Not Applicable
Not Applicable
Abrasive blasting (also known as “sand blasting”) is well established in the art. Sand-sized particles are drawn from a blast pot into a blast stream of pressurized air and ejected from a nozzle of a blast hose to scour surfaces. While effective for restoring surfaces by removing the outermost layer, removing dirt, corrosion, oxides, paint, and other surface contaminants, sand blasting produces a dust that presents a health hazard for those operating the blasting equipment and others active in the vicinity. Under best is practices, pilots performing sand blasting operations are typically required to don protective clothing, including respirators to safeguard against respiratory inflammation and pulmonary diseases such as silicosis. Further, since dust is airborne, sand particulates produced at pressure into the ambient environment during sand blasting operations tend to travel farther than intended and settle to cover work areas. This requires a second round of cleaning to remove the sand particulates as well as any surface particulates that have inadvertently been airborne during scouring operations. Wet abrasive blasting is preferable to sand blasting in most instances, since use of a non-compressible fluid, such as water, maintains particulates in-stream and captures surface particulates scoured from the surface to wash away with outflow and cleaning effluents. In typical wet abrasive blasting operations, water is pumped into the blast pot along with sand-sized grit particles. The blast pot is pressurized and a slurry is introduced into a blast stream airflow for forcible ejection of the slurry out of a blast hose. Surface cleaning and scouring therefore occurs in much the same capacity as in dry abrasive blasting, however the slurry remains heavier than air and serves to capture particulates and route cleaning effluents away from the work area. This prevents formation of dust clouds and airborne particulates and provides for rinsing operations concurrent with surface cleaning, as well as operation of an alternate rinse cycle providing water to further remove slurry and cleaning effluents from the targeted surface and/or workspace. Slurry, being lubricated by the water, further decreases wear of the blast hose and its associated valves relative to dry abrasive blasting operations and, therefore, reduces frequency of replacement parts and servicing maintenance. Clearly, wet abrasive blasting is to be preferred.
The present invention, then, has been devised to enable conversion of a dry blast pot for use in wet abrasive blasting. The present dry to wet abrasive blast machine conversion kit has been devised to readily convert a dry blast pot used in sand blasting for use in wet abrasive blasting without requiring additional penetrations into the blast pot envelope whereby existing ratings (such as safety and use ratings by the American National Standards Institute (“ANSI”) or the American Society of Mechanical Engineers (“ASME”), among other professional, trade, and manufacturing regulators) may be maintained.
The present invention, therefore, provides an expedient means of converting an existing dry blast pot for use in wet abrasvie blasting with minimal alterations to the existing equipment while providing for a remote rinse cycle and manual controls controlling blasting and rinse operations by a pilot directly from the blast hose nozzle.
The present invention relates to surface cleaning operations and equipment, and particularly to a dry to wet abrasive blast machine conversion kit employable to convert existing dry blast pots for use in wet abrasive blasting operations with minimal adaptation and without compromising the structural integrity of the blast pot or voiding approved manufacturer or usage ratings and/or warranties.
The present dry to wet abrasive blast machine conversion kit and method has been provided to enable ready conversion of an existing blast pot used for dry abrasive blasting (also “sand blasting”) with minimal adaptation and without penetrating the blast pot anew whereby the structural integrity of the blast pot is ensured and applied manufacturer and usage ratings, such as ratings by the ASME and the ANSI and other trade and professional standards monitoring organizations, will not be compromised. The present dry to wet abrasive blast machine conversion kit enables a convenient means to transform existing sand blasting machines and apparatuses into preferential wet abrasive machines and apparatuses for wet abrasive blasting operations.
