U.S. patent number 3,581,441 [Application Number 04/754,094] was granted by the patent office on 1971-06-01 for surface treatment apparatus.
This patent grant is currently assigned to W. D. Gunnels. Invention is credited to Clarence E. Hulbert, Jr..
United States Patent |
3,581,441 |
Hulbert, Jr. |
June 1, 1971 |
SURFACE TREATMENT APPARATUS
Abstract
Apparatus and method of conveying granular material substantial
distances from an open storage container through vessel means which
provides alternate vacuum and pressure to chamber means in said
vessel means to said material from said vessel means continuously
over substantial distances. Distributor outlet means are provided
for discharging said material continuously. Tower means may be
utilized to position said distributor outlet means whereby a
uniform anchor pattern is provided on a surface in proximity to
said distributor outlet means.
Inventors: |
Hulbert, Jr.; Clarence E.
(Houston, TX) |
Assignee: |
W. D. Gunnels (Freeport,
TX)
|
Family
ID: |
25033465 |
Appl.
No.: |
04/754,094 |
Filed: |
August 9, 1968 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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463781 |
Jun 14, 1965 |
|
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Current U.S.
Class: |
451/2; 451/101;
451/102; 451/76 |
Current CPC
Class: |
B05B
7/1477 (20130101); B24C 3/062 (20130101); B24C
7/0046 (20130101); B05B 13/005 (20130101); B05B
7/1404 (20130101) |
Current International
Class: |
B24C
3/00 (20060101); B24C 3/06 (20060101); B24C
7/00 (20060101); B05B 13/00 (20060101); B05B
7/14 (20060101); B24c 003/06 () |
Field of
Search: |
;51/8,11,12,14
;302/28,64 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Swingle; Lester M.
Parent Case Text
This application is a continuation of my application Ser. No.
463,781 filed June 14, 1965, and now abandoned.
Claims
I claim:
1. A distributor head for distributing sand from a source to
plurality of sandblasting nozzles including in combination
a hollow cylinder,
an upper plate fixedly coupled to said cylinder,
lower plate means fixedly coupled to said cylinder, said lower
plate means including a sand inlet, and a plurality of said outlets
each disposed substantially the same distance from said inlet, and
in communication with said sandblasting nozzles,
and means for connecting said sand inlet to a source of sand.
2. A distributor head for distributing sand from a source to a
plurality of sandblasting nozzles, comprising
a housing having a first end and an opposite end spaced away from
said first end,
connection means in said first end adapted to be connected to said
sand source to conduct sand from said source to the interior of
said housing and direct it toward the opposite end of said housing,
the distance from the interior end of the connection means to the
opposite end of the housing being substantially as great as the
distance between the first end of the housing and the opposite
end,
and a plurality of sand outlets in said first end of said housing,
each disposed substantially the same distance from said connection
means,
whereby sand entering the housing must turn substantially
180.degree. therein before exiting through the outlets, thereby
building up static sand in the housing to protect the housing from
wear.
3. A distributor head as defined by claim 2 wherein said housing
comprises an outer housing between the first end and the opposite
end, and an inner housing between the first end and the opposite
end, the inner housing being in the form of a sinuous wall
extending outwardly to enclose each outlet and inwardly toward the
connection means intermediate the outlets.
4. An apparatus for providing treatment to a surface, said
apparatus including in combination
first means including guide tower means having a vertically movable
single column structure, distributor head and nozzle means coupled
to said column structure, and trolley means supporting said first
means, said trolley means including a horizontally extending member
having a plurality of rollers pivotally coupled to said
horizontally extending member and a vertically extending member
coupled to said horizontally extending member and having a roller
pivotally coupled to said vertically extending member, said first
means being disposed near the surface to be treated, and
second means coupled to said column structure for providing
controlled movement of said first means.
Description
This invention pertains generally to automatic cleaning equipment
and methods and particularly to equipment and methods which may be
utilized in moving products substantial distances while maintaining
a velocity of the product at a greater rate than has been
heretofore obtained.
Sandblasting is old in the art. Many devices have provided a source
of abrasives, passed such abrasives through suitable equipment to
increase the velocity of the abrasive, and discharge the abrasive
through a nozzle onto a surface to be cleaned. The surface to be
cleaned had a variable anchor pattern or holding quality because
the manual movement of the nozzle caused the nozzle to be at a
varying distance and angle from the surface to be cleaned, thereby
causing a variable anchor pattern to be formed on such surface. As
set forth in Surface Preparation Specifications No. 5 Blast
Cleaning to "White" Metal, approved as tentative Aug. 28, 1952 by
Steel Structures Painting Council, 4400 Fifth Avenue, Pittsburgh,
Pennsylvania on page 2, paragraph 3.8: "The height of profile of
the anchor pattern produced on the surface shall be limited to a
maximum height that will not be detrimental to the life of the
paint film." On page 3, paragraph A.3 is the following: "The
maximum height of profile is the height of the anchor pattern
produced on the surface, measured from the bottoms of the lowest
pits to the tops of the highest peaks . . . the allowable maximum
height of profile is, in turn, dependent upon the thickness of
paint to be applied." It is impossible to produce a
quality-controlled anchor pattern by manual means. The present
invention has created the first method controlled by angle,
distance and constant velocity of abrasive emitting from the
nozzles to produce a true height and depth control of anchor
pattern for the purpose of controlling the uniform etched surface.
The paint or coating film of uniform thickness known to exist from
the tip of the highest peak to the exterior surface of the paint
film, depends upon uniformity of the profile of the surface thereby
enabling control of the thickness and adding longevity and
durability to the coating system used when applied over this method
of sand blasted surface. Heretofore known manual means cannot
accomplish this result yet it is desired by all who apply or
manufacture paints or coatings and by the recipients of those
services. Equipment which has been available in the past has been
cumbersome and has not provided adequate velocity through conduits
so that long lengths of hose could be used with such cleaning
equipment. Also, automated cleaning equipment has been limited
generally to flat surfaces on substantially small workpieces. Among
the expired patents which show various types of abrasive cleaning
equipment and methods are the following:
U.S. Pat. No. 1,462,296, Moore et al., issued July 17, 1923.
U.S. Pat. No. 1,616,777, Booth, issued Feb. 8, 1927.
U.S. Pat. No. 1,625,721, Hahn, issued Apr. 19, 1927.
U.S. Pat. No. 1,635,539, Coleman et al., issued July 12, 1927.
U.S. Pat. No. 1,858,474, Wolever, issued May 17, 1932.
U.S. Pat. No. 2,380,738, Eppler, issued July 31, 1945.
U.S. Pat. No. 2,409,722, Stark et al., issued Oct. 22, 1946.
Among the prior art patents which have not expired but which
indicate various types of cleaning equipment and methods, are the
following:
Reissue U.S. Pat. No. 23,186, Mead, issued Jan. 3, 1950. U.S. S.
Pat. No. 2,597,434, Bishop et al., issued May 20, 1952.
U.S. Pat. No. 2,570,603, Shoemaker, issued Oct. 9, 1951.
U.S. Pat. No. 2,845,091, Neer, issued July 29, 1958.
U.S. Pat. No. 3,015,913, Anderson, issued Jan. 9, 1962.
U.S. Pat. No. 3,139,705, Histed, issued July 7, 1964.
U.S. Pat. No. 3,179,378, Zenz et al., issued Apr. 20, 1965.
One of the major cleaning problems in the sandblasting or abrasive
cleaning art has been in the cleaning of large oil and petroleum
products storage tanks which are generally cylindrical in shape
except for the upper part of such tank. The upper part of such
tanks is conical. Some oil storage and petroleum products storage
tanks have a floating or variable position top which prevents
evaporation from being as great as would be encountered if the top
was not a floating top. Present practice in cleaning such oil and
petroleum products storage tanks involves having cumbersome
scaffolding and cumbersome equipment when cleaning the outside and
the inside of such tanks. Many men are needed to operate the
equipment which has heretofore been used in cleaning such oil and
petroleum products tanks. The danger to men working on the
scaffolding in cleaning both the exterior and interior of the tanks
has been great due to the possibility of men falling from the
scaffolding and from the tanks. Also, the men who have been
cleaning such tanks have been subjected to silicosis. In cleaning
the inside of such tanks, an additional danger has been the
possibility of workmen being overcome by fumes from the products
being stored in such tanks as well as the excessive temperature and
poor air circulation on the inside of such tanks. The present
invention is directed to overcoming and eliminating many of the
problems heretofore encountered in the cleaning, particularly
petroleum and chemical products storage tanks, ships, barges, and
the like not excluding buildings, dams, and other structures, but
the present invention also is adaptable for use in a plurality of
endeavors which will be set forth in detail later.
Thus, it is an object of the present invention to provide improved
equipment for cleaning and coating surfaces, particularly the
exterior and interior surfaces of products storage tanks.
