U.S. patent application number 10/956741 was filed with the patent office on 2006-04-06 for air cannon manifold.
Invention is credited to Chris Landers, Jefferson L. Shelton.
Application Number | 20060070722 10/956741 |
Document ID | / |
Family ID | 36124382 |
Filed Date | 2006-04-06 |
United States Patent
Application |
20060070722 |
Kind Code |
A1 |
Shelton; Jefferson L. ; et
al. |
April 6, 2006 |
Air cannon manifold
Abstract
An apparatus for cleaning deposits from the interior surfaces of
an industrial vessel, such as a kiln. The apparatus utilizes an air
cannon manifold for selectively directing and venting a high volume
of pressurized fluid to any one or more of a plurality of access
ports defined in the vessel whereby the pressurized fluid is
directed at the deposits to prevent them from adhering and
accumulating on the walls of the vessel. A controller is provided
to permit selection of a desired exhaust port for directing the
pressurized fluid to the access ports and for sequencing an inlet
valve in cooperation with a desired exhaust port.
Inventors: |
Shelton; Jefferson L.;
(Jacksonville, AL) ; Landers; Chris; (Anniston,
AL) |
Correspondence
Address: |
SMITH, GAMBRELL & RUSSELL, LLP
1230 PEACHTREE STREET, N.E.
SUITE 3100, PROMENADE II
ATLANTA
GA
30309-3592
US
|
Family ID: |
36124382 |
Appl. No.: |
10/956741 |
Filed: |
October 1, 2004 |
Current U.S.
Class: |
165/95 ;
124/65 |
Current CPC
Class: |
F41B 11/87 20130101;
F28G 1/166 20130101 |
Class at
Publication: |
165/095 ;
124/065 |
International
Class: |
F28G 1/12 20060101
F28G001/12; F41B 11/00 20060101 F41B011/00 |
Claims
1. An air cannon manifold comprising a housing defining a plenum
therein, an inlet port defined in a wall of said housing, said
inlet port receiving a pressurized fluid source in communication
with said inlet port, an inlet valve selectively positionable to
open and close said inlet port, a plurality of exhaust ports
defined in said wall of said housing, and a plurality of exhaust
valves selectively positionable to open and close said exhaust
ports, whereby said pressurized fluid may be communicated via said
exhaust ports and exhausted to a selected access port in a vessel
to be cleaned of deposits.
2. The air cannon manifold of claim 1 wherein said housing is
substantially boxlike.
3. The air cannon manifold of claim 1, wherein said housing is
substantially spherical.
4. The air cannon manifold of claim 1 wherein said inlet valve
further comprises an inlet valve actuator attached to said housing,
said inlet valve actuator having an extensible inlet actuator
shaft, and an inlet valve seal attached to a distal end of said
actuator shaft, wherein said inlet actuator shaft urges said inlet
valve seal in sealing engagement with said inlet port.
5. The air cannon manifold of claim 4 wherein said inlet valve
actuator is attached to an external wall of said housing, and said
inlet actuator shaft is extensible through an inlet actuator bore
defined in said housing.
6. The air cannon manifold of claim 4, wherein said inlet valve
seal further comprises a disk portion, extending from and coaxial
with a chamfered disk portion, said disk portion having a diameter
smaller than said chamfered disk portion.
7. The air cannon manifold of claim 6, wherein said disk portion
has a diameter les than an inner diameter of said inlet port.
8. The air cannon manifold of claim 7, wherein an outer surface of
said chamfered disk portion is comprised of a resilient
material.
9. The air cannon manifold of claim 1 wherein said exhaust valve
further comprises an exhaust valve actuator attached to said
housing, said exhaust valve actuator having an extensible exhaust
actuator shaft, and an exhaust valve seal attached to a distal end
of said actuator shaft, wherein said exhaust actuator shaft urges
said exhaust valve seal in sealing engagement with said exhaust
port.
10. The air cannon manifold of claim 9 wherein said exhaust valve
actuator is attached to an external wall of said housing, and said
exhaust actuator shaft is extensible through an exhaust actuator
bore defined in said housing.
11. The air cannon manifold of claim 9, wherein said exhaust valve
seal further comprises a disk portion, extending from and coaxial
with a chamfered disk portion, said disk portion having a diameter
smaller than said chamfered disk portion.
12. The air cannon manifold of claim 11, wherein said disk portion
has a diameter less than an inner diameter of said exhaust
port.