The present dry to wet abrasive blast machine conversion kit and method, therefore, makes use of the existing penetrations in an existing dry blast pot to enable use storing liquid under pressure and conveying a slurry to a blast stream for wet abrasive blasting operations. Internal piping used in sand blasting is removed from the interior of the blast pot. A multi-function fluid manifold is installed into the existing air pressure release aperture penetrating the blast pot. The multi-function fluid manifold includes a fluid inlet manifold, having a fluid inlet valve, by which fluid (typically water) is introducible into the pot interior when connected via a fill line to an associated water source. The multi-function fluid manifold also includes a pressure release valve to enable pressure release from the pot when necessary. The multi-function fluid manifold installs readily into the existing air pressure release aperture piercing the existing blast pot envelope without having to introduce additional penetrations in the blast pot envelope. Thus, no additional penetration of the blast pot is required to situate the multi-function fluid manifold to the blast pot for use in filling the blast pot.
The air pressure release aperture is typically situated upon blast pots proximal the top of the said pot, whereby emergency release of pressure is vented upward and away from surrounding articles and persons as may be present in the workspace. This makes installation of the multi-function fluid manifold convenient and situates the multi-function fluid manifold proximal the top of the pot. A pot pressure gauge may be included upon the multi-function fluid manifold to signal the pressure attained inside the pot to the pilot or user.
In one embodiment, the multi-function fluid manifold further includes an air purge riser disposed interiorly within the pot. The air purge riser is essentially a pipe vent projected upwardly to reach proximal an uppermost point within the blast pot interior. The air purge riser, therefore, includes an upper end disposed to project proximally to an uppermost point interior to the pot whereby air may be purged from the pot via displacement when filling the pot with fluid and when pressurizing the pot for use in blasting operations. This “high point bleed” is vitally important in evacuating unwanted air (and thus voids) from the pot interior when establishing pressure for wet air blasting.
In at least one alternate embodiment, the air purge riser may instead be incorporated into a pop-up gasket installed in the uppermost aperture of the blast pot, as will be described subsequently.
The pop us gasket is disposed to seal the pot when the pot is pressurized. Seated in an uppermost aperture extant in the blast pot, the pop-up gasket drops from the uppermost aperture when pressure inside the pot is equilibrated with ambient pressure but is prevented from falling into the pot by action of a stopper, disposed upon a shaft and projected from the pop-up gasket above the blast pot, to prevent passage into the pot interior. When the pot is pressurized, the pop-up gasket is forced to seat a plunger portion into the uppermost aperture, to effectively seal the uppermost aperture from within the pot. Thus, the pot may be filled with sand and/or grit or other particulate matter when the pot pressure is equal to the ambient pressure by pouring said particulates through the uppermost aperture. When the pot is pressurized, the uppermost aperture automatically closes by action of the pop-up gasket seating thereinto.
In the at least one embodiment wherein the air purge riser is incorporated into the pop-up gasket, the pop-up gasket also functions as the air purge to evacuate unwanted air from inside the pot during filling and when pressurizing the pot. In this particular embodiment, the air purge riser includes at least one arcuate member disposed in open communication with a vent stack disposed through the shaft of the pop-up gasket. The vent stack includes a lowermost end disposed through the pop-up gasket to project interior to the pot. The arcuate member is disposed projected from the lowermost end of the vent stack, in open communication therewith, to position an interior end in a position proximal to the uppermost point interior to the blast pot. A small block valve is disposed in operational communication with the air purge riser, which is closeable by action of a threshold pressure. Thus, air is displaced out of the air purge riser during filling of the pot and when pressurizing the pot whereby pressure interior to the pot acts upon the non-compressible fluid and particulates without encountering voids and air pockets.
A riser piping assembly is installed into an extant blast aperture disposed through the pot envelope, whereat the blast air is introduced during sand blasting operations, to serve as a drain while maintaining a desired water level interior to the pot. The riser piping assembly is a section of elbow piping disposed to project an end upwards to a height interior to the pot significant of a desired water level therein. Water is therefore drainable from the pot through the riser piping assembly, but only to a level corresponding to the height of the riser piping end interior to the pot. Thus, the water level interior the pot may be conveniently lowered to a desired height appropriate to accommodate a desired volume of grit into the pot interior whereby the water level is raised by equivalent displacement. This enables expedient refilling of the pot with a desired mixture of grit and water.