Another object of the present invention is to provide an apparatus
for cleaning a surface whereby such surface is provided with
uniform anchor pattern for the purpose of painting or applying a
protective coating film, the uniform thickness of such coating film
being essential to the life of such coating film.
Still a further object of the present invention is to provide
cleaning apparatus wherein a single human operator is capable of
remotely controlling the cleaning operation on the surface to be
cleaned. A still further object of the present invention is to
provide improved cleaning equipment, utilizing simplified equipment
and less man power.
Yet another object of the present invention is to provide cleaning
equipment wherein workmen are removed from the hazards of dust,
fumes, and temperature extremes.
Yet another object of the present invention is to provide cleaning
equipment wherein scaffolding is eliminated, thereby preventing
accidents to workmen which have been required in the past to work
on such scaffolds.
A still further object of the present invention is to provide
cleaning equipment wherein fewer workmen are required.
Yet another object of the present invention is to provide cleaning
equipment wherein workmen no longer need to handle or hold a
high-pressure sandblast hose at dangerous elevations while working
on surfaces to be cleaned.
A still further object of the present invention is to provide
equipment for cleaning the interior of tanks in a safe, fast, and
controlled manner.
A further object of the present invention is to provide an improved
distributor head characterized by smaller friction loss.
Yet another object of the present invention is to provide a
universal cleaning rig structure adaptable for use on various
configurations, sizes, and types of vessels to be cleaned.
Briefly stated, the present invention includes an apparatus for
providing uniform anchor pattern characteristics to a surface to be
cleaned. The equipment of the present invention when utilized for
cleaning a surface includes a source of cleaning material such as
sand or other abrasives, compressor means, pressure vessel means
coupled to said compressor means and to the source of cleaning
material, means coupled to the vessel means for providing
continuous flow of abrasives from the vessel means, trolley means
and guide tower means coupled to the surface to be cleaned, and
distributor and nozzle carrier means coupled to the guide tower
means and trolley means. The vessel means of the present invention
include an upper inlet portion which acts both as a high-pressure
and low-pressure chamber and a lower portion wherein high-pressure
is maintained continuously. Means are provided in the vessel means
between the upper chamber and lower chamber to allow sand or other
material moving through said vessel to be dropped from the upper
chamber to the lower chamber whenever the level in the upper
chamber reaches a selected amount. Handle means are also provided
on the vessel means to allow material which has accumulated near
filters positioned near the outer portion of said vessel means to
be dropped into the upper chamber of said vessel means. A moisture
bleed is provided near the lower chamber to allow removal of
moisture which accumulates in the bottom of the vessel means. An
important feature of the vessel means is the movement of abrasive
material in said vessel means. Movement of material in the vessel
means provides minimum friction loss while allowing maximum use of
suction created by blower means coupled to the vessel means. The
vessel means further includes a discharge outlet which may be moved
to a limited extent to provide constant metered quantity and
velocity to the abrasive or other material being discharged from
the lower portion of the vessel means. The guide tower means and
trolley means are suspended from the surface to be cleaned with the
trolley means providing horizontal movement to the vertical guide
tower means. Horizontal movement of the trolley and guide tower
means is achieved remotely by an operator controlling the entire
cleaning operation. Distributor and nozzle means are coupled to the
guide tower and trolley means with the distributor and nozzle means
moving vertically along the guide tower means. Vertical movement of
the distributor head and nozzle means also is accomplished remotely
by the same operator who controls the horizontal movement of the
guide tower means and trolley means. The guide tower means provides
a controlled cleaning path for the nozzle means. Thus, it will be
appreciated that the distributor head and nozzle means where the
cleaning substance is discharged against the surface to be cleaned
may be moved vertically and horizontally simultaneously by the
operator thereby allowing the operator to write his name, for
example, on the surface being cleaned. The position of the
distributor head and nozzle means from the surface being cleaned is
maintained at a substantially constant angle and substantially
constant distance from such surface to provide a substantially
constant, uniform anchor pattern on the surface being cleaned.
Thus, the surface being cleaned will retain paint or other coatings
applied to such surface after the cleaning operation is completed
much better than a surface which does not have a uniform anchor
pattern. Although the invention has been described briefly in
connection with a cleaning operation of a surface, it will be
appreciated that the principles involved in the present invention
allow such invention to be used for the purpose of applying paint
and other coatings to such surface automatically. Although the
invention has been described briefly with the cleaning operation of
a surface, it will be appreciated that the invention allows
movement of liquids and solids from storage facilities at a rate
heretofore unattainable. The present invention may be utilized, for
example, in loading or unloading grain or other materials to or
from the hold of a ship, storage bin, or other storage facility
where it is difficult or impossible to locate workmen or to provide
equipment which heretofore would satisfactorily perform the
required operation.
In the drawings FIG. 1 is a perspective sketch showing the present
invention utilized in cleaning storage tanks;
FIG. 2 is a combined flow sheet and sketch of the present invention
used in cleaning tanks;
FIG. 3 is a sectional elevational view of the vessel means of the
present invention;
FIG. 4 is a sectional elevational view of the outlet means of the
vessel means shown in FIG. 3;
FIG. 5 is a top view of the guide tower means and trolley means of
the present invention;
FIG. 6 is a side elevational view of a portion of the guide tower
means and trolley means shown in FIG. 5;
FIG. 7 is a side elevational view showing a portion of the guide
tower means and the trolley means of the present invention when
used on another type tank;
FIG. 8 is an elevational view of the trolley means shown in FIG. 7
taken from the upper tank side;
FIG. 9 is a top plan view of the distributor head and nozzle means
of the present invention;
FIG. 10 is a side elevational view of the distributor head and
nozzle means of the present invention;
FIG. 11 is a bottom view of the distributor head of the present
invention;
FIG. 12 is a sectional elevational view of the distributor head
taken along line 12-12 of FIG. 11;
FIG. 13 is a sectional elevational view of the distributor head of
the present invention taken along line 13-13 of FIG. 11;
FIG. 14 is a top plan view of a conventional nozzle moved about a
fixed radius;
FIG. 15 is a top plan view of a surface showing the anchor pattern
when cleaned in the manner shown in FIG. 14;
FIG. 16 is a top plan view showing a surface and the coating
thereon when an anchor pattern shown in FIG. 15 is present;
FIG. 17 is a top plan view showing a plurality of nozzle positions
in accordance with the present invention;
FIG. 18 is a top plan view of a surface which has been cleaned in
accordance with the present invention showing a uniform anchor
pattern on the cleaned surface;
FIG. 19 is a top plan view of the surface shown in FIG. 18 wherein
such surface has been coated;
FIG. 20 is a top plan view in section showing the vessel means of
the present invention;
FIG. 21 is a sectional elevational view taken along line 21-21 of
FIG. 20;
FIG. 22 is a partial sectional elevational view showing the upper
inside portion of a tank being cleaned in accordance with the
present invention;
FIG. 22 is a partial sectional elevational view of the interior of
a storage tank being cleaned in accordance with the present
invention;
FIG. 23 is a partial sectional elevational view showing the upper
inside portion of a tank being cleaned in accordance with the
present invention;
FIG. 24 is a side elevational view of a tank being cleaned in
accordance with the present invention;
FIG. 25 is a partial sectional perspective view of the guide tower
means coupling shown in FIG. 24; and
FIG. 26 is a sectional top view of the fastening means shown in
FIG. 25.
Referring now to the drawings in detail, FIG. 1 is a perspective
sketch showing a typical use of the present invention. A plurality
of oil storage tanks 10, 12 and 14 are shown. It will be
appreciated that oil storage tanks 10, 12, and 14 are provided with
steps 10A, 12A, and 14A to allow personnel to go from the ground to
the top of the tanks. Also, mounds of earth such as 10B, 12B, and
14B surround each one of the respective tanks.
The elevated protective banks 10B, 12B, and 14B surrounding each
one of tanks 10, 12 and 14, respectively, act to protect the lower
portion of the tanks and to act as an auxiliary storage area in the
event liquid leaks from the tanks thereby minimizing fire hazards
in the event that tanks 10, 12, and 14 contain combustible liquids.
The banks such as 10B, 12B, and 14B present problems, however, when
conventional cleaning methods are utilized in cleaning the surfaces
10C, 12C, and 14C of the tanks. Also, steps 10A, 12A, and 14A
present a problem in positioning scaffolding and workmen on the
exterior of the tanks when such tanks are cleaned by conventional
apparatus and conventional methods.
Tank 14 is shown in FIG. 1 being cleaned by the apparatus of the
present invention. A hopper 40 is utilized in storing abrasive
material such as sand 42. Hopper 40 may be open as shown to allow
abrasives such as sand or other material to be positioned in the
hopper. By having an open hopper such as the hopper shown in FIG.
