U.S. patent number 3,625,390 [Application Number 04/704,368] was granted by the patent office on 1971-12-07 for sight glass assembly.
Invention is credited to Charles E. Meginnis.
United States Patent |
3,625,390 |
Meginnis |
December 7, 1971 |
SIGHT GLASS ASSEMBLY
Abstract
A sight glass assembly comprising housing means having an
opening therethrough, a lens mounted in the opening, the opening
having an inclined wall, resilient packing means interposed between
the lens and the inclined wall of the opening, a faceplate disposed
about the lower periphery of the lens engageable with the packing
member and means for securing the faceplate to the housing means to
apply a force on the packing means directed against the inclined
wall of the opening in the housing means whereby the packing means
is forced toward the lens to provide a compressive force about the
periphery thereof.
Inventors: |
Meginnis; Charles E.
(Charleston, WV) |
Family
ID: |
24829182 |
Appl.
No.: |
04/704,368 |
Filed: |
February 9, 1968 |
Current U.S.
Class: |
220/328; 73/334;
220/377; 220/663; 359/894 |
Current CPC
Class: |
B01J
3/004 (20130101); G02B 7/007 (20130101) |
Current International
Class: |
B01J
3/00 (20060101); B65d 053/06 () |
Field of
Search: |
;220/46,81,82,46R,81R,82R ;73/334,330,331 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Lowrance; George E.
Claims
I claim:
1. A sight glass assembly comprising housing means having an outer
side, an inner side mountable on a vessel wall having an opening
therein and an opening therethrough registrable with the opening in
said wall when said housing means is mounted on said wall, a lens
having outer and inner sides mounted in said opening of said
housing means, said opening in said housing means having a
peripheral wall inclined away from and in opposed relation to the
periphery of said lens, packing means consisting of a resilient
material interposed between the periphery of said lens and the
inclined wall of the opening in said housing means, a faceplate
disposed about the inner periphery of said lens engaging said
packing means and means for securing said faceplate to the inner
side of said housing means to apply a force on said packing means
directed against said inclined wall whereby the packing means is
forced toward said lens to provide a compressive force about the
periphery thereof.
2. A sight glass assembly according to claim 1, wherein the lens is
circular, the inclined wall is frustoconical and the faceplate is
annular.
3. A sight glass assembly comprising housing means having an
opening therethrough, a lens mounted in said opening, said opening
having a peripheral wall inclined away from and in opposed relation
to the periphery of said lens, packing means consisting of a
resilient material interposed between the periphery of said lens of
the inclined wall of the opening in said housing means, a faceplate
disposed about a periphery of said lens engaging said packing
means, said packing means being adhesively secured to said lens and
said faceplate, and means for securing said faceplate to said
housing means to apply a force on said packing means directed
against said inclined wall whereby the packing means is forced
toward said lens to provide a compressive force about the periphery
thereof.
4. A sight glass assembly according to claim 3 wherein the lens is
circular, the inclined wall is frustoconical and the faceplate is
annular.
5. A sight glass assembly comprising housing means having an
opening therethrough, a circular lens mounted in said opening, said
opening having a peripheral, frustoconical wall inclined away from
and in opposed relation to the periphery of said lens, packing
means consisting of a resilient material interposed between the
periphery of said lens and the inclined wall of the opening in said
housing means, an annular faceplate disposed about the periphery of
said lens engaging said packing means, said packing means having an
annular flange portion interposed between said faceplate and said
housing means, and means for securing said faceplate to said
housing means to apply a force on said packing means directed
against said inclined wall whereby the packing means is forced
toward said lens to provide a compressive force about the periphery
thereof.
6. A sight glass assembly according to claim 5 wherein said packing
means is adhesively secured to said lens and said faceplate.