A slurry hose is connectable to an extant lowermost aperture of the blast pot whereat the blast hose is attached during dry blast operations. The slurry hose conveys slurry from the blast pot to the blast hose by way of a control panel, which control panel effectuates fill of the blast pot with water from an associated water source and controls blasting and rinsing operations, as will be described subsequently. The control panel supplies means for effectuating a first hydraulic circuit, a second hydraulic circuit, and a pneumatic circuit, as will be described subsequently.
The control panel houses means for mechanically routing fluid through each of a first hydraulic circuit and a second hydraulic circuit, for blast operations and operation of a rinse cycle, as will be described subsequently. The control panel also houses means for routing compressed air through a pneumatic circuit, for operation of the blast stream and, in at least one embodiment where such action is not effectuated electronically, establishment of a branched pneumatic control circuit to enable control between blasting operations and rinsing, as will be described subsequently.
The control panel is expediently attachable to the blast pot by means of attachment members that are, in at least one embodiment, configured to suspend the control panel from the top of the blast pot. The first hydraulic circuit supplies means for pumping water into the blast pot and from thence for introduction into the blast stream. The second hydraulic circuit enables operation of a rinse cycle, routing water without the blast pot. The pneumatic circuit forces compressed air to engage the blast stream and, in one embodiment, to provide for a control signal to control switching between said circuits.
The control panel contains mechanical pumps, valves, and actuators disposed in operational communication with manual controls remotely disposed upon a blast hose nozzle (or elsewhere remotely coupled for operative control), to enable control of said circuits to activate and deactivate the said circuits on and off, and for switching between the first and second hydraulic circuits to engage a rinse cycle remotely in lieu of blasting operations.
The panel, therefore, includes means for mechanically operating the first hydraulic circuit comprising a fill pump disposed to pump water from an associated water source into the blast pot via the multi-function fluid manifold; a fill pump check valve, to ensure unidirectional water flow into the blast pot; and a blast pump, disposed to pressurize the blast pot and force slurry through the slurry hose, through a panel slurry hose section within the control panel, for introduction into the blast stream. A slurry hose pinch valve is disposed in operational communication with the panel slurry hose section, actuated in at least one embodiment by an air pilot signal branched from the pneumatic circuit (as will be described subsequently) and controllable by the pilot operating the blast hose. The slurry hose pinch valve selectively pinches off the panel slurry hose section by action of clamp members devised to squeeze the hose closed. Since the pinch valve clamp members are situated exteriorly upon the panel slurry hose, and effectively compress the hose to cease slurry introduction into the blast stream, the clamp members never come into direct contact with the slurry stream thereby reducing wear from contact exposure to the passage of grit. The panel slurry hose section terminates at a juncture with a panel blast pipe section proximal a blast hose attachment aperture disposed exteriorly upon the control panel upon an outlet side.
Means for mechanically operating the second hydraulic circuit include the blast pump operative also in the first hydraulic circuit; a rinse shut off valve, to manually disable the rinse cycle when necessary; and a rinse water solenoid valve having an actuator disposed in operational communication with, in at least one embodiment, the air control signal operative in the pneumatic circuit, as will be described subsequently. The rinse water solenoid valve is operative to open the second hydraulic circuit whereby water from the water source is caused to flow through the second hydraulic circuit excluding the blast pot whereby water is introducible into the blast stream without slurry. As will be shown in the drawings accompanying the present disclosure, the second hydraulic circuit terminates at the panel blast pipe in a position separate from the panel slurry hose, whereby cessation of the first hydraulic circuit in preference of the second hydraulic circuit yields water from the blast hose without first having to discharge quantities of slurry remaining in the slurry hose upstream of the pinch valve. Thus, once the blast hose has been discharged of all slurry, rinse water is available upon demand. The rinse water solenoid valve is likewise operable by a pilot by manual controls disposed upon the blast hose nozzle whereby the pilot may switch between blast and rinse cycles from operative position at the blast hose nozzle.