1, workmen can visibly ascertain when additional material is needed
to be placed in the hopper. Also, by having an open hopper there is
no necessity for utilizing overhead hoppers or pressurized vessels
for storing abrasives or other material in the manner previously
utilized in known prior art apparatus. The open hopper allows sand
or other abrasives to be positioned in the hopper at any convenient
time and in variable quantities, inasmuch as the operation of the
storage hopper is not dependent upon any fixed level or amount of
abrasive material 42 positioned in such hopper. The portable hopper
40 shown in FIG. 1 allows easy loading from dump trucks or other
rapid loading means.
A suitable conduit such as hose 44 is coupled at 46 to the hopper
40. Hose 44 extends upwardly to the vessel means 50. Vessel means
50 will be explained in detail subsequently, inasmuch as such
vessel means is an important part of the present invention. Suffice
it to say for the present, however, the vessel means 50 has an
intake section 52 where the abrasive 42 enters the vessel means
50.
Coupled to vessel means 50 is a suitable air compressor 20 which
may have, for example, a 1,200 cubic feet per minute capacity.
Compressor 20 is coupled through suitable conduits such as hose 22
to a reservoir tank 24. Reservoir tank 24 is coupled to vessel
means 50 through suitable pipe means 54 having a two-way
remote-operated valve 48. The air compressor provides the
pressurized air which is utilized in vessel means 50 in a manner to
be explained hereinafter to allow pressurized abrasive 42 to pass
through pressure outlet hose 16 to the distributor head and nozzle
means 34 positioned on guide tower means 32. Guide tower means 32
is suspended by trolley means 36 from the upper portion of tank 14
in a manner to be explained subsequently. An operator 60 is
positioned at a suitable location to cause horizontal movement of
trolley means 36 and guide tower means 32. Operator 60 further
provides vertical movement of the distributor head and nozzle means
34 through a control box 30 coupled through lead 62 to an
instrument control box held by operator 60. Lead 64 also comes from
the instrument control box panel held by operator 60 and is coupled
to trolley means 36 to effectuate horizontal movement of the
trolley means 36 to guide tower means 32 in a manner to be
explained subsequently. It will be appreciated that the guide tower
means 32 is not rigidly or movably coupled to the earth or to bank
14B surrounding tank 14, but guide tower means 32 and trolley means
36 move around the periphery of tank 14 without substantial contact
at the lower portion of guide tower means 32 with the earth.
Also coupled to vessel means 50 is a blowdown valve 53 and an
exhauster or blower 28 which is driven by suitable motive means
such as a motor 26. The function and operation of the exhauster or
blower 28 will be explained subsequently in connection with the
detailed explanation of the interior operation of vessel means 50.
A suitable manifold exhaust 29 also is coupled to blower or
exhauster 28.
It will be appreciated that the vessel means 50 and associated
components may be skid mounted on a suitable plate 70. Such plate
or skid 70 may be provided with wheels to allow the vessel means 50
to be easily and effectively moved to desired locations with a
minimum amount of effort. Thus, it will be appreciated in viewing
the overall system shown in FIG. 1 that operator 60 by simply
manipulating a hand-carried group of switches or buttons on the
instrument control box to remotely control the cleaning operation
of surface 14C of tank 14. The movement of the nozzles which
discharge the abrasive under pressure from pressure outlet 16 are
movable vertically and horizontally simultaneously so that, for
example, operator 60 could write his name on surface 14C. The
movement and cleaning swath accomplished with the present invention
is thought to be completely new and allows effective, rapid, and
safe cleaning of surfaces with a minimum amount of man power and
equipment required. As stated previously, although all of the
components shown in FIG. 1 may be utilized in practicing the
present invention vessel means 50 and distributor head and nozzle
means 34 along with guide tower means 32 and trolley means 36 are
an important part of the invention.
Referring now to FIG. 2, a combined flow chart and diagrammatic
layout is shown in FIG. 2. Hopper 40 is shown containing abrasive
such as sand 42. The abrasive or sand 42 passes through flow line
44 to the intake 52 on vessel means 50. As explained previously, an
exhauster or blower 28 is coupled to vessel means 50 through line
128. Reservoir tank 24 is coupled to the upper part of the vessel
means 50 through valve 77 in line 76 and valve 74 is coupled to the
lower portion of the vessel means 50. Valve 77 is coupled to panel
30 through line 79. The discharge from vessel means 50 passes
through line 78 to the distributor head and nozzle means 34
positioned on guide tower means 32. Guide tower means 32 is coupled
to trolley means 36 and cable 80 provides vertical movement of the
distributor head and nozzle means 34 along guide tower means 32 in
a manner to be explained subsequently. Cable 80 is coupled to a
winch 82 on trolley means 36. Winch 82 may be driven by a pneumatic
motor 84 or other suitable power means positioned on the trolley
means 36 with pneumatic motor 84 being coupled to valve 88. Valve
88 and valve 98 are coupled through line 86 to air compressor 20
which may be driven by an electric motor 21 or other suitable power
means. It will be appreciated that another pneumatic motor 92 is a
component of the trolley means 36 and pneumatic motor 92 drives a
smaller diameter wheel positioned between wheels 100 and 102 to
cause movement of the trolley means 36 around the periphery of tank
14 so that surface 14C is cleaned. Pneumatic motor 92 is coupled
through line 96 to valve 98. Pneumatic line 86 is coupled to line
90 to air compressor 20. Pneumatic line 86 is coupled to a manifold
in unit 374. Valves 88 and 98 are double-acting electric
solenoid-actuated air valves and are operated by line 62 to box 87
which is manually operated by a workman through power source 30 and
line 64. Block 31 is a commercial power source or generator coupled
through line 33 to panel 30. It is possible to actuate box 87 by
suitable signals from a transmitter capable of transmitting an
actuating electromagnetic signal. Further it may be noted that
limit switches and timer devices may be incorporated on the guide
tower means 32 and on the trolley means 36 to actuate the control
solenoids in unit 374. The selection of manual control or automatic
control may be made by selecting a type of operation in box 87.
Line 90 from air compressor 20 is coupled through line 110 to valve
112 and to the reservoir tank 24. Blowdown valve 53 is coupled
through line 55 to panel 30. Panel 30 provides an electric source
through lead 114 to electric motor 21 and through lead 130 to
electric motor 26. Panel 30 provided an electric source through
line 203 to control devices 183 and 205 on vessel means 50. Control
devices 183 and 205 may be of the type known in the trade as
ROTO-BIN-DICATORS marketed by The Bindicator Company, 17190 Denver
Avenue, Detroit, Michigan and shown in catalog BD-15B-7500-7-61.
Blower 28 has coupled thereto exhaust 29 and blower 28 is driven by
an electric motor 26 coupled through lead 130 to panel 30.
In viewing FIG. 2 it will be noted that panel 30, power source 31,
box 87, and units 183, 205 and 374 act to provide effective
operation of the system of the present invention. As explained
previously, air compressor 20 provides air pressure to reservoir
tank 24 through valve 112. Valves 53, 77, 88, 98, and 126 may be
double-acting electric solenoid air valves or other suitable means
such as air-controlled valve operators or manually operated valves
such as are commercially available to operate effectively with
water or other liquids as well as air. Such valves generally are
rated at 150 pounds per square inch. The pressure in the upper and
lower portions of the vessel means 50 is equalized periodically in
a manner to be explained subsequently. Valve 88 controls pneumatic
motor 84 which in turn provides rotation to winch 82 thereby
causing the distributor head and nozzle means 34 to move vertically
because of the coupling to winch 82 through cable 80 past sheave
83. Valve 98 provides actuation to pneumatic motor 92 to cause
horizontal movement of the trolley means 34 through rotation of
wheels 100 and 102 on tank 14, thereby providing horizontal
movement near the tank. Valve 112 is opened upon actuation of the
system to allow continuous flow of air from air compressor 20 to
reservoir tank 24.
Referring now to FIG. 3, vessel means 50 of the present invention
is shown in sectional elevational form. As explained previously,
intake 52 in the upper portion of the vessel means allows products
to be brought into the vessel means 50. The products which may be
passed into the vessel means 50 may be liquid or solid. The only
limitation on the type product which may be passed through the
vessel means 50 is the ability of such product to move through a
conduit such as pipe. The product brought through inlet 52 passes
through a circular chamber such as a pipe 132. Pipe 132 is
positioned substantially in the upper portion of the vessel means
in order to enter near outer limits of the interior shell of top
inner chamber 186. The upper portion of the vessel means includes
an outer shell 134 and a cylindrical portion 136. The cylindrical
portion 136 has a conical portion 138 coupled thereto. Conical
portion 138 is positioned within shell 140 which is substantially
the same as many conventional tanks insofar as the external portion
of the tank is concerned. Thus, upper portion 142 of the interior
tank has a configuration similar to the configuration of upper
portion 134 to allow chamber 144 to be provided. Chamber 144
extends downwardly between outer shell 140 and 136 to form chamber
150. A plurality of filters such as filters 146 and 148 shown in
FIG. 3 are positioned in chamber 150 extending around chamber 186.
