U.S. patent number 3,661,060 [Application Number 05/061,092] was granted by the patent office on 1972-05-09 for diaphragms for high pressure compressors and pumps.
This patent grant is currently assigned to The Duriron Company, Inc.. Invention is credited to John C. Bowen.
United States Patent |
3,661,060 |
Bowen |
May 9, 1972 |
DIAPHRAGMS FOR HIGH PRESSURE COMPRESSORS AND PUMPS
Abstract
Diaphragms are provided for high pressure compressors and pumps,
the diaphragms having heat insulation properties, extended life and
apparatus capable of detecting diaphragm leaks associated
therewith.
Inventors: |
Bowen; John C. (Huntingdon
Valley, PA) |
Assignee: |
The Duriron Company, Inc.
(Dayton, OH)
|
Family
ID: |
22033543 |
Appl.
No.: |
05/061,092 |
Filed: |
August 5, 1970 |
Current U.S.
Class: |
92/102; 92/5R;
417/63; 92/103SD |
Current CPC
Class: |
F04B
43/009 (20130101) |
Current International
Class: |
F04B
43/00 (20060101); F01b 019/00 (); F16j 003/00 ();
F04b 021/00 () |
Field of
Search: |
;417/63,395
;92/102,103,13M,13SD,13R,98 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Walker; Robert M.
Claims
I claim:
1. In combination with metal mounting heads having a diaphragm
chamber therebetween,
a diaphragm assembly carried by said heads in said chamber,
said diaphragm assembly comprising a plurality of metal diaphragm
plates, and
a plurality of spaced heat insulating and fretting corrosion
deterring films interposed between said metal diaphragm plates and
said mounting heads at the periphery of said plates.
2. The combination as defined in claim 1 in which
a central plate of reduced diameter is interposed between a pair of
said metal diaphragm plates.
3. The combination as defined in claim 2 in which
said central plate is circular and is provided with at least one
fluid delivery passageway communicating with the periphery of said
central plate.
4. The combination as defined in claim 3 in which
said fluid delivery passage is a radial slot.
5. The combination as defined in claim 3 in which
said fluid delivery passage is a radial groove.
6. The combination as defined in claim 3 in which
said central plate is of synthetic plastic.
7. The combination as defined in claim 3 in which
said central plate is of metal.
8. The combination as defined in claim 3 in which
means are associated with said diaphragm assembly for detecting
fluid leakage through said passageway.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to diaphragms for high pressure compressors
and pumps and more particularly to diaphragms which reduce heat
transfer with respect to the fluid being compressed or pumped by
the diaphragm while at the same time providing for diaphragm leak
detection.
2. Description of the Prior Art
It has heretofore been proposed to provide laminated diaphragms for
low pressure service. Examples of such diaphragms are shown by
McFarland, U.S. Pat. No. 2,918,089 and Lang, U.S. Pat. No.
3,049,931. These and similar diaphragms are not suitable for high
operating pressures of the order of 5,000 psi and higher.
Serious difficulties have been encountered in high pressure service
because of the fretting corrosion which occurs. In my application
for patent filed June 3, 1970, Ser. No. 42,957 provisions are made
for avoiding fretting corrosion and greatly increasing the life of
a diaphragm.
The diaphragm there shown comprises a central metal plate with a
film or coating interposed between the diaphragm and the
casing.
Serious difficulties have heretofore been encountered, also with
high pressure service, if the temperature of the fluid being
compressed or pumped was at a temperature either too high or too
low to be compatible with the fluid utilized for actuating the
diaphragm.
Avoidance of contamination of the fluid being pumped or compressed
is also highly important for proper operation.
SUMMARY OF THE INVENTION
In accordance with the invention a diaphragm assembly is provided
for high pressure pumps and compressors which is free from fretting
corrosion, which is suitable for greatly reducing heat transfer
through the diaphragm assembly, and which provides for leak
detection so that contamination of the working fluid can be
avoided.
It is the principal object of the present invention to provide an
improved diaphragm assembly for high pressure pumps and compressors
which will obviate serious problems which have arisen with
diaphragms heretofore employed and with particular respect to
fretting corrosion, heat transfer and contamination of the fluid
being pumped or compressed.
It is a further object of the present invention to provide a
diaphragm assembly of the character aforesaid which will have a
long life and which will be reliable in service.
Other objects and advantageous features of the invention will be
apparent from the description and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The nature and characteristic features of the invention will be
more readily understood from the following description taken in
connection with the accompanying drawings forming part thereof, in
which:
FIG. 1 is a fragmentary transverse sectional view of a portion of a
high pressure pump or compressor incorporating the diaphragm
assembly in accordance with the invention;
FIG. 2 is an enlarged view of a portion of FIG. 1;
FIG. 3 is a fragmentary plan view on a smaller scale of an
intermediate diaphragm element; and
FIG. 4 is a fragmentary plan view on a smaller scale of a different
form of intermediate diaphragm element.
It should, of course, be understood that the description and
drawings herein are illustrative merely and that various
modifications and changes can be made in the structure disclosed
without departing from the spirit of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more particularly to the drawings, a portion of a
high pressure pump or compressor similar to that in my prior U.S.