13. The air cannon manifold of claim 11, wherein an outer surface
of said chamfered disk portion is comprised of a resilient
material.
14. The air cannon manifold of claim 1 further comprising a
controller, wherein said controller provides a signal to said inlet
valve and said exhaust valve and said inlet valve and exhaust valve
are selectively positionable responsive to said signals.
15. The air cannon manifold of claim 14, wherein said controller
provides said signal at timed intervals.
16. The air cannon manifold of claim 14, wherein said controller
provides said signal responsive to a process variable.
17. A method of controlling an air cannon manifold associated with
a kiln, said air cannon manifold comprising a housing defining a
plenum therein, an inlet port defined in a wall of said housing,
said inlet port receiving a high volume pressurized fluid from a
reservoir communicating with said inlet port, an inlet valve
selectively positionable to open and close said inlet port, a
plurality of exhaust ports defined in said wall of said housing,
and a plurality of exhaust valves selectively positionable to open
and close said exhaust ports, said method comprising the steps of:
a. closing said inlet valve to seal said inlet port, b. charging
said reservoir with a high volume of pressurized fluid, c. opening
an exhaust valve of a selected exhaust port, d. opening said inlet
valve to vent a portion of said high volume pressurized fluid from
said reservoir through said air cannon manifold.
18. The process of claim 17, further comprising the step of
interrupting fluid flow to said reservoir while closing said inlet
valve.
19. The process of claim 17, wherein the step of closing said inlet
valve further comprises signaling said inlet valve to maintain said
seal for a specified time.
20. The process of claim 17, wherein the step of opening an exhaust
valve, further comprises signaling said exhaust valve to remain
open for a specified time.
21. The process of claim 17, wherein the step of opening said inlet
valve further comprises signaling said inlet valve to close after a
specified time.
22. A method of controlling an air cannon manifold associated with
an industrial apparatus having a plurality of access ports for
cleaning said apparatus by use of pressurized fluid, said air
cannon manifold comprising a housing defining a plenum therein, an
inlet port defined in a wall of said housing, said inlet port
receiving a high volume pressurized fluid from a reservoir
communicating with said inlet port, an inlet valve selectively
positionable to open and close said inlet port, a plurality of
exhaust ports defined in said wall of said housing in fluid
communication with said access ports, and a plurality of exhaust
valves mounted to said manifold and selectively positionable to
open and close said exhaust ports, said method comprising the steps
of: a. closing said inlet valve to seal said inlet port, b.
charging said reservoir with a high volume of pressurized fluid, c.
opening an exhaust valve of a selected one of said plurality of
exhaust ports, d. opening said inlet valve to vent a portion of
said high volume pressurized fluid from said reservoir through said
air cannon manifold, and, e. iteratively repeating said sequence to
vent said pressurized fluid through additional selected ones of
said plurality of exhaust ports.
23. The method as defined in claim 22 wherein said plurality of
exhaust ports are normally closed during charging of said
reservoir.
24. The method as defined in claim 22 wherein said each of said
plurality of exhaust ports are sequentially individually opened
during subsequent iterations to provide cleaning to different
regions of said industrial apparatus.
25. The method as defined in claims 22 wherein said industrial
apparatus is monitored for conditions indicating desirability of
fluid cleaning and said monitoring is used to selectively open said
exhaust ports.
Description
FIELD OF THE INVENTION
[0001] The instant invention relates to air cannons used for
cleaning and preventing the buildup of deposits on the walls of
industrial vessels, such as kilns used in the cement and paper
industries. More particularly, the instant invention relates to a
manifold for selectively directing the blast from an air cannon to
any one of a plurality of ports of an industrial vessel for
removing and preventing the build up of material deposits
therein.
BACKGROUND OF THE INVENTION
[0002] In industrial vessels, such as cement, wood or paper kilns,
and their associated structures, the accumulation of particulate
deposits on the inner linings of these vessels is a recurring
problem. Buildup of deposits in areas such as preheater and riser
ducts can choke off feed pipes and cyclones and greatly affect the
efficiency and production performance of the vessel, even to the
point of causing unscheduled shutdowns. If deposits are permitted
to accumulate the high temperatures typically encountered in
vessels, such as kilns, will cause the deposits to become encrusted
on the kiln's interior surfaces. The precise characteristics of the
buildup in these vessels may vary from plant to plant, the process
employed, and can even vary from hour to hour within the same plant
or process.
