaphragm 53. Stem 52 extends through stem 50 and the end thereof is provided with a valve control member 62. The member 62 is on top of the valve positioning member 59 upward movement of the diaphragm 58 and member 59 causes the control member 62 to move upward opening the valve 44. A spring 68 is positioned between the top of member 62 and the cap 70 of the diaphragm control unit. This spring will close valve 44 when pressure is released from the under side of the diaphragm S8.

Passages

72 and 74 permit pressure to be introduced into the diaphragm control unit to move the diaphragm either up or down to open either of the valves 42 or 44. The introduction and removal of pressure may be controlled by a four-way valve (not shown) as is well known in the art. Attached to the center of the diaphragm 53 there is an indicator rod 76 which will show the position of the diaphragm and thereof the position of the valves. The indicator rod 76 provides visual indication, also it may be attached to an electrical switch or switches (not shown) which will provide remote indication.

The valve is a fail close valve; that is, if for any reason pressure in the diaphragm control unit fails, any opened valve member will immediately be closed. This automatic action is obtained by the

springs

64 and 68. The fail close feature is required for many types of installations. If the valve members 42, 44 were slidably mounted on a single stern as is common in the prior art valves, it would be necessary to position the springs 64- and 68 in the confined area between the valve members 42 and 44. Balancing of such units is virtually impossible and therefore such valves have a tendency to leak when any back pressure is exerted upon them. Since the valves operate at high pressures, 2090 psi. or more, any slight difierence in area between the face and back of a valve member results in a substantial requirement of spring force which can not be accommodated in the small limited area between the opposed valve members.

By utilizing an independent stern for each valve mem her which coaxially extends into the diaphragm control unit, the

springs

64 and 68 can be removed from the confined area and placed in the diaphragm control unit where more space is available. Being so placed, there is a greater latitude in the selection of springs so that it is feasible to select springs of the proper magnitude which when taken in conjunction with the balancing effect obtained by feeding pressure to the back of the valve member will effectively balance the valve members so that it will not be unseated by back pressure thereby eliminating false opening and mixing.

As various changes may be made in the form, construc-' tion and arrangements of the parts herein without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. A diaphragm operated motor valve comprising a housing having a central open ended valve chamber extending along the vertical axis and an inlet port and two outlet ports, the inlet port and one outlet port being opposed, one on each side of the central chamber and the other outlet port forming the terminus of one end of the central chamber, all ports being in communication with said chamber, a cylindrical sleeve unit located in said chamber and provided with means to divide said chamber into two sections, one section directing fiow from the inlet port to one of the outlet ports and the other section directing fiow to the other outlet port, two valve seats spaced along the sleeve unit, one seat in one section and the one seat in the other section, opposed collinear valve members registering with said seats, said valve members and sleeve unit being provided with means whereby the valve members are at least partially balanced, an independent valve stem attached to each valve member, a bonnet closing the end of the chamber opposite an outlet port, a control unit provided with a diaphragm attached to the bonnet, the independent valve stems coaxially extending through the bonnet, the end of each stem provided with a valve control member, the valve control member of the outer stem located interiorly of the diaphragm and the valve control member of the inner stern located exteriorly of the diaphragm, valve positioning means in the center of the diaphragm which cooperate with the valve control members so that up ward movement of the diaphragm opens the valve controlled by the inner stem and downward movement of the diaphragm opens the valve controlled by the outer stem, a spring member on each side of the diaphragm, each spring cooperating with one of the independent stems to retain the respective valve closed when the dia' phragm is in the center position, and means to pressurize either side of the diaphragm.

2. The valve specified in claim 1 characterized in that an indicator position rod sensitive to diaphragm position extends through the diaphragm control unit to visually or remotely indicate position of the valve.