A vacuum pressure relief valve 154 is coupled to the upper portion
134 of the vessel shell and a pressure relief blowdown valve 53
also is coupled to upper portion 134 on the other side of product
inlet 52. Inlet 158 is coupled through chamber 160 to provide a
suction source. Chamber 160 is a manifold whereby a plurality of
filters such as 146 and 148 are attached extending
circumferentially around the interior of the exterior wall 136 and
interior wall 140 in chamber 150. Doors may be provided in wall 136
to provide access to filters such as 146 and 148 for easy service
and replacement of the filters. The filters such as 146 and 148 may
be of the perforated cylinder type with filter cloth and screw
attachment provided to fasten the filters to manifold 160. The
upper inner chamber 186 is a product collecting and metering system
and contains a centripetal particle separator. The exterior chamber
150 is a product classifier and injection system. Portions 194, 198
and 202 are openings with portions 198 and 202 coupled to handles
192 and 196 respectively to allow material accumulated in chamber
150 to pass into top inner chamber 186, thus allowing full recovery
of product brought into vessel means 50. Inlet 158 is coupled to
blower 28 shown in FIG. 1 and provides suction force for the vessel
means 50.
Referring to FIG. 20, taken along line 20-20 of FIG. 3, baffle 162
is rigidly coupled by members 164 and 166 to shell 140. It will be
appreciated that the baffle 162 is solid and shaped as half an
open-ended cylinder with curved lip portions 168 and 170 coupled
respectively to edge 172 and 174. Product inlet 132 shown in FIG.
20 is coupled through pipe 178 to an on-off product intake valve
256 which is coupled at 180 to a valve 77 shown in FIG. 3 which is
coupled to a commercial level-indicating device known as a
BIN-DICATOR as explained previously. The upper BIN-DICATOR portion
is indicated generally as 183 in FIG. 3 and includes a rotating
element 184 and a shaft 182. The upper BIN-DICATOR 183 indicates
when material reaches the level of the rotating vane 184 to stop
rotation of such vane thereby indicating that the product has
reached the level which has been set by movement of the shaft 182
within chamber 186. Chamber 186 is the product-collecting section
in the upper portion of the vessel means 50 within tank shell 140.
It will be appreciated in viewing FIG. 20 that chamber 150 extends
as a concentric ring or annulus about shell 140 and inside of shell
136.
Thus, when referring to FIG. 21 taken along line 21-21 of FIG. 20,
it will be apparent that the product entry through intake section
52 moves into chamber 186 as shown with incoming product hitting
the product 42 already positioned in chamber 186. Movement of the
product is across chamber 186 of FIG. 21 with a circular, upward
movement occurring near baffle 162 into chamber 144 between outer
shell 134 and shell 142. In viewing FIG. 21 it will be noted that
inlet 52 is located behind baffle 162 extending into top inner
chamber 186 one-half the longitudinal axis distance of 162. Opening
171 is located directly on the opposite side of baffle 162 in
relation to inlet 52. The phenomena occurring in chamber 186 will
be explained subsequently. Filters 188 and 190 are shown positioned
in chamber 150. Movement of fine product occurs through chamber 144
downwardly as indicated past filters 188 and 190 as well as other
filters extending around the entire periphery of chamber 150 so
that fine material 42A accumulates at the juncture of shell 136 and
shell 140 which is chamber 150.
Thus, it will be apparent in viewing FIG. 20 and FIG. 21 and FIG. 3
that entry of the product is into chamber 186 with a centripetal
movement. The finely ground particles or dust particles are passed
upwardly through opening 171 near baffle 162 into chamber 144,
filtered by the filter system positioned in chamber 150 and the
finely ground or small particles come to rest as shown at 42A in
FIG. 21. When sufficient particle accumulation has occurred as
shown in FIG. 21, a plurality of doors positioned around shell 140
as shown in FIG. 3 may be opened to allow movement of the finely
ground material into chamber 186. A plurality of handles such as
handles 192, 194, and 196, allow movement inwardly as indicated by
member 198 on handle 182 and by member 202 on handle 196. Thus,
communication is established between chamber 150 into the lower
conical portion of the upper part of the vessel means 50 shown in
FIG. 3.
Positioned near the apex of the cone portion 138 is another
BIN-DICATOR or control unit 205 having vane 204 coupled to shaft
206 which extends inwardly to chamber 186. Control unit 205 acts
when the top level of product 42 passes below the rotational circle
subscribed by the outer part of vane 204 thus indicating that
chamber 186 is empty. The control unit 205 operates a microswitch
which actuates an electric solenoid air valve in panel 30 through
line 203, which air valve in turn actuates valves 126, 77, 53, 212,
and 156 to begin a new cycle of filling chamber 186 by putting the
upper portion of vessel means 50. Member 212 of valve 213 is
actuated by the change in pressure in chamber 186 thus causing
upward movement of member 212 into opening 211 to close
communication between upper chamber 186 and lower chamber 210.
Member 214 is a conical shaped solid material to support the weight
of product 42 in chamber 186 thus allowing member 212 to function
without restriction because of the weight of product 42 in chamber
186. Conduit or pipe 208 extends into chamber 210 in the lower
portion of the vessel means 50 and is in communication with member
212. Member 212 is disposed from member 214 on which product 42
accumulates when there is no communication between chamber 186 and
chamber 210. Product 42 moves downwardly along edge 215 of member
214 through opening 216 and opening 211 into chamber 210, which is
a high-pressure chamber with respect to chamber 186 in the upper
portion of the vessel means 50. Chamber 186 is subject to vacuum or
high pressure as the need arises for performing various functions.
Product 42 accumulates in the lower portion of chamber 210 and the
lower portion of chamber 210 having conical section 220 extending
from shell 140 to lower shell 224 so that material is accumulated
in the lower portion of chamber 210. Pressure blow down valve 54 is
used for relieving pressure in chamber 210 when the entire pressure
system is shut down. Thus, a conical chamber 230 is provided at the
extreme bottom of vessel means 50 known as a moisture-eliminating
device. Moisture accumulates in chamber 230 and is bled off through
pipe 232 when desired. The outlet from the vessel means 50 is at
234 with a communication conduit extending to product-metering
valve means 250 positioned in the lower portion of vessel means 50.
Valve means 250 will be explained in detail subsequently. Pipe 262
is a continuation of line 208 to provide communication to chamber
230. A communication conduit 252 extends from the valve means 250
to chamber 230 to allow the moisture-free air accumulated in
chamber 230 to be discharged through outlet 234.
The suction provided from blower 28 through line 158 of FIG. 3 goes
through chambers 160, 150, 144, and 186 into opening 132 and line
44 of FIG. 1 thereby producing incoming air through these lines and
chambers to blower 28 which allows for the movement of entrained
granular or loose products by aeration. Dense or dilute phase
pneumatic conveying principles are provided from source 40 to
vessel means 50. The relation of air to mass ratios for dry,
granular product movement regulates the amount of flow of that
product into chamber 186, in direct proportion to size of the line
44, the actual cubic foot per minute displacement of blower 28, the
amount of vacuum created in chamber 186, and the velocity created
by air movement in line 44 through inlet 132. Inlet 132 should be
of an enlarged diameter with respect to line 44 so that the
velocity of product entering vessel means 50 is reduced
substantially. As an example, a 3-inch diameter line 44 may be used
successfully with a 6-inch diameter inlet 132 to reduce the
velocity of the incoming product by 4. Abrasive products entering
lines 44 and inlet 132 into chamber 186 are moving at high
velocities as set forth in Stokes' laws and Newton's laws.
The design of the chamber 186 of vessel means 50 takes into
consideration the fact that opening 171 must be provided.
Considering the fact that the discharge angle from a nozzle
decreases along the longitudinal axis as the pressure increases so
that increased pressure provides a smaller flare at the tip of the
nozzle. As shown in FIG. 21 the lines 270 and 272 define an angle
from opening 171 that provides a reverse effect from that normally
encountered when a product leaves a nozzle. By the installation of
baffle 162 as shown in FIG. 21 the inverted conical effect of the
cone 271 defined by lines 270 and 272 is partially destroyed. The
cone 271 is produced by suction through opening 171. The inlet 132
extends into chamber 186 behind baffle 162 which is positioned
between opening 171 and inlet 132. The incoming air and product
from inlet 132 seeks an exit through opening 171, the hyperbola
described by baffle 162 in cone 271 creates a centripetal
separator. The centripetal motion extending from inlet 132 in
chamber 186 tends to flow in spiral path thus providing a level
product to be formed in chamber 186. Product 42 is brought to rest
by striking other particles in product 42 and the energy of
incoming product to chamber 186 is dissipated by expansion because
of increased volume and because of centripetal motion. Thus
accurate measurement of product may be obtained. The distance from
opening 171 to the product level control vane 184 is such that the
vertical velocity of the air moving through opening 171 allows
gravity to act upon the mass of the particles entrained in the air
stream. For example, blower 28 producing 300 cubic feet per minute
of air exhaust will produce a vacuum of 10 inches of mercury and
create a velocity of incoming air through a 3-inch line 44 of 6,800
feet per minute. The velocity is reduced to 1,700 feet per minute
in a 6-inch inlet 132 and there is a further reduction in 30-inch
diameter chamber 186 to 68 feet per minute. A velocity of 755.5
feet per minute will exist at opening 171 upon entering a 60-inch
diameter chamber 144 and the velocity of air will be approximately
15 feet per minute. When considering gravitational force on
particles attempting to rise through opening 171 it will be
appreciated that such gravitational force is substantially equal to
the upward force through opening 171. It will be noted also that
fine particles make a 90.degree. turn after entry through opening
171 into chamber 144 thereby losing velocity by gravity and then
being filtered by a plurality of filters in chamber 150 and falling
to the juncture of shell 140 and shell 136 to be injected into
chamber 186.