[0003] Usually, the buildup begins sticking to the walls of the
vessel lining with the consistency of talcum powder. Routine
cleaning of the deposits is a preferred method of addressing the
problem such that the deposits are removed before significant
accumulation and encrustation occurs.
[0004] Air cannons have long been an accepted method for routine
cleaning of vessel walls and maintaining material flow in many
industrial applications. While there are many different
configurations of air cannons, the principle of operation for all
air cannons is the same. A large volume of air is exhausted in a
short period of time through a access port in the vessel wall,
creating a powerful burst of air which dislodges particulate
material that has adhered to the internal wall of the vessel. The
various configurations of air cannons are generally differentiated
based on their air discharge velocity and the design of the inlet
seal for the associated air reservoir. However, each of the various
air cannon configurations in use utilize a separate air reservoir
as part of an air cannon attached to the particular vessel access
port. This configuration poses many problems to those in the
affected industries.
[0005] The first concerns the installation costs associated with
independently mounted air cannons. For each air cannon in the
system, a separate air reservoir incurs the added cost of
purchasing and maintaining the reservoir as well as installation
costs associated with routing the necessary air lines to charge
each reservoir and additional wiring activate the individual air
cannons. In some instances, attempts to avoid these installation
costs have been made whereby an air cannon assembly is moved from
access port to access port to clean the respective areas of the
vessel. While saving on installation costs, this practice incurs
its own costs in that an employee is required to reposition the air
cannon to a desired access port.
[0006] A second concern is the space requirements for installing
and operating individual air cannons with an integrated air
reservoir. Traditional air cannons with their individual air
reservoirs require a substantial amount of space to install and
once installed they present an obstacle for the operators working
around the particular vessel.
[0007] Third, the typical air cannon is mounted in close proximity
to the vessel, and most are mounted directly to the vessel. Usually
the processes within the vessel generate a substantial amount of
heat and considerable particulate debris. In these harsh
environments, traditional air cannons frequently experience
premature wear and failure of internal components, particularly in
its valve assemblies.
[0008] In many instances the valves used to control the flow of air
from the reservoir require the maintenance of a pressure
differential within the valve body. In order to maintain this
pressure differential within acceptable tolerances, the rate at
which the reservoir may be charged is restricted such that
subsequent firing of the cannon is delayed considerably. Moreover,
because the restriction in the reservoir's charging rate,
exacerbates the deleterious effects of any leaks which may be
present in the system.
SUMMARY OF THE INVENTION
[0009] The air cannon manifold of the present invention addresses
these problems in the industry by providing an air cannon manifold
that permits a plurality of access ports to be serviced by a single
air reservoir, providing a reliable cost effective solution to the
aforementioned problems. First, it reduces installation costs by
eliminating the requirement for a separate air reservoir at each
air cannon portal. By eliminating the requirement for a separate
air reservoir, additional savings are realized at initial
installation by eliminating the requirement to install a separate
air line to charge each separate air reservoir.
[0010] Second, by eliminating the requirement for an individual air
reservoir at each air access port, the initial space requirements
may be reduced for new installations employing the air cannon
manifold of the present invention. Similarly, modification of
existing installations to incorporate the air cannon manifold will
permit reclamation of valuable work space previously occupied by
the individual air reservoirs servicing the existing air cannon
ports. In both instances, obstructions in close proximity to the
vessel are eliminated, permitting workers around the vessel a safer
work environment.
[0011] Third, the air cannon manifold of the present invention
further permits the working components of the system, such as its
valves and sensors, to be positioned away from the high
temperatures and debris generated by the vessel, resulting in
improved reliability and extending the service life of the
components and the system.
[0012] Finally, the air cannon manifold of the present invention
enables rapid charging of the reservoir to permit a single
reservoir to service a plurality of cleaning ports or to permit
successive firing into any selected cleaning port.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The system and methodology of the present invention are
depicted in the accompanying drawings which form a portion of this
disclosure and wherein:
[0014] FIG. 1 is a perspective view of an air cannon manifold and
an air reservoir;
[0015] FIG. 2 is a side view of an air cannon manifold;
[0016] FIG. 3 is a perspective view of the air cannon manifold from
an input side, with an actuator removed to show an exhaust actuator
bore;
[0017] FIG. 4 is a partial sectional view of an exhaust valve;
[0018] FIG. 5 is a partial sectional view of an inlet valve;
[0019] FIG. 6 is a partial sectional view of an inlet valve and
exhaust valve in their open position;
[0020] FIG. 7 is a schematic diagram for sequentially selecting an
exhaust port to be serviced by the air cannon manifold; and
[0021] FIG. 8 is a schematic diagram for monitoring and signaling
alarm conditions of the air cannon manifold.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] Referring to the drawings for a clearer understanding of the
invention, it may be seen that a preferred embodiment of the
invention contemplates a single air reservoir 11, providing a high
volume pressurized air source for an air cannon system, connected
to the air cannon manifold 10 via an inlet duct 12 attached to an
inlet port 20. A plurality of exhaust ducts 13 interconnect exhaust
ports 30 of the air cannon manifold 10 with the access ports of an
industrial vessel, such as a kiln and its associated
structures.