3. A diaphragm operated motor valve comprising a housing having a central open ended valve chamber extending along the vertical axis and an inlet port and two outlet ports, the inlet port and one outlet port being opposed, one on each side of the central chamber and the other outlet port forming the terminus of the lower end of the central chamber, all ports being in communication with said chamber, a cylindrical sleeve unit located in said chamber and provided with means to divide said chamber into two sections, one section provided with orifices to direct fiow from the inlet port to one of the outlet ports and the other section provided with orifices to direct flow to the other outlet port, two valve seats spaced along the sleeve unit, one seat in one section and the one seat in the other section, opposedd collinear valve members registering with said seats, one of said valve members and sleeve being provided with means whereby pressure from the outlet port is diverted to back of the valve member, an independent valve stem attached to each valve member, a bonnet closing the upper end of the chamber, a control unit provided with a diaphragm attached to the bonnet, the independent valve stems coaxially extending through the bonnet, the end of each stem provided with a valve control member, the valve control member of the outer stem located interiorly of the diaphragm and the valve control member of the inner stern located exteriorly of the diaphragm, valve positioning means in the center of the diaphragm which cooperate with the valve control members so that upward movement of the diaphragm opens the valve controlled by the inner stem and downward movement of the diaphragm opens the valve controlled by the outer stem, means to energize either side of the diaphragm, a spring member on each side of the diaphragm, each spring cooperating with one of the independent stems to retain the respective valves closed when the diaphagm is deenergized.

4. A three-way valve comprising a housing having an axially located open ended valve chamber, said housing also being provided with an inlet port and two outlet ports, one of said outlet ports forming a terminus of the open ended chamber and all ports being in communication with the chamber, two spaced valve seats located in the valve chamber, at least one of said valve seats being removable, two opposed collinear valve members, each valve member controlling fiow to one of the outlet ports. means to at least partially balance said valve members against back pressure on the face of said valve members, an independent valve stem attached to each valve memher, a bonnet closing the other end of the chamber, the independent valve stems extending coaxially through said bonnet, means to independently operate each valve member.

5. A diaphragm operated motor valve comprising a housing having a valve chamber along the vertical axis and having an inlet port on one side of said valve chamher and two outlet ports, one on the opposite side of said chamber and the other at the bottom of said chamber, the inlet port and outlet ports being in communication with said chamber, a cylindrical sleeve unit disposed in said chamber, said sleeve unit being provided with means to seal its outer surface, said sleeve unit also provided with means dividing the interior of the valve into two sections, one section diverting flow to one of said outlet ports and the other section diverting how to the other of said outlet ports, said means also isolating the outlet ports from direct communication with each other, two valve seats spaced along the axis of the sleeve unit, opposed collinear valve members registering with said seats, each seat and valve member stopping flow to one of the outlet ports, a valve stem attached to each valve member, said valve stems being coaxial and independent in operation, a bonnet closing the top end of the valve chamber, a diaphragm control unit attached to the bonnet, said coaxial valve stems extending through the bonnet and independently cooperating with the diaphragm control unit, a spring member on each side of the diaphragm control unit to return each valve member to a closed position when there is no pressure in the diaphragm control unit.

6. A diaphragm operated motor valve comprising a housing having a central open ended valve chamber extending along the vertical axis and an inlet port and two outlet ports, the inlet port and one outlet port being opposed, one on each side of the central chamber and the other outlet port forming the terminus of the lower end of the central chamber, all ports being in communication with said chamber, a cylindrical sleeve unit located in said chamber and provided with means to divide said chamber into two sections, one section provided with orifices to direct flow from the inlet port to one of the outlet po-rts and the other section provided with orifices to direct flow from the inlet port to the other outlet port, two valve seats spaced along the sleeve unit, one seat in one section and the one seat in the other section, opposed collinear valve members registering with said seats, the valve member controlling the outlet port forming the terminus of the central chamber of sufficient thickness to extend axially past the orifices from the inlet side and having means sealing it in the closed positon so that inlet pressure does not contact the rear face thereof, a passage in said valve member directing any fluid in the outlet passage to the rear side of said valve to at least partially balance said valve member and thereby, deter it from opening under back pressure, the other valve member being of sufficient thickness to extend axially past the orifices from the inlet side and having means sealing it in the closed position so that inlet pressure does not contact the rear face thereof, orifices in said cylindrical sleeve directing flow from the outlet port to the rear face of said valve member to at least partially balance said valve member and thereby deter it from opening under back pressure and means to independently operate either of said valve members.

References Cited in the file of this patent UNITED STATES PATENTS 564,249 Jones July 21, 1896 1,036,451 Casper Aug. 20, 1912 1,396,501 Brooks Nov. 8, 1921 2,141,018 Ring Dec. 20, 1938 2,479,454 Annin Aug. 16, 1949 2,633,868 Berhoudar Apr. 7, 1953 2,700,983 Bryant Feb. 1, 1955 2,783,020 Kleczek Feb. 26, 1957 2,845,085 Robbins July 29, 1958 2,89 36 e s g- 959