7. A sight glass assembly comprising housing means having an
opening therethrough, a circular lens mounted in said opening, said
opening having a peripheral frustoconical wall inclined away from
and in an opposed relation to the periphery of said lens, packing
means consisting of resilient materials interposed between the
periphery of said lens and the inclined wall of the opening in said
housing means, an annular faceplate disposed about the periphery of
said lens engaging said packing means, annular cushioned gaskets
interposed between the lens and the housing means and the lens and
the faceplate, and means for securing said faceplate to said
housing means to apply a force on said packing means directed
against said inclined wall whereby the packing means is forced
toward said lens to provide a compressive force about the periphery
thereof.
8. A sight glass assembly according to claim 7 wherein said packing
means is adhesively secured to said lens and said faceplate.
9. A sight glass assembly comprising housing means having an
opening therethrough, a circular lens mounted in said opening, said
opening having a peripheral, frustoconical wall inclined away from
and in opposed relation to the periphery of said lens, packing
means consisting of a resilient material interposed between the
periphery of said lens and the inclined wall of the opening in said
housing means, an annular faceplate disposed about the lower
periphery of said lens engaging said packing means, said housing
structure having an annular beveled surface opposed to said
faceplate, said packing means including an annular flange portion
interposed between said faceplate and the annular beveled portion
of said housing means, annular cushioning gaskets interposed
between said lens and said housing means, and said lens and said
annular faceplate, and means for securing said faceplate to said
housing means to apply a force on said packing means directed
against said inclined wall whereby the packing means is forced
toward said lens to provide a compressive force about the periphery
thereof.
10. A sight glass assembly according to claim 9 wherein said
packing means is adhesively secured to said lens.
11. A sight glass assembly comprising housing means having an
opening therethrough, a lens mounted in said opening, said opening
having a peripheral wall inclined away from and in opposed relation
to the periphery of said lens, packing means consisting of a
resilient material disposed in said opening between the periphery
of said lens and the inclined wall of the opening in said housing
means, liner means consisting of a corrosive resistant material
interposed between the lens and said packing means including an
outwardly projecting flange portion, a faceplate disposed about the
lower periphery of said lens engaging said flange portion of said
liner means, means for securing said faceplate to said housing
means to apply a force through said flange portion of said liner
means directed against said inclined wall of said opening whereby
the packing means is forced toward the lens to provide a
compressive force about the periphery of the lens and packing means
disposed between the periphery of said lens and said faceplate.
12. A sight glass assembly according to claim 11, wherein the lens
is circular, the inclined wall is frustoconical, the liner means is
cylindrical having an annular flange portion and the faceplate is
annular.
13. A sight glass assembly according to claim 12, wherein the
packing means is provided with an annular flange portion interposed
between said flange portion of the liner means and said housing
means.
14. A sight glass assembly according to claim 12, wherein annular
cushioning gaskets are interposed between the lens and the housing
means and the lens and the faceplate.
15. A sight glass assembly accordingly to claim 11, wherein the
lens is circular, the opening wall is frustoconical, the liner
means is cylindrical having an annular flange portion, the
faceplate is annular, the housing structure is provided with an
annular beveled surface opposed to the annular flange portion of
the liner means, the packing means includes an annular flange
portion interposed between the annular portion of the liner means
and the annular beveled surface of the housing means and annular
cushioning gaskets are provided between the lens and the housing
means and the lens and the annular faceplate.
16. A lens unit adapted to be mounted in a sight glass assembly
including housing means having an opening therethrough, the opening
having an inclined wall, comprising a lens mountable in said
opening so that the periphery thereof will oppose said inclined
wall of said opening, a packing means consisting of a resilient
material adhesively secured to the periphery of said lens whereby
the packing means is interposed between the periphery of the lens
and the inclined wall of said opening when said lens is mounted
within said opening, a faceplate disposed about the lower periphery
of said lens adhesively secured to said packing means and means for
securing said faceplate to said housing means when said lens is
mounted in said opening to apply a force on said packing means
directed against said inclined wall whereby the packing means is
forced toward the lens to provide a compressive radial force about
the periphery of said lens.
