Valve-strainer housings and assemblies

An improved valve-strainer body or housing is disclosed wherein a single structure is adapted for use as both a valve housing for globe valves, gate valves, check valves and the like, and also utilized as a casing for a strainer. The housing is sized such that the single housing may be utilized in differing sized pipeline systems from approximately 1/4 inch IPS to 1 inch IPS. The invention also discloses superior means of using the valve body casing in connection with not only threaded pipe systems, but also brazed pipe systems and welded pipe systems. Finally, improvements in the valve assembly structure is also disclosed.

BACKGROUND OF THE INVENTION 
The invention relates generally to improvements in valve-strainer 
assemblies and more particularly, to an improved valve-strainer body or 
casing wherein a single structure is adaptable for use both as a valve 
housing and a strainer housing in varying sized and varying type pipe 
systems. Additionally, the invention relates to specific improvements in a 
valve assembly inserted in the housing, and a strainer which is utilizable 
in connection with the same housing. 
Heretofore known valve assemblies utilizing structures which Applicant has 
found to be most relevant to the disclosure of the present invention are 
found in the following U.S. Pat. Nos. 3,552,714 issued to Charles 
Manville; 3,658,291 issued to H. Meges; 3,700,206 issued to E. Jones; 
4,121,619 issued to R. Pauliukonis and 4,249,717 issued to W. Thompson. A 
heretofore known filter element which Applicant has found as being closest 
to the strainer element disclosed herein is found in U.S. Pat. No. 
4,164,048, issued to J. Kampfer, et al. 
While the valve art is a mature one, Applicant has found that the 
improvements disclosed herein provide better solution foran age-old 
problem of leakage relating to such valves in use over a period of time, 
than found in valves of known construction. Additionally, the utilization 
of the same housing in different types of valves of differing sizes and 
also in a strainer provides heretofore unknown efficiences of construction 
for such devices. 
SUMMARY OF THE INVENTION 
Invention is directed to valve-strainer assemblies, and to improvements 
thereof, wherein a valve assembly includes a valve housing, a valve stem 
mountable for reciprocating movement in the housing, and means for forming 
a sealing relation between the valve stem and a valve stem bore. The bore 
and the valve stem include complimentary threaded surfaces along a portion 
of their lengths, and the bore includes an enlarged cylindrical area 
outwardly adjacent the threads. Packing material is positioned in at least 
a portion of that enlarged area, and a packing gland nut is 
threadedlyreceived at the top of the cylindrical area for applying 
pressure on the packing material thereunder. An improvement includes a 
second cylindrical area of lesser diameter than the enlarged cylindrical 
area and positioned between the complimentary threaded surfaces and the 
enlarged cylindrical area to define an annular land therebetween which is 
perpendicular to the valve stem. An annular sealing ring is positioned in 
the second cylindrical area for providing a sealing engagement between the 
stem and the bore and a rigid annular washer is mounted on the land for 
separating the annular sealing ring from the packing material. 
The invention is further directed in the valve assembly to a cylindrical 
valve disc including an annular recess extending radially inwardly 
adjacent a bottom of the disc for receiving and retaining an annular 
sealing seat member thereon. The improvement includes the recess being 
generally rectangular in radial cross section and having a radially 
extending lip at a bottom end thereof for retaining an annular sealing 
seat thereon once same is stretched thereover. At least one of the 
remaining surfaces of the annular recess includes an annular discontinuity 
of a size sufficient to create a sealing engagement by deforming an 
adjacent surface of the annular sealing seat which is contiguous 
therewith. 
Additionally, the invention is directed in the valve assembly to 
improvements in the mounting between a generally cylindrical valve disc 
and a valve stem or rod having a generally cylindrical body end. The valve 
disc includes a valve stem receiving bore therein of a diameter larger 
than a diameter of the stem bottom end for fitting therein. The valve disc 
includes a stem receiving bore and a first annular groove in the stem 
receiving bore and the second annular groove adjacent to the bottom end of 
the valve stem, with both grooves positioned for combined formation of a 
hollow annular passageway when the valve stem is positioned in the valve 
receiving bore. A plurality of spherical members are sized to fit in the 
combined passageway and retain the stem in the bore. Access bore means on 
the valve disc between an outside surface thereof and the combined 
passageway providing ingress and egress of the spherical members to the 
hollow annular passageway. An annular zone of shallow relief relative the 
second annular groove and positioned immediately inwardly there adjacent 
on the valve stem provides an area into which metal deformation of the 
valve stem may occur without forming an interference fit between the valve 
stem and the stem bore. 