Product captured in chamber 186 allows the control unit 183 to
control the quantity captured by actuating valves 126 to a closed
position, valve 77 to an open position, valve 53 to an open
position, and member 256 to a closed position to stop incoming
product when vane 184 does not rotate. Chambers 186, 144, and 150
are then charged to high pressure by line 178 to equalize the high
pressure in chamber 210 thus allowing member 212 to open by gravity
and by the weight of the product. Product 42 will flow from chamber
186 to chamber 210 in such a rate as the product is being
discharged from outlet 234. When product in chamber 186 passes
below control unit 205 vane 204 rotates to provide an actuating
electrical signal. Valve 77 is closed and valve 53 is opened to
relieve pressure in chambers 150, 144, and 186 with member 212
being closed by pressure in chamber 210. By a timing device
positioned in panel 30, valve 53 is closed after pressure in
chamber 150, 144, and 186 returns to atmospheric pressure. Then
valve 126 is opened and member 256 is opened to allow product to
again enter chamber 186. The cycle continues automatically to
provide a continuous supply of product in chamber 210 to operate
under continuous high pressure. A metered uninterrupted flow of
product and air mixture continues to flow through line 16 to
distributor head and nozzle means 34 for operating upon a surface.
The product level in chamber 186 is automatically controlled by the
leveling device system to store additional product so chamber 210
is continuously supplied with product.
High-pressure chamber 210 is a product totalizer and delivery
system. Chamber 210 remains under constant high pressure while the
complete system in vessel means 50 is functioning. Product is being
moved through outlet 234 at a continuous pressure suitable to move
the product substantial distances. The kinetic energy of the
product when moved through a hose at other conduit from vessel
means 50 encounters less friction loss in such hose or conduit
thereby allowing more pressure at the point of discharge of the
product at distributor head and nozzle means 34. For example, when
the system is made operative, inlet 208 coupled to reservoir tank
24 through valve 74 shown in FIG. 2 provides pressure to chamber
210. Air simultaneously enters chamber 230 through line 262 of FIG.
3 and exits through line 252 into product-metering valve means 250.
Valve means 250 produces a venturi effect at port 281 by the
movement of air at high velocity through chamber 308 shown in FIG.
4. The pressure on the product in chamber 210 and the reduced
pressure at port 281 causes the product to flow unrestricted
through port 281 into line 266. The product 42 then mixes with the
air provided through tapered chamber 308 and the mixture of product
and air passes through line 266 and outlet 234. The distance of
shoulder 280 on member 268 from line 266 controls the size of port
281 to allow a variable mixture of product and air to be discharged
through line 266. It will be noted however that the pressure in
line 266 is substantially constant with velocity of product 42
being variable so that the amount of product discharged at the
distributor head and nozzle means 34 will vary according to the
positioning of member 294 thereby varying the size of port 281.
This feature produces a positive nonclog, constant flow of
product.
To shut down vessel means 50, valves 74, 77, and 126 are closed
from panel 30, and valves 53 and 54 are opened to relieve pressure
in chambers 186, 210, and 230.
Referring again to FIG. 4, the valve means 250 shown in FIG. 3 at
the lower portion of the vessel means 50 is presented in
cross-sectional enlarged elevational form. Pipe member 266 is
positioned above finger 268 and held in a fixed position by guide
clamp 267 coupled to support member 269. Shoulder 280 on finger 268
acts to close port 281 in pipe member 266 thereby preventing
material 42 from passing out of member 266. Product 42, it will be
remembered from viewing FIG. 3, is positioned at the bottom of the
vessel means 50 and FIG. 4 shows conical member 220 welded at 284
and 282 to shell 224. Fastening means such as screws 286 and 288
couple flange 290 to shell 224. Flange 290 includes a recessed area
292 wherein member 294 may move vertically within the limits
established by stop 296. When member 294 is moved upwardly
manually, shoulder 280 will engage member 266 to cut off flow
through chamber 282 and the stop 296 will be at the upper portion
of recess 298. Cover 300 is bolted by suitable means such as screws
302 and 304 to flange 290. Flange 290 has at its upper portion a
threaded member 306 for maintaining packing 307 in place. Finger
member 268 is threadedly coupled to member 294 and member 294 has a
tapered chamber 308 extending to elbow 264. An O-ring seal 310
prevents leakage during movement of member 294 vertically. It will
be appreciated that pressure through chamber 312 and elbow 264
passes upwardly through tapered chamber 308 through chamber 282 and
member 266 to allow air to discharge from the chamber 230 of vessel
means 50. Movement of the member 294 is actuated manually to adjust
selected amount of product flow desired at distributor head and
nozzle means 34. Thus, the valve means 250 shown in FIG. 4 acts to
allow selective discharge of material 42 through port 281 and
chamber 282 of member 266 to provide an extremely high velocity to
the product as it moves upwardly in the direction of the arrows
shown in FIG. 4. However, it will be remembered that material 42
when used for cleaning surfaces will be a granular abrasive such as
sand and care must be exercised to maintain product 42 in a mild
state of turbulence which will prevent the product from bridging
and clogging or entraining. Thus, operation is achieved by the
movement of member 294 in allowing substantial pressure buildup to
move the product 42 through chamber 282. Although high pressure is
involved, the parts specified to be used with the valve means 250
shown in FIG. 4 need not have special wear characteristics but must
be merely of durable material which will have a substantial
life.
The phenomena encountered in the present invention may be termed a
reverse-venturic effect to allow rapid filling of chamber 186 with
product 42 so that uninterrupted flow of product will occur through
vessel means 50.
One of the principal limitations with prior equipment has been the
inability to provide constant supply of product at high pressure to
supply a constant and continuous portable sandblasting operation
for cleaning surfaces. The present invention by utilizing the
structure and results obtained in vessel means 50 allow rapid
filling of the storage portion of vessel means 50 and measurement
of selected quantities to be passed into chamber 210 to assure a
continuous and uniform supply of pressurized product to pass
through distributor head and nozzle means 34. The vessel means 50
provides means, function, and result heretofore unattainable with
other vessel means which handle abrasive materials. Although known
vessels have provided high-pressure flow and movement of liquids
the circulation, movement, and abrading characteristics of abrasive
materials has not allowed utilization of such known vessels because
improper movement or motion of abrasives within the vessel would
cause breakdown, erosion, and deterioration of the vessel shell
thickness. Maintaining shell thickness is of primary importance
when operating pressure vessels because of safety requirements. It
is evident that if a vessel which is processing granular abrasives
moving at high velocity within such vessel that the vessel shell
will be subject to bombardment by the abrasive thereby causing
destruction of the shell of such vessel. In known vessels using
cyclone separator principles the circular pattern of the abrasives
causes wear on the shell of the vessel. A novel feature of the
present invention is the fact that abrasive product flow enters the
vessel means and moves downward to strike upon other abrasive
particles rather than upon the vessel shell or vessel components
thereby providing abrasive to abrasive contact instead of abrasive
to metal or other material subject to wear. The circular action of
the abrasive within vessel means 50 is by centripetal motion rather
than by centrifugal motion as in vessels known prior to the present
invention. Such known vessels act as a centrifuge instead of the
centripetal separator baffle action of the present invention.
Therefore the present invention prevents destruction of vessel
shells.
The present invention, particularly the vessel means 50, further
prevents destruction of the exterior vessel shell by locating
chamber 186 so that such chamber is not defined by the outer shell
of the vessel means 50 but is positioned in a housing within the
outer shell of vessel means 50 thus preventing wear on the outer
shell. This feature allows chamber 186 to capture the abrasive
entering the top section of vessel means 50 thus providing for
complete protection of the filter system and outer shell from
damage and wear by abrasion.
The chamber 150 or outer chamber selective product classifier and
injection system allows recovery of all fines and dust of the
abrasive conveyed into vessel means 50 to be returned without loss
of any abrasive whatsoever.