[0023] The air cannon manifold 10 may be seen in greater detail in
FIGS. 2-6. As depicted, air cannon manifold 10 comprises a housing
14, defining a plenum therein. An inlet port 20 extends through a
first wall 15 in housing 14 and receives high volume pressurized
air from a source such as a pressurized air reservoir 11 via an
inlet duct 12, such as the elbow connector shown in the drawings.
Inlet duct 12 may be a pipe or similar conduit and may be bolted to
manifold 10 through a flange 17, or any suitable attachment means.
An inlet valve 21 is provided to control the flow of air from
reservoir 11 to manifold housing 14 by selectively opening and
closing inlet port 20.
[0024] In the embodiment shown, inlet valve 21 is best seen in
FIGS. 5 and 6, and comprises an inlet valve actuator 22, such as a
pneumatic cylinder or the like attached to second wall 16 of
manifold housing 14 an adapter plate 18 and opposing inlet port 20.
An inlet actuator shaft 23, is extensible through an inlet actuator
bore 24 defined in the second wall 16 of manifold housing 14 and
closed by plate 18. An inlet valve seal 25 is attached to a distal
end of inlet actuator shaft 23, and is selectively positioned by
inlet valve actuator 22 for sealing engagement with an inlet seat
26, defined on an interior face of first wall 15. Preferably inlet
actuator bore 24 will be dimensioned to be larger than inlet valve
seal 25, to facilitate removal of inlet valve 21 for servicing or
replacing this component.
[0025] Air cannon manifold 10 further defines a plurality of
exhaust ports 30 in a second wall 16 of housing 14. Exhaust ducts
13 are connected to exhaust ports 30 to communicate the high volume
air released into the manifold 10 to a corresponding access port in
vessel. Exhaust ducts 13 may be a pipe or similar conduit and may
be bolted to manifold 10 through an exhaust flange 18, or any
suitable attachment means. An exhaust valve 31 is provided for each
exhaust port 30 to control the flow of air delivered by manifold 10
to a desired access port in vessel serviced by the air cannon.
Exhaust valves 31 are selectively positionable to open and close
their associated exhaust ports 30. As best depicted in FIGS. 4 and
6, exhaust valves 31 comprise an exhaust valve actuator 32, such as
a pneumatic cylinder, attached to housing first wall 15 and
opposing their respective exhaust ports 30. An exhaust actuator
shaft 33, is extensible through an exhaust actuator bore 34 defined
through first wall 15. Exhaust valve seals 35 are attached to the
distal ends of exhaust actuator shafts 33 and are selectively urged
against exhaust port seats 36 by exhaust valve actuators 32. As
with the inlet valve 21, exhaust actuator bore 34 is preferably
dimensioned to be larger than exhaust valve seal 35 to facilitate
removal of exhaust valves 31 for servicing or removal of these
components. A protective ring 43 may also be attached to an inner
surface of first wall 15 coaxial with actuator bore 34, and
extending inwardly therefrom, such that upon opening of exhaust
valve 31, exhaust valve seal 35 may be retracted into ring 43 to
avoid exposure to the high velocity air experienced within housing
14 upon opening inlet valve 21. Each exhaust valve 31 is
independently controllable to permit selective routing of the air
blast to a desired access port in the vessel to clean the
respective areas of the vessel walls based on the vessel's
operating conditions.
[0026] We have found a preferred configuration for inlet seal 25
and exhaust seals 35. According to our preferred embodiment, shown
in FIGS. 4 and 6, seals 25 and 35 comprise a disk portion 41,
extending from and coaxial with a chamfered disk portion 42.