The invention is further directed in the assembly to a housing having an 
inlet passageway, an outlet passageway, and a central body portion 
therebetween. The central body portion is bifurcated by a curved dividing 
wall having a central aperture therethrough, The central body portion 
further includes an annular flange extending from an external portion of 
same wherein the annular flange is coaxial with the aperature through the 
dividing wall. An improvement resides in the housing being adaptable for 
use both as a globe, check, or other valve housing, and also as a strainer 
housing by the addition of a cover means which is threadedly retained on 
the annular flange, and a generally cylindrical strainer assembly which is 
received at one end in said dividing aperature and biased thereagainst by 
biasing means on the bottom of the strainer which contact the inner end of 
the cover. 
The invention is further directed to an improved strainer or filter element 
including a generally cylindrical foraminous body, an annular top 
framework adapted for being retained on the dividing wall circular 
aperature, and a biasing spring between the bottom of the filter element 
and the closure cover. The filter element includes an annular opening 
engaging the annular top framework, and a closed body and including a 
plurality of doublefolded adjacent sidewall pleats, each joined along a 
double-folded end and all joined together centrally of the end of the 
element to define radially extending pleats. 
The invention is further directed to a cover made of resilient material 
which is adapted for fitting over the valve stem and covering the top 
exposed portion of a valve stem housing to protect external threads on the 
housing, and to provide a thermo barrier to prevent frost buildup on those 
threads during use of the valve in a refrigerant system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
Referring to FIG. 1, a first embodiment of the present invention is found 
in a globe valve 10, constructed in accordance with the present invention, 
which includes a valve body housing 11, consisting of inlet and outlet 
passageway flanges 12, 13, respectively, with each flange having a 
threaded passageway 12a, 13a, respectively, therethrough, a central 
chamber 14 which is bifurcated by a curved dividing wall 15 having a 
vertically axially disposed aperture-valve seat 16 therethrough, and a 
generally cylindrical annular flange 17 which is axially aligned with the 
valve seat aperture 16. In this embodiment, an annular valve stem housing 
assembly 20 is mounted mainly inside the annular flange 17 and includes an 
annular stem housing 21, a valve stem 22 which is threadedly mounted in 
the housing 21, and a valve disc assembly 23 which is loosely retained in 
a self-centering manner on the inward end of valve stem 22 so as to 
sealingly engage the valve seat 16 when the stem is threaded fully into 
the housing 21. Additionally, valve stem assembly 20 includes means for 
manual use opening and closing of the valve, in this embodiment, a 
handwheel 24 which is releasably retained on the outer distal end of valve 
stem 22. A valve packing assembly, generally indicated at 25, prevents the 
escape of fluids from between the valve stem and valve stem housing in a 
superior manner. A sealing means, generally indicated at 26, is positioned 
between the valve stem housing 21 and the annular housing flange 17 of the 
valve body 11 to prevent fluid escape through that juncture. Finally, a 
thermal barrier and thread cover 27 is utilized both to protect the 
exposed outer threads on stem housing 21 and to provide a barrier which 
prevents frost buildup on the threads when the valve is used in a 
refrigerant system. It should be noted that in some valves, this annular 
flange serves the same function by itself as the flange and valve stem 
housing perform in the arrangement shown. 
Referring to FIGS. 2 and 2(a), the improvements of Applicant's invention in 
connection with the valve stem assembly and valve stem housing are shown 
in greater detail. Starting with the bottom of the valve stem assembly, 
the valve disc 23 is circular in outline and includes an annular recess 30 
adjacent to the bottom end thereof into which an annular valve seat 
sealing member 31, in this embodiment preferably made of 
polytetrafluroethylene or lead, is retained by being stretched over the 
distal edge or lip of the recess and retained thereover by a coiled 
retaining clip 32. The sealing member 31 has a frusto-conical face which 
is adapted for matingly sealingly engaging a similar frusto-conical face 
on the valve seat 16 positioned through dividing wall 15 in the central 
chamber of the valve body housing 11. While the soft material of valve 
sealing member 31 is adapted to provide a sealing engagement with the 
valve seat 16, in one aspect of the invention additional potential leakage 
around the backside of the sealing member 31 is prevented by means of a 
secondary recess 33, in this embodiment approximately 1/64 inch in height, 
is cut from the upper wall of recess 30 and provides an annular 
deformation in this form of a right angled edge between recesses 30 and 33 
into which the sealing member creeps or is deformed. 