Referring again to FIG. 20, FIG. 21 and FIG. 3 it will be apparent
that movement of abrasives or other products within vessel means 50
is controlled to provide maximum pressure outlet for the metered
product upon exit from vessel means 50 while utilizing a compact
vessel having optimum baffle positions and optimum chamber shapes.
Such vessel means 50 continually supplies product to the
distributor head and nozzle means 34 by continuous action, vacuum
pressure automatic conveying.
Referring now to FIG. 5, a top plan view is shown of the trolley
means 36 of the present invention. FIG. 6 is a side, elevational
view of trolley means 36 showing the trolley means operating on a
tank 14 having a floating roof 324. Surface 14C is the portion of
tank 14 to be cleaned and guide tower means 32 is shown positioned
near surface 14C.
Pneumatic motor 84 is shown positioned on platform 326. A spool 82
containing cable 80 is shown coupled to pneumatic motor 84.
Obviously, pneumatic motor 84 provides rotation to spool 82 thereby
causing cable 80 to be moved over sheave 83. As will be explained
in detail subsequently, movement of cable 80 causes movement of the
distributor head and nozzle means along guide tower means 32.
FIG. 5 shows frame 738 as an elongated triangular structure with an
opening 342 adapted to receive guide tower means 32 with such
opening. Frame 738 may be used to support guide tower means 32.
Guide tower means 32 may be moved vertically through opening 342 to
cause movement to the distributor head and nozzle means 34 when
distributor head and nozzle means 34 is attached to guide tower
means 32. Frame 738 may be coupled to member 360 by suitable
fastening means such as a swivel bolt 730 and pins 731 and 732 as
shown in detail in FIGS. 25 and 26. With guide tower means 32
attached to member 738 and by removing pins 731 and 732 the guide
tower means 32 may be pivoted about swivel bolt 730 and positioned
at a selected angle by positioning pins 731 and 732 in holes
surrounding the swivel bolt 730. Brace members 350, 352, 354 and
356, 360 and 340 are coupled to form an adjustable boom which is
coupled between plates 326 and 327. Such boom can be moved to vary
the distance from spool 82 to guide tower means 32 by anchor bolts
371 and 373 which may be coupled to plate 326. Plate 326 may be
coupled by suitable means to angle iron members 362 and 364.
Channel members 366 and 368 are coupled to member 362 with channel
members 370 and 372 being coupled to member 364. Unit 374 which was
explained previously is also shown in FIG. 5.
Referring now particularly to FIG. 6, the trolley means of the
present invention is shown positioned on edge 390 of tank 14. It
will be remembered that tank 14 shown in FIG. 6 is of a floating
roof type wherein the roof height varies as the amount of liquid
varies inside the tank. Member 370 extends on the outer portion of
tank 14 and coupled to member 370 is member 392. Coupled to member
392 is an axle 394 having mounted thereon a roller 396. Roller 396
moves along edge 14C when the trolley moves about the periphery of
the tank. Another roller may be positioned on member 366 shown in
FIG. 5 but not shown in FIG. 6. Coupled between members 362 and 364
is a channel member 400 having attached thereto axle 402. Axle 402
has mounted thereon wheels 404 and 408 having substantially the
same diameter and a smaller wheel 406 positioned intermediate wheel
404 and 408. As shown in FIG. 6, the trolley means 36 moves on edge
390 with wheel 406 being in contact therewith while wheels 404 and
408 are not in contact with the top of the tank since the tank has
a floating top. Another set of rollers may be coupled near member
362 to provide stability and easier movement of the trolley means
36. Coupled to member 372 by suitable fastening means such as a
bolt 410, is a support member 412 having mounted thereon an axle
414 with a roller 416 moving along the inside portion of tank
surface 14C. Another roller may be coupled to member 368 to provide
stability and easier movement of the trolley means 36 on the tank.
It will be appreciated from viewing FIG. 5 and FIG. 6 that the
trolley means 36 provides support for guide tower means 32 and for
the distributor head and nozzle means 34 coupled to the guide tower
means 32, thereby supporting substantial weight. Yet trolley means
36 moves easily along the edge of the tank and is, to a large
degree, balanced in an optimum manner to prevent the trolley means
36 from falling from the tank while providing support for guide
tower means 32. Thus, trolley means 36 shown in FIGS. 5 and 6 to be
adapted for use on a floating roof tank provides support to guide
tower means 32 and further allows movement of the trolley means 36
along the tank so that surface 14C may be easily and effectively
cleaned in accordance with the present invention.
FIG. 8 is a back elevational view of part of trolley means 36 as
shown in FIGS. 5 and 6 of the present invention on a floating roof
tank showing pneumatic motor 84, spool 82, cable 80, positioned on
platform 326. Unit 374 has been described previously and is the
control unit for pneumatic motors 84 and 92. Members 362 and 364
are shown along with member 372 and member 368. Member 400 is shown
supporting axle 402, having wheels 408, 406, and 404 thereon. Wheel
408 is the only wheel visible in FIG. 8. Suitable driving means may
be coupled to the wheels supported on axle 402 and such driving
means may include a toothed gear 410 having a chain 412 positioned
thereon. Motor 92 has coupled thereon a toothed sprocket 414 so
that when motor 92 is actuated to provide rotation of sprocket 414,
chain 412 engages sprocket 410 and causes movement of the trolley
means along the upper portion of the tank 14. Edge 390 of the tank
is shown in FIG. 8 and it will be appreciated from viewing FIG. 6
that edge or lip 390 provides the area at the upper part of the
tank on which the wheels of the trolley means move. Coupled at
member 368 is axle 420, having wheel 422 and two other wheels
thereon similar to the wheel assembly associated with axle 402.
Axle 420 provides an idler support for the trolley means 36. The
operation and structure of the assembly associated with the axle
420 is substantially identical with the structure and assembly
associated with axle 402 except that the power drive means is not
coupled to the assembly of axle 420.
FIG. 7 is a front elevational view of the trolley means adapted for
use on a tank having a conical roof structure. The roof 430 of tank
14 is substantially conical in shape and at the apex of the cone a
support member may be mounted and coupled with a cable 432 to
member 372. It will be noted in FIG. 6 that member 372 extends
downwardly into the tank having a floating roof. It will be
appreciated that members 372 and 368 are adjustable to a horizontal
position to act as a ballast carrier and safety device when
utilized on a conical top tank. No tension will be present on cable
432, but cable 432 acts merely as a safety device and also aids in
keeping the trolley means at the proper location for tanks which
are "out of round." The wheel assemblies on axles 402 and 420 are
adjustable to fit the curvature of any size tank. It will be
appreciated in viewing FIG. 7 wherein the trolley means is
positioned on a fixed roof tank that the trolley means shown in
FIG. 6 is easily adaptable for use with a flat roof tank or with a
tank having a conical-shaped roof. The wheel assemblies on axles
402 and 420 are pivotal to allow inward and outward movement from
the center of a tank being cleaned and such wheel assemblies also
swivel movement about a vertical axis thus fitting any diameter of
tank having any type of roof. Guide tower means 32 is positioned in
member 738. Cable 80 passes over sheave 83 onto spool 82 coupled to
motor 84. Platform 326 supports motor 84 and spool 82. Members 372
and 368, with member 368 not being visible in FIG. 7, are extended
in the same direction as members 364 and 362 by coupling bolts 434,
436, 438, and 440. Suitable weight means or ballast is coupled on
members 372 and 368 and supported by wheel 416 on roof 430.
Weight means 442 positioned on number 372 may be a suitable
counterbalance weight for the guide tower means 32. Member 370 on
which axle 394 is positioned by member 392 allows roller 396 to
engage surface 14C of tank 14. It will be appreciated that axle 402
of assembly 400 is tilted from the vertical slightly so that large
diameter wheels 404 and 408 are on top 430 while wheel 406 rides
above top 430. The other axle assembly 420 shown in FIG. 8, but not
visible in FIG. 7, operates in substantially the same manner. Wheel
assembly 412 also is positioned slightly out of the vertical plane
to allow wheel 416, which is rotating on axle 414, to ride on tank
top 430. Wheel assembly 412, acting in conjunction with the
power-driven wheel assemblies identified as axle assemblies 402 and
420, allow the trolley means 36 to move along the conical surface
430 so that the trolley means 36 does not become unbalanced or
become overstressed. Insofar as is known to applicant, applicant is
the first to devise a commercial cleaning device capable of moving
at a uniform rate continuously over a conical surface of a fixed or
floating roof tank without danger of overstressing component parts
of the device and without danger of the entire device falling from
the tank roof.