17. A lens unit adapted to be mounted in a sight glass assembly
including housing means having an opening therethrough, the opening
having an inclined wall, comprising a faceplate having an opening
therein, a lens secured to said faceplate across the opening
thereof, liner means consisting of a corrosive resistant material
disposed about the periphery of said lens including an outwardly
projecting portion engageable with said faceplate, packing means
consisting of a resilient material disposed on said liner means
engageable with said inclined wall of the opening in said housing
means when said lens is inserted in the opening of said housing
means and means for securing said faceplate to said housing means
to apply a force through said flange portion of said liner means
directed against said inclined wall of the opening of said housing
means whereby the packing means is forced toward the lens to
provide a compressive force about the periphery of the lens.
Description
This invention relates to a sight glass assembly, and more
particularly to a sight glass assembly suitable for use with
high-pressure vessels.
In the prior art there has been developed a type of sight glass
assembly which generally includes a housing member having an
opening therethrough, which is adapted to be mounted across an
opening in a pressure vessel, a lens mounted in the opening of the
housing member and a packing member mounted in the opening in the
housing member between the wall of the opening in the housing
member and the periphery of the lens. In this general type of sight
glass assembly it has been found that the principal source of
failure resides in leakage of the medium in the pressure vessel
through the assembly between the packing member and the lens. It,
therefore, has been found desirable in the art to provide a sight
glass assembly, of the general type described, which would
materially reduce and preferably eliminate the above-mentioned
source of failure.
Accordingly, it is the principal object of the present invention to
provide an improved sight glass assembly.
Another object of the invention is to provide an improved sight
glass assembly of the type having a lens mounted in a metal housing
structure, wherein effective sealing is provided between the lens
and the housing structure.
A further object of this invention is to provide an improved sight
glass assembly mountable on a vessel containing a fluid under
pressure, having primary and secondary sealing means to prevent
leakage of the fluid through the assembly.
A still further object of this invention is to provide a novel
sight glass assembly suitable for use with high-pressure vessels
wherein the lens thereof is maintained in radial compression, thus
preventing blowout of the lens under normal operating
conditions.
Another object of this invention is to provide an improved sight
glass assembly for vessels containing corrosive mediums, wherein
the sealing means of the assembly is protected from the corrosive
medium.
A further object of the present invention is to provide a novel
lens unit for a sight glass assembly.
A still further object of the present invention is to provide an
improved sight glass assembly for pressure vessels, which is
comparatively simple in construction, relatively easy to assemble
and disassemble and inexpensive to manufacture.
Other objects of the present invention will become more apparent to
those persons skilled in the art, from the following description
when taken in conjunction with the accompanying drawings,
wherein:
FIG. 1 is a top plan view of an embodiment of the invention;
FIG. 2 is an exploded perspective view of the embodiment
illustrated in FIG. 1;
FIG. 3 is an enlarged cross-sectional view taken along line 3--3 in
FIG. 1;
FIG. 4 is an exploded view of another embodiment of the invention
illustrated in vertical cross section; and
FIG. 5 is an enlarged assembled view of the embodiment illustrated
in FIG. 4, illustrating the components in vertical cross
section.
Briefly described, the present invention relates to a sight glass
assembly generally comprising a housing means having an opening
therethrough, a lens mounted in the opening, the opening having a
peripheral wall inclined away from and in opposed relation to the
periphery of the lens, packing means consisting of a resilient
material interposed between the periphery of the lens and the
inclined wall of the opening in the housing means, a faceplate
disposed about the lower periphery of the lens engaging the packing
means, and means for securing the faceplate to the housing means to
apply a force on the packing means directed against the inclined
wall of the opening in the housing means, whereby the packing means
is forced toward the lens to provide a compressive force about the
periphery of the lens and opposing the force of the pressure within
the vessel on which the assembly is adapted to be mounted.
Preferably, the packing means is adhesively secured to the lens and
the faceplate.