In another aspect of the present invention, the self-centering mounting of 
the disc 23 on the lower end of the valve stem 23 is accomplished by a 
plurality of ball bearings 34-34 which are rollably fitted into an annular 
race defined by a first annular groove 35 on the interior of cylindrical 
recess 36 of disc 23 which is positioned to align with a second annular 
groove 37 adjacent the distal end of valve stem 22. When the disc is 
positioned on the distal end of the valve stem 22, the ball bearins 34-34 
may be fitted into an access bore 40 in the disc and the balls are dropped 
into the combined race 35-37. A coiled retainer 41 fits in an external 
groove 42 of disc 23 and has a fingerlike projection which extends into 
the bore 40 to prevent escape of the ball bearings 34-34 unless removal is 
desired. Liberal tolerances between the ball bearings 34, annular race 
portions 35-37, and the distal end of the valve stem 22 and recess 36 
provide for relative movement between the valve stem and the disc within 
limits thus allowing automatic centering of the valve disc when it is 
positioned on the valve seat 16. As shown most clearly in FIG. 2(a), in 
one aspect of the present invention the upper edge of the grooved race 
portion 37 in valve stem 22 is relieved as shown at 37(a) in FIG. 2(a) so 
that any force on the upper edge of groove 37 caused by repeated closing 
of the valve does not deform that upper edge outwardly to cause 
interference with recess 36 and hinder removal of the valve disc from the 
valve stem. 
Moving up of the valve stem 22, a raised flange 42 acts as a stop to align 
the valve disc onto the valve stem for inserting ball bearings 34-34 
therein, and the opposing side of the flange 42 includes a frusto-conical 
wall section 43 which, when the stem is in the uppermost position, engages 
an annular right angle shoulder 44, at the base of stem bore 45 in stem 
housing 21. Engagement of frusto-conical surface 43 with shoulder 44 
provides an annular line type seal between the valve 22 and the valve stem 
housing 21 when the stem is fully retracted position (the valve is fully 
open). 
Moving up the valve stem 22 again, a threaded portion 46 of valve stem 22 
threadedly engages the mating thread 47 in the stem bore 45, thus moving 
the valve disc 23 in and out of engagement with the valVe seat 16 in a 
precise fluid-flow controlling manner. Above the threaded portion 46, the 
remainder of valve stem 22, except for the handwheel mounting end, is a 
smooth round cylindrical structure or rod which is adapted to sealingly 
engage the packing assembly 25 mounted in a widened portion of the stem 
housing bore 45. The bottommost portion of the widened packing segment of 
the housing stem bore 45 includes an annular O-ring holding recess 50 
positioned immediately above threads 47. Above recess 50 is a larger 
diameter packing retaining recess 51 with the juncture therebetween 
defining an annular landing 52. From the top of annular packing recess 51 
to the outside of the housing stem bore is a threaded portion 53 which is 
adapted for threadedly receiving a packing gland nut 54 therein. 
Another important aspect of the present invention resides in the dual 
series sealing structure positioned between the stem threads 46 and the 
packing nut 54. Immediately adjacent the threaded portion 46 in the O-ring 
recess 50, is positioned an O-ring 55 which is adapted for sealing surface 
contact between the valve stem 22 and the valve stem housing 21. 
Additionally, an annular valve packing 56 is positioned around valve stem 
22 between the packing gland nut 54 and a rigid washer 57 which is 
retained on land flange 52 in order to separate the O-ring 55 from the 
packing 56 and maintain the packing in an orderly shape. In the present 
embodiment of the invention, packing gland nut 54 is not substantially 
tightened when the refrigerant valve is newly placed in service. The 
O-ring 55 provides the primary sealing means between the valve stem 22 and 
the valve stem housing 21. As the valve stem is used or maintained in 
service for longer periods of time, should some leakage eventually occur 
around O-ring 55, the packing gland nut 54 may then be tightened such that 
the packing 56 provides an additional sealing capability between the valve 
stem 22 and the stem housing 21. Further, the provision of graphite 
lubricant in packing 56 acts to lubricate and strengthen the seal between 
the O-ring 55, stem 22, and housing 21 whenever the valve stem 22 is moved 
downwardly axially in stem bore 45. 