FIG. 9 is a top plan view of the distributor head and nozzle means
34. Tank 14 to be cleaned is shown with surface 14C being bombarded
by a plurality of nozzles such as nozzle 450, nozzle 452, nozzle
454, nozzle 456. It will be appreciated when viewing FIG. 9 that
the positioning of nozzles 450, 452, 454 and 456 is such that a
fixed distance from surface 14C is maintained from the end of each
nozzle so that the distance from nozzle end 458 of nozzle 450 is
the same distance from surface 14C as nozzle end 460 of nozzle 452.
Likewise, nozzle end 462 of nozzle 454 is the same distance from
surface 14C as the other nozzles, and nozzle end 464 also is the
same distance from surface 14C even though surface 14C generally
will be a curved surface. The nozzles 450, 452, 454 and 456 are
fixedly coupled to a platform 470 having long members 472 and 474
and short members 476 and 478. Suitable coupling means identified
as 480, 482, 484, 486, 488 and 490 may be utilized in maintaining
the nozzles at a fixed distance from the surface to be cleaned. It
will be appreciated that the fastening means for the nozzles may be
of the type which allows easy setting of the nozzles for a
particular curvature tank or for a particular operation wherein a
specified finish is required on the surface to be cleaned. Such
fastening means may be remotely operated to allow remote setting
and adjustment of the nozzles and the blast pattern. Guide tower
means 32 is shown positioned in a platform 500. Platform 500 is
supported by members 502 and 504 on a carrier 506. Carrier 506
includes a side 508 and 510. Rollers 512, 514 and 516 are
positioned on the carrier to allow the distributor head and nozzle
means to be moved on guide tower means 32. As shown in FIG. 10,
additional wheels at the lower portion of the carrier are provided,
such as wheel 520 and 522, to allow stability of the carrier.
Support 524 is coupled to cable 80 so that the distributor head and
nozzle means may be pulled upwardly. Obviously, when the
distributor head nozzle means is lowered, the weight of the unit
will lower itself by gravity. Distributor head 550, shown in FIG. 9
and FIG. 10, is supported on platform 500 by support members 552
and 554 with members 502 and 504 providing support to platform 500.
Input 16 feeds pressurized abrasives to distributor head 550. Since
substantially high pressures are involved, distributor head 550 is
coupled together by a plurality of bolts such as bolts 560 and 562.
Input 16, as shown in FIG. 10, is provided on the bottom portion of
distributor head 550 with output hose 564 and 566 coupled at the
bottom portion of distributor head 550. Hoses 564 and 566 are
coupled to the nozzles. Although two hoses such as 564 and 566 are
shown in FIG. 10, it will be appreciated in viewing FIG. 9 that
since four nozzles are being utilized, four hoses similar to hoses
564 and 566 will be required. Any number of nozzles may be used
with any desired pattern of blast.
FIG. 11 is a sectional plan view of distributor head 550. Ring 570
includes a plurality of bolts 560 and 562 around the outer edge of
the distributor head 550. As explained previously, the purpose of
these bolts is to provide proper coupling to the entire assembly
since substantially high pressures are involved. 572 is the bolt
visible in FIG. 12 which is a sectional elevational view on line
12-12 of FIG. 11. A steel pipe 574 may be utilized as the principal
housing of distributor head 550 as shown in FIG. 11. Inlet 576 is
coupled to hose 16. A plurality of outputs 580, 582, 584 and 586
are positioned at substantially equal distances from the input 576
with the center portion of the outputs 580, 582, 584 and 586 being
substantially on a circle having as its center the input 576. Any
number of outlets may be used so long as material or product builds
up in hollow cylinder or pipe 574.
Referring now to FIG. 12, it will be appreciated that the inlet
from hose 16 through 576 allows abrasive material 42 to accumulate
within the distributor head 550, so that as abrasives are brought
into the distributor head 550, there is no wear on the component
parts of the distributor head since the static abrasive 42 is
formed and the abrasives entering the distributor head 550 hits
against the static abrasive. Thus, abrasives entering through inlet
16 and 576 go out through outlets 584 and 580. Steel tank 574 is
positioned between upper plate 590 and lower plate 592. A suitable
gasket, such as rubber, may be positioned at 594 around the upper
portion of ring or pipe member 574, and another rubber gasket 596
may be positioned on the lower portion of steel pipe 574. Thus, a
configuration as shown at 598 in FIG. 12 is provided when the
abrasive enters through inlet 16 and 576 and is discharged through
the various outlets 580, 582, 584 and 586 shown in FIG. 11 with
only outlets 580 and 584 being visible in FIG. 12. The static
abrasive build up occurs as the system of the present invention
begins operation, and is maintained until the system is shut
down.
FIG. 13 is a sectional elevational view of the distributor head 550
taken along line 13-13 of FIG. 11. Bolt 562 is visible showing
upper plate 590 being joined to lower plate 592. A plurality of
bolts is used to couple upper plate 590 and lower plate 592 to the
steel pipe 574. As has been explained previously, upper rubber
gasket 594 is positioned between steel plate 574 and upper plate
590 and lower gasket 596 is positioned between lower plate 592 and
steel pipe 574. Inlet 16 enters at 576 into chamber 598. The static
abrasive 42 is positioned as shown in FIG. 13. Outlets 582 and 580
are coupled to the distributor head 550 as explained previously,
and 580 and 582 are coupled to nozzles shown in FIGS. 9 and 10.
Inlet 16 may be threadedly coupled to lower plate 592, and it will
be appreciated that the distributor head positioning provides the
static abrasive pattern set forth in FIGS. 12 and 13 thereby
allowing the discharge from the distributor head to be more
effective than has been heretofore possible.
FIG. 14 is a top plan view of a nozzle 610 positioned away from a
surface such as surface 14C of a tank 14 to be cleaned. R may
indicate a radius such as the length of a man's arm with point 612
being the center and arc 614 being described by the radius R. It
will be apparent that when nozzle 610 is in position 616, for
example, that the distance 618 from the nozzle to the surface 14C
is substantially greater than the distance of the nozzle end 610
positioned for a blast pattern indicated as 620, for example.
Likewise when nozzle 610 is moved to position 622, the distance 624
from the nozzle end to surface 14C is greater than the distance
from the nozzle end to surface 14C when nozzle 610 is in the
position shown to give a pattern 620. In blasting surfaces with a
human, the distance, angle, and pattern of abrasive flow from the
nozzle will vary thereby causing a variable anchor pattern on the
surface being cleaned. The human error is compounded because of the
pivotal movement of a human at the feet, knees, shoulders, elbows,
and wrist thereby causing an erratic anchor pattern to be formed
whenever manual sandblasting is performed.
FIG. 15 is a greatly enlarged sectional view of surface 14C showing
the anchor pattern 626 obtained when a nozzle is moved as indicated
in FIG. 14. Thus, it will be appreciated from viewing FIG. 15, that
the peaks identified as 628 and 630 have small valleys 629 and 631,
when compared with peaks 634 and 636 having a valley 635 in the
portion of surface 14C nearest nozzle 610. The anchor pattern of a
surface being cleaned is very important in determining the holding
characteristics of the cleaned surface when a coating of paint or
other protective material is put on a cleaned surface.
Thus, in FIG. 16, which shows a coating of material 640 applied to
surface 14C, it is apparent that the distance from the outer edge
642 of the coating to the peak 636 is a distance identified as 644,
and such distance 644 indicates that only the wear depth 644 is
required before surface 14C is encountered thereby increasing
oxidation or other corrosion as the coating 640 is removed. The
coating 640 varies from a distance of 644 to a thickness of 644
plus 646. The protrusions of surface 14C vary from distance 648 to
a distance of 646. The average coating thickness may be set forth
as distance 650. Thus, it is apparent, when viewing FIG. 14, FIG.
15 and FIG. 16 that the anchor pattern of surface 14C varies
considerably when the nozzle angle is varied. In known methods of
cleaning a manually operated nozzle being moved by workmen will
vary distances and angles of the nozzle to the workpiece to be
cleaned, thereby providing an uneven anchor pattern which resulted
in less than optimum coating of the cleaned material after the
cleaning job had been completed. Thus, when uneven or nonuniform
anchor patterns are provided, the durability and life of the
coating on the material which has an uneven anchor pattern is
substantially lessened due to the fact that the native metal soon
will protrude through the coating at certain areas thereby
beginning the oxidation process which results in underneath erosion
of the film thus causing peeling and scaling and general
deterioration of the coating on the surface which had been
cleaned.
Referring now to FIG. 17, there is shown surface 14C with surface
14C being bombarded with a blast pattern 652 from nozzle 610. The
dotted portions of nozzle 610 are identified as position 654 and
656, indicates that distance 658 is the same for the three
positions of nozzle 610 shown in FIG. 17.
Referring now to FIG. 18, which is an enlarged sectional profile of
the peaks of surface 14C, it will be appreciated that all of the
peaks 660 have uniform valleys 662, thereby providing a uniform
anchor pattern.