According to a more specific embodiment of the invention, there is
provided a sight glass assembly comprising a housing means having a
circular opening therethrough. Mounted in the opening is a circular
lens. The opening in the housing member is provided with a
peripheral wall which is substantially frustoconical in shape and
disposed in opposed relation to the periphery of the lens. Packing
means consisting of a resilient material, is interposed between the
periphery of the lens and the frustoconically shaped wall of the
opening. An annular faceplate is mounted about the lower periphery
of the lens engaging the packing means, which is secured to the
housing means about its circumference to apply a force on the
packing means directed against the inclined wall of the opening in
the housing means, whereby the packing means is forced toward the
lens to provide a compressive radial component of force about the
periphery of the lens and an axial component of force opposing the
force developed by the pressure in the vessel. Preferably, the
housing structure is provided with an annular beveled surface
adjacent the opening therein and opposed to the faceplate, which is
adapted to receive therebetween an annular flange portion of the
packing means, which is compressed when the faceplate is secured to
the housing means. In addition, the packing means is adhesively
secured to the lens and the faceplate.
Referring to FIGS. 1 through 3 of the drawings, there is
illustrated an embodiment of the invention. FIG. 1 illustrates a
sight glass assembly 10, which is adapted to be rigidly secured to
a vessel or container 11 containing, perhaps, a fluid under
pressure. As best shown in FIG. 2, the assembly includes a housing
member 12, a lens 13, upper and lower cushioning gaskets 14 and 15
(not shown in FIG. 2), a packing member 16 and a faceplate 17. The
entire assembly is adapted to be mounted on the pressure vessel 11
across a circular opening 18, as illustrated in FIG. 3.
The housing member 12 is substantially annular, having parallel
upper and lower annular surfaces 19 and 20. The lower surface 20 is
adapted to be disposed adjacent the wall of the pressure vessel.
The housing structure is provided with a plurality of
circumferentially spaced openings 21 for receiving bolts 22
therethrough, for rigidly securing the sight glass assembly to the
wall of the pressure vessel.
Leakage between the wall of the pressure vessel and the sight glass
assembly is prevented by means of an annular sealing gasket 23
disposed between the bottom surface of faceplate 17 and an annular
recess 32 formed in the wall of the pressure vessel.
The housing structure also is provided with a circular opening 24
therein. The upper end of the opening 24 is beveled as at 25, and
the opening is enlarged, as at 26, to provide an annular shoulder
27. Below the enlarged opening 27, the opening is enlarged further,
and is provided with a frustoconically shaped wall 28. The lower
end of the opening also is provided with an annular beveled surface
29, which is curved upwardly at its inner end to merge into the
frustoconically shaped wall 28. Seated on the annular shoulder 28
is the upper annular gasket 14 which is engaged by the lens 13. The
lens 13 is cylindrical in shape and is provided with a cylindrical
wall 30, which is spaced from the frustoconically shaped wall 29 of
the opening in the housing member. Interposed between the wall 28
and the cylindrical surface 30 of the lens is the packing member
16. The packing member is formed from a resilient material which is
premolded. The packing member includes an integral annular flange
portion 31 at its lower end, which engages the annular beveled
surface 29 of the housing member.
Mounted on the packing member 16, including the annular flange
portion 31 thereof, is the faceplate 17. The faceplate 17 is
annular, having an outside diameter substantially equal to the
outside diameter of the beveled surface 29 of the housing member
and an inside diameter slightly less than the diameter of lens 13.
The upper inner portion of the faceplate 17 is recessed to receive
the lower annular gasket 14 which is interposed between the
faceplate and the lens. As best illustrated in FIG. 3, when the
sight glass assembly is mounted on the wall of the pressure vessel,
the faceplate 17 secured to the housing member, is received within
annular recess 32 provided in the outer surface of the wall member
of the pressure vessel, and about the periphery of the opening 18
therein.