As shown most clearly in FIG. 2, a thermal cover 27, (in this embodiment 
preferably made of plastic material) includes an upper flange portion 27a 
having an aperture 27b centrally therein which is adapted to engage the 
outer threads of packing gland nut 54 and an annular cylindrical flange 
27c extending downwardly from the periphery of upper flange portion 27a 
engages an upper threaded portion of the valve stem housing 21. This 
plastic cover 27 protects the stem housing threads from abuse, both when 
the valve is in storage or being shipped, and also when the valve is in 
service, and provides a cover for those threads to prevent frost or other 
moisture buildup thereon which may lead to rust and other deleterious 
effects on those threads. 
In order to effectively seal the annular juncture between the valve stem 
housing 21 and the annular flange 17 in the valve body, another O-ring 60 
is positioned in an annular groove 61 on the outside of valve stem housing 
21 such that sealing engagement of the O-ring between the inside of the 
annular flange 17 and the outside of the valve stem housing 21 is 
accomplished when the housing is threadedly inserted in the flange. 
Additionally, an annular line sealing engagement is accomplished between 
an annular right angle shoulder 62 on the outside of the valve stem 
housing 21 and a frusto-conical annular surface 63 adjacent the distal end 
of flange 17 similar to the sealing engagement between valve stem 
frusto-conical surface 43 and right angle shoulder 44 discussed 
previously. 
Referring to FIGS. 3(a), 3(b) and 3(c), modifications of the outlet 
passageway of a valve housing similar to housing 11 in the first 
embodiment are shown generally at 70, 71 and 72, respectively. Valve 
housing outlet passageway 70 has been modified by the rotating insertion 
of a threaded tubular member 73 which has been welded at the juncture of 
the outlet flange face 74 and tube 73 by annular weld 75. The tubular 
segment 73 incorporates one aspect of the present invention by having 
formed thereon a relief area 76 between the tubular member threads 77 and 
the remainder of the tube. This relief area eliminates the existence of 
threads axially outwardly of face 74, provides a uniform juncture between 
tube 73 and face 74, and allows the contact structure adjacent welding 
bead 75 to be substantially uniform in cross-section thus providing a 
better seal between the tube 73 and face 74. When threads stick out 
axially beyond face 74, the welding bead may tend to blow away some of the 
metal in the threads or create other discontinuities which hinder 
obtaining a complete sealing weld between the face 74 and tube 73. Such 
construction is utilized when welded steel or other tube construction is 
found in a refrigeration system in which the valve is positioned. In a 
preferred embodiment, flange face 74 and the outside of tube 73 wherein 
bead 75 will be positioned are machine faced to provide greater uniformity 
in their structure. Referring to FIG. 3(b), the valve body housing 80 is 
shown with a threaded exit passageway 81 therethrough which is smaller in 
diameter than the threaded exit passageway 13a shown in FIG. 1, so as to 
allow a smaller diameter threaded pipe 82 to be matingly engaged therein. 
As can be seen by FIG. 3(b)the valve body housing of the present invention 
may be modified such that one size casting may be utilized for several 
differing pipe-size installations. 
In FIG. 3(c), a third modification 72 the valve passageway includes a 
housing 80 having a large diameter machined cylindrical flange 81 
including an internal annular stop portion 82 which is formed therein as a 
stop for a copper tube 83 which is matingly engageable therein for brazing 
thereto. The machining of annular flange 81 and stop 82 onto the same base 
casting as is found in valve body 11 provides an additional use for the 
same casting and thus cuts manufacturing costs for differing type valve 
body housings, all within the scope of the present invention. 
Thus, the valve housing aspect of the present invention has been shown as 
utilized in a globe-type valve, which is one of its many adaptational 
uses. Hereinafter, the valve body housings shown are substantially similar 
to housing 11, although the finish structure shape (machining) may differ 
for varying applications thereof. However, the adaptational aspect of the 
housing in the present invention is easily recognized when viewing the 
drawings disclosed and described hereafter. 
Referring to FIGS. 4, 5 and 6, and in-line type strainer, generally 
indicated at 90, includes a housing 91 having an inlet side 92 with an 
inlet passageway 93 therethrough; an outlet side 94 with an outlet 
passageway 95 therethrough; and a central portion 96therebetween which is 
bifurcated by a curved dividing wall 97 having a central aperture 98 
therethrough. An annular generally cylindrical flange 100 extends from the 
central body portion 96 in a direction co-axial with the axis of aperture 
98. The outside of annular flange 100 is threaded at 101 for matingly 
receiving an elongate cap 102 thereover. In one aspect of the present 
invention a strainer or filter element 103 is positioned with its outlet 
end through aperture 98 and is retained against movement at the opposite 
end of the strainer by cap 102. 