Referring now to FIG. 19, coating 664, which has been put on
surface 14C, provides a constant distance 666 from the outer edge
668 of coating 664 to the peak 660 of surface 14C. Thus, the
distance 666 and the distance 670 are substantially identical
thereby providing uniform coating and adherence of coating 664 of
surface 14C. It is apparent that the wearing qualities of the
coating 664 as exemplified in FIG. 19, will be substantially
greater than the wearing pattern provided by coating 640 shown in
FIG. 16. In FIG. 19 the coating 664 has no areas where the coating
is thin to allow early contact of peaks 660 with the atmosphere
outside of coating 664. Nozzles 654, 610 and 656 are at the same
distance and striking angle to the surface regardless of the
direction of travel.
Referring now to FIG. 22, FIG. 22 shows the interior of tank 14
being cleaned with apparatus of the invention. Inner surface 14D is
being cleaned with the apparatus of the present invention mounted
on tracks 672, 674 and 676. Tracks 672, 674 and 676 are mounted on
a roller assembly 680 which includes wheels 682, 684 and 686. The
assembly 680 is in an arc form of segments to allow the guide tower
means 32 to be moved in a circle within tank 14 to maintain
distance 688 constant. It will be appreciated that by keeping the
angle of the nozzles constant and the distance 688 constant, that a
uniform anchor pattern will be provided on surface 14D of tank 14.
Nozzle 456 of the distributor head and nozzle means 34 is shown
coupled through hose 564 to the distributor head 550. Inlet 16
provides pressurized abrasive to the distributor head 550 in a
manner explained previously. Platform 500 supports the nozzles and
the distributor head 550. Rollers 520 and 522 are shown to allow
travel of the distributor head and nozzle means 34 along guide
tower means 32. Cable 80 passes over sheave 690 and over sheave
692, to the spool positioned on platform 694. It will be apparent
that the movement of the nozzle means as well as the distributor
head 550 is accomplished by rotation of spool 82 driven by motor 84
and vertical movement of platform 500 thus occurs.
In order to counterbalance the guide tower means 32 and the
equipment mounted on such guide tower means, platform 700 is
provided with weight 702 positioned on the outer portion of
platform 700 near the track or rail 676. Rail 676 is a greater
elevation from the floor than rails or tracks 672 and 674. Such
greater elevation of track 676 causes guide tower means 32 to move
toward surface 14D. However, weight 702 restrains movement of guide
tower means toward surface 14D thereby allowing track 676 to
provide a double counterbalancing effect. Brace members 704 and 706
are provided and couple platform 700 to member 708 of guide tower
means 32. Thus, in viewing FIG. 22, movement occurs along tracks
672, 674 and 676 after a section of track has been positioned by
movement of platform assembly 680. Tracks 672, 674, and 672 are
segmental so that any number of segments of track can be used
depending upon the particular need. Vertical movement of the
distributor head 550 and the nozzle platform 500 is accomplished in
the manner previously set forth wherein pneumatic motor 84 rotates
spool 82 having cable 80 thereon. The arrangement set forth in FIG.
22 provided uniform, fast, reliable cleaning of the interior of
vessels so that workmen are required inside the tank only for
positioning of platform assembly 680. The procedure of present
invention inside a tank as shown in FIG. 22 is important since
workmen may be removed from the dust hazards in the tank. Such dust
hazards result from explosion of the abrasive upon impact with the
surface being cleaned by such abrasive. Present methods for
sandblasting the interior of enclosed structures requires that
workmen work on platforms on scaffolds with airfed dust hoods and
numerous safety devices attached to such workmen. Sandblasting
creates heavy dust conditions and visibility becomes zero so that
rework becomes necessary after inspection. The heavy dust is a
health hazard to the workmen and it is impractical to exhaust all
of the dust from the interior of the structure. High temperatures
and poor ventilation result in fumes and contaminating chemicals
being present in the structure being cleaned so that the hazardous
dust and other contaminants restricts visibility of the workmen
thereby requiring the workmen to wear safety devices which are
cumbersome and dangerous in themselves. Thus it will be appreciated
that workmen cannot properly hold a nozzle discharging abrasive so
that a uniform anchor pattern is provided. The present invention
allows workmen to be removed from the interior of the structure
being cleaned while sandblasting is performed. It will be
appreciated that the abrasive source may be brought in through
conduit or coupling 16 so that abrasive storage inside the tank is
not required as has been heretofore done. The arrangement set forth
in FIG. 22 is thought to be completely novel insofar as applicant
is concerned, inasmuch as no prior art patents show or suggest in
any way any of the arrangement set forth in FIG. 22 for allowing
cleaning of the interior of tanks by remote control. Furthermore
applicant is not personally aware of any devices or methods which
anticipate the arrangement set forth in FIG. 22.
Referring now to FIG. 23, tank 14 is shown having a top or roof 430
with a surface 14E to be cleaned. The nozzle arrangement is shown
mounted on a boom 710 having counterbalance weight 712 positioned
on end 714. Cable 80 passes over sheave 716 and sheave 718, thereby
providing movement to nozzle platform 500. Intake 16 is shown with
nozzles 456 and 450. Thus, the roof 430 and the surface 14E to be
cleaned are provided with distributor head and nozzle means
movement horizontally along boom 710. It will be appreciated that
the movement is achieved substantially identically with the
movement set forth previously when cable 80 is moved. FIG. 23,
along with FIG. 22, clearly shows the apparatus of the present
invention applying the method of the present invention to achieve
uniform anchor pattern within the interior of a tank to be cleaned
with many dangers to workmen being removed.
FIG. 24 shows tank 14 having steps 14A thereon. In one modification
of the present invention guide tower means 32 may be easily moved
from a substantially vertical plane to allow the distributor head
and nozzle means 34 to be positioned under stairs or steps 14A.
Trolley assembly 36 moving on top of the tank 14 will allow the
area near stairs 14A to be cleaned properly. After the trolley
means 36 moves around the tank, the area 720 near stairs 14A may be
cleaned in a similar manner after the guide tower means 32 has been
positioned as shown in FIG. 24. It may be noted in FIG. 24 that an
obstruction such as a valve 721 may be passed over by the guide
tower means 32 and by distributor head and nozzle means 34 by
pivotal positioning of guide tower means 32 and actuation of the
trolley means 36. Also guide tower means 32 may be moved vertically
through member 738 to avoid such obstruction. Extension arms to
hold the nozzles may be attached to distributor head and nozzle
means 34 to sandblast areas immediately above such obstruction.
FIG. 26 shows the pivotal connection of the trolley frame 738
positioned on guide tower means 32. A plurality of holes, such as
hole 726, are provided around a central hole containing a suitable
fastening means 728 such as a swivel bolt. Locking assembly 732
allows guide tower means 32 to be pivotally positioned around
swivel bolt 728.
FIG. 25 is an enlarged sectional view showing locking assembly 732
which is threadedly coupled to member 340 and protrudes through
opening 748 in frame 738. Swivel bolt 728 has a nut 729 threadedly
coupled thereto. Head 742 is positioned against frame 738. Washer
736 is positioned between nut 729 and member 340. Thus, frame 738
may be rotated about swivel bolt 728 to position guide tower means
32. Thus, it is apparent that when the position of frame 738 is to
be charged, the removal of locking assembly 732 is accomplished by
removing the assembly from tapered opening 748 so that the assembly
732 may be positioned in the desired hole, such as the hole set
forth as 726 in FIG. 25. It will be appreciated that a plurality of
locking assemblies such as 732 may be utilized in a plurality of
openings. The arrangements shown in FIG. 25 and FIG. 26 to allow
positioning of guide tower means 32 and the distributor head and
nozzle means 34 as shown in FIG. 24, is easily, effectively, and
quickly accomplished to give versatility to the guide tower means
32 and the work area available to the distributor head and nozzle
means 34 is increased.
Thus, the present invention provides apparatus for moving products
at a high velocity substantial distances so that granular
abrasives, for example, may be effectively utilized in the
automatic cleaning of work surfaces such as the exterior and
interior of large storage tanks such as oil tanks, grain storage
tanks, or petrochemicals. The vessel means of the present invention
provides effective continuous flow of abrasives through the system
so that a uniform anchor pattern is provided on the area being
cleaned. In the event that the vessel means is to be utilized
merely for product transportation, such transportation can be
effected. For example, material in ships and other storage areas
may be rapidly and effectively removed with the vessel means of the
present invention. The automatic movement of the distributor head
and nozzle means of the present invention allows simultaneous
movement in both horizontal and vertical directions to obtain any
desired path. Thus the present invention provides apparatus and
methods which keep pace with recent technological developments in
the protective coating industry so that lives, money, and time are
saved. Although a preferred embodiment of the present invention has
been shown and described in accordance with the statutory mandate
of the U.S. Pat. Laws, the invention is defined by the following
claims. Although such claims may be presented in indented format to
facilitate reading and understanding thereof, such indented format
is not to be construed as a structural or functional limitation of
the elements or steps recited in such claims.
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