Pat. No. 3,318,250, is shown and includes an upper diaphragm
mounting head 10, a lower diaphragm mounting head 11 and a
diaphragm assembly 12 with an interposed limit plate 14.
The diaphragm assembly 12 may be moved in any desired manner such
as by liquid acting on the underside thereof and effective through
the limit plate 14 as in my prior Pat. No. 3,318,250.
A suitable packing 15 such as metallic rings may be provided in
grooves 16 in the upper and lower heads 10 and 11.
The plate 14 has a plurality of fluid delivery bores 17
therethrough communicating with a dished face 18 for engagement and
limiting of the movement of the diaphragm assembly 12. The upper
head 10 has a fluid delivery bore 20 extending through the head 10
for delivery of fluid which has been compressed or pumped. Inlet
and delivery valves (not shown) of any suitable type can be
employed, such as those shown in U.S. Pat. No. 3,425,429 of Bacino
and Bowen.
The lower head 11 has an inlet bore 21 connected to a supply of
fluid (not shown) for delivery of fluid to actuate the diaphragm
assembly 12 and pump or compress fluid above the assembly 12. The
fluid used to actuate the diaphragm is generally a hydraulic fluid
of mineral or spirit type and which can withstand a limited range
of operating temperature variation.
The diaphragm assembly 12 has an upper diaphragm plate 25, a
central plate 26 and a lower diaphragm plate 27.
The central plate 26 as viewed in FIG. 3 is circular and provided
with a radial cut out or groove 30 to permit escape of any fluid
which may leak through the upper plate 25 or the lower plate 27. As
seen in FIG. 4, the plate 26a, in place of the groove 30, can have
score lines 30a to permit of escape of fluid. The diaphragm plates
26 and 26a can be fabricated of a heat insulating plastic or of
metal in accordance with the demands of a particular
installation.
The upper diaphragm plate 25, the central plate 26 and the lower
diaphragm plate 27 may be coated with a heat insulating friction
reducing and particle absorbent film 31. The film 31 should be
suitable for the process to be carried out, adherent to metal and
not subject to removal by scuffing, resistant to flow when
subjected to stress and motion, must allow limited sliding movement
to occur between the diaphragm assembly 12 and the heads 10 and 11
and thereby reduce fretting corrosion, must be capable of absorbing
small quantities of solid particles to prevent concentrated
stresses from occurring and must have insulating
characteristics.
A particularly suitable material for the film is available from E.
I. du Pont de Nemours & Co., Wilmington, Del., under the name
Teflon (Compound 958-203), this being a fluorocarbon resin with
modifiers dispersed in an organic solvent for spray
application.
Other suitable materials for the film are Rulon R-75, a
fluorocarbon resin with modifiers dispersed in an organic solvent
for spray application available from Penn-Dixon Corporation,
Clifton Heights, Pa.; Ekonol, a polyester based on p-hydrobenzoic
acid, available from Carborundum Corp., Niagara Falls, N.Y.;
Emralon, available from Acheson Colloids Corp. of Port Huron,
Mich.; and Vespel, a polyimid available from E. I. du Pont de
Nemours & Co., Wilmington, Del.
A thickness of film in the range from about 0.2 to 5 1,000ths of an
inch has been found to be satisfactory, dependent on the strength
of the film and on the bond. If the strength of the film is not
great it will flow. If this happens the stresses in the diaphragm
assembly may exceed the "elastic limit" and a thinner film must be
employed to prevent failure.
The film 31 can be applied to both sides of the upper and lower
diaphragm plates 25 and 27 and the central plate 26. The heads 10
and 11 may also have the film 31 on the face 18 of the lower head
and the face 32 of the upper head if desired.
The lower head 11 has a bore 35 therein which communicates with the
opening between the upper and lower diaphragm plates 25 and 27 and
extends to a threaded bore 36.
A pipe 37 is engaged with bore 36 and connected to a pressure
sensitive gauge 38 which has a pipe 39 connected to its other side
and to a pressure switch 40 of conventional well known type. The
switch 40 is connected to a circuit (not shown) which controls the
hydraulic fluid pumped into the bore 21 for diaphragm actuation and
may shut off the fluid flow should pressure from leaks be effective
at switch 40. A pressure relief valve 42 is connected to the switch
40 and a manually operated vent 43 is also connected to the switch
40. With the protective film as described coating the various parts
of the diaphragm assembly 12 and the heads 10 and 11, high or low
temperatures of the fluid to be compressed or pumped which might be
beyond the proper operating limits of the pumping fluid will not be
adversely effective on the pumping fluid because of the temperature
insulating and isolating qualities of the diaphragm assembly
attendant on the use of the plurality of films 31 with or without
enhancement by a central plate 26 of low heat conductivity.
In addition should the upper diaphragm plate 25 or the lower plate
26 rupture or fail the leaking fluid will flow out through groove
30 in plate 26 or score line 30a in plate 26a through bore 35, pipe
37 to pressure gauge 38 and through pipe 39 to pressure switch 40
so that the pressure rise will be apparent on gauge 38, and
pressure switch 40 will cut off the flow of pumping fluid which
actuates the diaphragm assembly 12 so that contamination of the
fluid being pumped and damage will not be inflicted on the
diaphragm assembly.
It will thus be seen that apparatus has been provided with which
the objects of the invention are attained.
* * * * *