The faceplate is secured to the housing member by means of a
plurality of flat head screws 33, which are circumferentially
spaced about the faceplate. Upon tightening the screws 34 about the
circumference of the faceplate 17, the annular flange portion 31 of
the packing member is compressed to form a seal between the
faceplate 17 and the housing member 12. In addition, the main body
of the packing member 16 is forced against the frustoconically
shaped wall 28, to produce a radially directed compressive force
against the cylindrical wall 30 of the lens. This action provides a
fluidtight seal between the housing structure and the lens, and
furthermore, places the lens 13 in radial compression. The radial
compression of the lens results in an important safety feature, in
that it substantially decreases the chances of blowout of the
lens.
The packing member 16 preferably is formed from a resilient
adhesive material such as silicone rubber, which is premolded and
adheres to the cylindrical surface 30 of the lens and the upper
surface of the faceplate 17.
The faceplate 17, lower gasket 15, lens 13 and packing member 16
are formed as an integral unit. In fabricating the unit, in one
embodiment, the gasket 15 is positioned in the annular recess of
the faceplate, the lens is mounted on the gasket 15 and then the
packing member consisting of an uncured adhesive silicone rubber is
mounted on the faceplate and lens and adheres thereto. The packing
member is then cured to complete the unit, whereby the packing
member will be firmly adhered to the lens and faceplate.
It will be appreciated that the adhesive engagement of the packing
member 16 with the components of the assembly provides a primary
sealing means between the lens and the packing member, to prevent
leakage of the medium contained in the vessel 11. In addition, the
pressure applied by tightening the screws 33 forces the packing
member against the frustoconically shaped wall 28, producing a
radial inward compressive force about the periphery of the lens to
provide a secondary sealing action between the housing member and
the lens.
The housing structure and the faceplate may be constructed of any
suitable materials although metallic materials are preferred. The
plate member 17, furthermore, preferably is formed of a corrosive
resistant material such as stainless steel. The housing structure
can be constructed of any material having suitable strength
characteristics. It is not necessary that the housing structure be
constructed of a corrosive resistant material, in that it is not
exposed or readily accessible to the fluids contained within the
pressure vessel.
The lens 13 is prevented from being placed in tension when the
bolts 22 are tightened by means of the limit of travel of the
housing member relative to the annular plate 17. The entire
assembly can be removed from the vessel, merely by removing the
bolts 22.
The packing member 16 can be made of a sufficient axial dimension
so that before the faceplate is placed in position and secured to
the housing member, the packing member will extend beyond the
surface 20 of the housing member.
FIGS. 4 and 5 illustrate another embodiment of the invention, which
particularly is adapted for use when a corrosive medium is
contained within the pressure vessel. This embodiment includes a
housing member 34, a packing member 35, a protective liner member
36, a lens 37, upper and lower cushioning gaskets 38 and 39, and a
faceplate member 40. As illustrated in FIG. 5, the second
embodiment of the sight glass assembly is adapted to be mounted on
a pressure vessel 41, having a circular opening 43 therein. The
housing member 34 is similar to the housing member described in
connection with the first embodiment, including parallel upper and
lower annular surfaces 43 and 44. The lower surface 44 is adapted
to be mounted adjacent the wall of the pressure vessel 41 in the
manner illustrated in FIG. 5. The housing member 34 also is
provided with a plurality of circumferentially spaced openings 45,
which are adapted to receive a plurality of bolts 46 for securing
the housing member to the wall of the pressure vessel. Leakage
between the sight glass assembly and the wall of the pressure
vessel is prevented by means of a suitable annular sealing gasket
47.
The housing member is provided with a circular opening 48
therethrough, having an upper beveled wall 49. The lower portion of
the opening 48 is enlarged as at 50, to provide an annular shoulder
50a and to a greater extent therebelow to provide a frustoconically
shaped wall 51. The lower surface 44 of the housing member about
the opening therein is provided with an annular beveled surface 52
which is curved inwardly and upwardly toward the inner end thereof
to merge with the frustoconically shaped wall 51.