Cylindrical disk portion 41 has a diameter smaller than that of the
inner diameter of the respective inlet port 20 or exhaust port 30
to facilitate positive alignment of the seals 25, 35 in the
respective ports 20, 30. The chamfered disk portion 42 has a
diameter greater than disk portion 41, and provides for sealing
engagement with the respective valve seat 26, 36. More preferably,
chamfered portion 42 is made of a resilient material to improve its
sealing engagement as it is urged against the valve seat 26,36.
[0027] Our preferred embodiment inlet actuator 22 and exhaust
actuator 32 are mounted with their operative mechanisms external to
manifold housing 14. This arrangement provides the advantage of
permitting ready access to the actuators 22, 32 for routine
inspection, maintenance and servicing. This arrangement also
provides an advantage in that the positioning of the operative
mechanisms avoids exposure to the large pressure differentials
encountered within manifold housing 14 during cannon firing
sequences.
[0028] Having thus described an exemplar of our air cannon
manifold, its preferred method of operation will be described. A
typical single duty cycle, for the air cannon manifold comprises
the steps of sealing inlet port 20, charging the air reservoir 11
with air from a pressurized air source, opening a desired exhaust
port 30, and opening inlet port 20 to permit venting of the
pressurized air form reservoir 11 to the desired access port on the
vessel to be cleaned. This process may be controlled either
manually or automatically. A schematic diagram for a controller 50
directing sequential firing of a three port air cannon manifold is
shown in FIG. 7.
[0029] As may be seen in FIG. 7, the sequential firing cycle is
initiated at II, which initiates an air reservoir 11 charging
cycle, B02 through Q6, and exhaust port 1 activation cycle, B09
through Q2. The exhaust port 1 activation cycle delays opening of a
first exhaust valve 30 (normally closed) for sufficient time to
permit completion of the air reservoir 11 charging cycle. It should
be noted that by maintaining the exhaust valves 30 in the normally
closed position we can significantly reduce the deleterious effects
of any back draft from the vessel that may carry particulates or
high temperature air into manifold housing 14. Once sufficient time
has elapsed to charge air reservoir 11, the first exhaust valve 30
is activated and is held open for a sufficient duration to permit
completion of the inlet valve firing sequence, B04 through Q1. Upon
activation of the inlet valve firing sequence, inlet valve 20 is
opened, permitting the rapid venting of the pressurized air in air
reservoir 11 through air cannon manifold 10, first exhaust port 30
and its associated exhaust duct 13, to the desired access port on
the vessel to be cleaned. Completion of the first exhaust valve 30
activation sequence Q2, resets the air reservoir charging sequence
and initiates activation of the cycle for a second exhaust port 30,
which proceeds in like manner to that described for the first
exhaust port cycle. It varies from the first exhaust port cycle in
that signal Q3 resets the first exhaust port cycle so that first
exhaust valve 30 is maintained in a closed position. A third
exhaust port 30 is activated in like manner and restarts the
sequenced firing cycle.
[0030] We have found that when a pneumatic actuator is used for the
inlet valve actuator 22 and that actuator is reliant on the same
air source that is used to charge reservoir 11 it is desirable that
the charging of reservoir 11 be delayed while inlet valve 21 is
being closed to ensure that sufficient pressure is available to
reliably activate inlet valve actuator 22 for sealing inlet port
20. This may be accomplished by temporarily closing a valve to
block the communication of the pressurized air source to reservoir
11 for sufficient time to permit the closure of inlet valve 21. The
temporary interruption of airflow to reservoir 11 also facilitates
alignment of inlet valve seal 25 as residual air flow through inlet
port may cause misalignment of inlet valve seal 25.
[0031] Automatic control of the air cannon manifold 10 may also be
provided by monitoring process specific variables, such as
temperature, oxygen content, or the like, that would indicate
particulate accumulation at any particular location within the
process vessel. In this circumstance, the blast cannon manifold
controller 50 would be specifically targeted to remedy particulate
accumulations based on the indications of the particular process
specific variable, thereby improving the efficiency and efficacy of
the blast cannon system in maintaining the cleanliness of the
process vessel.
[0032] In addition, as shown in FIG. 8, the blast manifold
controller 50 may also provide notification of user determined
alarm conditions within the air cannon manifold 10 or air cannon
system or vessel process that may potentially impact the safety or
efficiency of the process for which the air cannon is employed.
[0033] It is to be understood that the form of the invention as
shown herein is a preferred embodiment thereof and that various
changes and that modifications may be made therein without
departing from the spirit of the invention's scope as defined in
the following claims.
* * * * *