Filter element 103, which is constructed in accordance with the present 
invention, is preferably made of stainless steel, bronze, or plastic 
screen material which is bent to form a hollow generally cylindrical 
foraminous body 104 at its top end while being deformed inwardly at a 
plurality of positions (in this embodiment 4 positions at 90.degree. 
intervals) along a substantial portion of its length to form a generally 
cross-shape section structure when viewed as shown most clearly in FIG. 6. 
At the bottom of strainer body 104, the severity of the deformations 
increase to the point where the screen side segments lose all internal 
spacial dimension as adjacent contiguous side segments are pinched or 
pleated together at bottom end 105. A coil spring 106 is affixed to the 
bottom end 105 of strainer element 103 to contact the bottom of cover 102 
and bias the filter element against the dividing wall aperture 98. At 
spaced positions along the length of filter element 103, annular 
strengthening ribs 107, 108 and upper annular mounting member 110 
strengthen the filter element and maintain same in mounted position. In 
the preferred embodiment, a permanent magnet 111 is positioned within the 
coil spring 106 to attract any loose metallic particles in the inlet 
portion of the strainer. 
The strainer structure shown most clearly in cross-section FIG. 6 provides 
additional space between the outside surface of the strainer 103 and the 
inner surface of the annular flange 100 and cap 102. This additional space 
tends not only to equalize the flow space inside and outside the filter, 
but also increases the amount of space which may be utilized for 
deposition of particulate matter which cannot flow through the foraminous 
filter body 104. As such, the filter element 103, constructed in 
accordance with the present invention, provides a superior construction 
over heretofore known filter elements, while the strainer housing 91 shows 
its adaptability between its uses as a globe valve housing and as a 
strainer housing. 
Referring to FIG. 7, an additional modification of the present invention is 
shown as a check valve assembly 120 which utilizes the same housing 121 as 
shown at 11 in FIGS. 1 and 2. Housing 121 includes an inlet flange 122 
having an inlet passageway 123 therethrough, an outlet flange 124 having 
an outlet passageway 125 therethrough, and a central portion 126 having a 
curved dividing wall 127 with an annular valve seat aperture 130 
positioned therethrough, similarly as is shown in globe valve housing 11 
in FIG. 2. Likewise, check valve housing 121 includes an annular flange 
131 extending axially from the central body portion 126 co-axially with 
the valve seat 130 in dividing wall 127. A check valve mounting 132 is 
retained on the annular flange 131 by mating threaded portions 133, 134 
and is sealed therewith by means of an O-ring 135 mounted in an annular 
groove 136 in mounting 132. 
Similarly to the valve stem mounting housing 21 shown as in FIG. 2, an 
additional annular line sealing engagement is formed upwardly and 
outwardly of O-ring 135 by means of a frusto-conical surface 137 adjacent 
the outward distal end of flange 131 which sealingly engages an annular 
right angle shoulder 140 formed on the outer portion of check valve 
mounting 132 in a manner similar to that shown at sealing shoulder 62 and 
surface 63 in the first embodiment in FIG. 2. A central cylindrical recess 
141 in mounting 132 provides a guide for axial reciprocal movement of a 
check-valve pistion 142 therein. At the bottom distal end 143 of piston 
142, a valve disc 144, which is identical to valve disc 23 in the first 
embodiment, is mounted in a manner identical to that shown in FIG. 2. 
Piston 142 and disc 144 attached thereto are biased against valve seat 130 
by means of a coil spring 145 mounted between the piston 142 and check 
valve mounting 132. The pressure at which check valVe 120 opens is 
dependent upon the spring rate of spring 145. 
Thus, the various aspects of the present invention have been shown to 
provide a multitude of structures which are interchangeable between globe 
valves, check valves, and strainers, all within the scope of the present 
invention. The structural advantages of the invention which are unrelated 
to the valve disc assembly 23 are also adaptable for use on gate valves. 
Novel structures and functional aspects of the invention disclosed herein 
provide increased efficiencies of manufacture and increased sealing 
capability for valves and strainers generally, and particularly for those 
used in refrigerant systems. 
While three embodiments, and several modifications, of the present 
invention have been shown and described, it will be obvious to those 
skilled in the art that changes and modifications may be made without 
departing from the invention in its broader aspects. Therefore, the aim in 
the appended claims to cover all such changes and modifications as may 
fall within the true spirit and scope of the present invention.