Mountable within the opening of the housing structure is the
packing member 35 which is formed from a resilient material, as in
the case of the packing member described with the first-mentioned
embodiment. The packing member includes an annular flange portion
53, the upper surface of which engages the beveled surface 52 on
the housing member when the packing member is inserted in the
opening therein. The packing member 35 is protected from any
corrosive mediums within the pressure vessel by means of the liner
member 36. The liner member includes a cylindrical portion 54 which
is received within the opening in the packing member, and an
annular outwardly projecting flange portion 55 which engages the
lower surface of the packing member including the annular flange
portion 53 thereof. It will be seen in FIG. 5 that the packing
member 35 is completely enclosed and protected by the liner member
36. The liner member is made relatively thin and is formed from any
suitable flexible material which has corrosive resistant
properties.
The faceplate 40 is substantially annular, having an outside
diameter greater than the beveled surface 52 of the housing member
and an inside diameter slightly less than the outside diameter of
the lens 37. The upper inner end of the faceplate member is
annularly recessed to provide a space for the lower annular
cushioning gasket 39. The lens 37 has an outside diameter slightly
less than the annular recess in the faceplate member, so that there
may be provided an annular seal 56 between the lens and the
faceplate member. The lens is secured to the faceplate member with
the lower cushioning gasket 39 interposed between the lower surface
of the lens and the faceplate member, by means of the seal 56 which
also is formed from a resilient material.
With the lens mounted on the faceplate member, as illustrated in
FIG. 4, the entire unit can be inserted into the opening in the
housing member so that the upper annular cushioning gasket 38
engages annular shoulder 50a, the cylindrical surface of the lens
37 is received within and engages the cylindrical portion 54 of the
liner member, and the faceplate member 40 engages the annular
flange portion 55 of the liner member. The faceplate member is
secured to the housing structure by means of a plurality of
circumferentially spaced, flat head screws 57 as best seen in FIG.
5. When the sight glass assembly is mounted on the pressure vessel,
the faceplate 40 is received within an annular recess 58 formed in
the outer surface of the wall 41 of the pressure vessel and seated
on gasket 47 about the periphery of the opening 42 therein.
In the embodiment illustrated in FIGS. 4 and 5, a primary seal
between the faceplate member and the lens is provided by the seal
56. In addition, a secondary seal is provided when the screws 57
are tightened to compress the annular flange portion 53 of the
packing member and to force the main body of the packing member
against the frustoconically shaped wall 51, to produce a
compressive radial force against the lens 37. In this embodiment,
primary and secondary seals are provided, and the packing member is
protected from the corrosive effects of the medium within the
pressure vessel by means of the liner member 36. In addition, it
will be noted that the limit of travel of the housing member
relative to the annular force plate member 40 prevents the lens
from being placed in tension when the screws 57 are tightened to
firmly secure the faceplate member to the housing member. As
mentioned in connection with the first embodiment, the faceplate
member and the housing member can be formed of any suitable rigid
materials, although metallic materials are preferred. Furthermore,
it is preferred that the faceplate member be constructed of a
corrosive resistant material such as stainless steel, considering
that the faceplate member constantly is exposed to the interior of
the pressure vessel. The housing structure, however, need not be
constructed of a corrosive resistant material, in that it is not
exposed or readily accessible to fluids contained within the
pressure vessel. The liner member is formed from a chemical and
heat resistant, flexible material, such as Teflon.
In both of the above-described embodiments, it will be appreciated
that effective sealing means are provided to prevent leakage of the
medium within the pressure vessel between the lens and the housing
member. In addition, the lens is placed under a compressive radial
load which is effective in preventing the lens from blowing out,
thereby providing an additional safety feature for the
assembly.
From the foregoing detailed description it will be evident that
there are a number of changes, adaptations and modifications of the
present invention which come within the province of those skilled
in the art. However, it is intended that all such variations not
departing from the spirit of the invention be considered as within
the scope thereof as limited solely by the appended claims.
* * * * *