Means for operating the pneumatic circuit include an air inlet connection aperture, disposed on an inlet side of the control panel, for attachment of an air hose to convey pressurized airflow into the panel blast pipe for conveyance to the blast hose attached at the blast hose attachment aperture on the outlet side of the panel. Compressed air is fed through an air-filter regulator to regulate the air pressure within a branch pneumatic control circuit branched from the blast stream in one embodiment of the instant invention, to enable actuation of the first and second hydraulic circuits and to control blasting and rinsing cycles.
Air conveyed through the branch pneumatic control circuit is fed through a second pneumatic control line port to a control line connected to a deadman handle upon the blast hose nozzle. Air is fed back from the deadman handle to a third pneumatic control port disposed upon the control panel. A rinse signal may be conveyed from the deadman handle to actuate the rinse water solenoid valve and engage the rinse cycle, which simultaneously actuates the slurry hose pinch valve to disable introduction of slurry into the blast stream.
It should be noted that the present disclosure contemplates an alternative embodiment wherein the branch pneumatic control circuit is replaced by an electrical circuit to effectuate the actuators controlling the rinse water solenoid valve, the slurry hose pinch valve, and to actuate and de-actuate the blast cycle electrically instead of pneumatically. For a more detailed discussion of the remote rinse control set forth herein, in both pneumatic and electrical embodiments, please see the parent patent application to this continuation-in-part application, U.S. patent application Ser. No. 16/540,798, which more fully details this novel methodology, and which is herein incorporated in its entirety by reference.
The control panel is a standalone unit that is conveniently attachable upon the blast pot by action of a pair of attachment members. The pair of attachment members enable installation of the control panel to the blast pot itself, to locate the panel proximal to the blast pot, and provide for interconnection therewith to route slurry, water, and air through each of the respective circuits the control panel enables. Interconnection of the slurry hose and the blast hose, as well as the pneumatic control lines (or, alternatively in some embodiments, electrical control lines), and the fill lines with the multi-function fluid manifold, thence enables blasting and rinsing operations drawn from slurry in the pot. Connection of the fill line to a water source enables filling of the blast pot with water.
The control panel, therefore, is readily attachable to the blast pot to enable alternative use in wet abrasive air blasting operations with minimal adaptations required. The existing blast pot is essentially used as is, subsequent removal of the internal piping used in sand blasting. No additional penetrations to the blast pot envelope are required and the retrofitting to accommodate the multi-function fluid manifold, the control panel, slurry hose, and blast hose is minimal.
Thus, has been broadly outlined the more important features of the present dry to wet abrasive blast machine conversion kit so that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated.
Objects of the present dry to wet abrasive blast machine conversion kit, along with various novel features that characterize the invention are particularly pointed out in the claims forming a part of this disclosure. For better understanding of the dry to wet abrasive blast machine conversion kit, its operating advantages and specific objects attained by its uses, refer to the accompanying drawings and description.
With reference now to the drawings, and in particular
Disposed suspended from the top rim 22 of the blast pot 20 is the control panel 100, attached to the blast pot 20 by means of a pair of attachment members 102 devised to engage to the top rim 22 of the blast pot 20. In
Also disposed upon the outlet side 300 of the control panel 100 are pneumatic control ports 312, 314, 316 for connection of control lines feeding to manual controls 604 disposed upon the deadman handle 602 of the blast hose 600. The first pneumatic control line port 312 enables connection to the deadman handle 602, to effectuate actuation of the remotely controlled rinse cycle; the second pneumatic control line port 314 enables connection to the deadman handle 602, to convey supply air thereto for engaging the rinse cycle; and the third pneumatic control line port 316 enables connection to the deadman handle 602 to convey return air therefrom, to complete the branched pneumatic control circuit. Blast hose attachment aperture 318 enables connection of the blast hose 600 proper with the panel blast pipe 402 for blasting operations.
To enable controlled drainage of a particular volume of water, suited to displacement of fluid when grit is reintroduced interior to the pot previous to blasting operations, a riser piping assembly 60 is installed in the side aperture 28. The riser piping assembly 60 includes a vertical section 62 configured to project an upper end 64 to a certain height within the pot 20 interior. The riser piping assembly 60 enables drainage of water from the pot 20 to reduce the water level therein to a prescribed depth interior to the pot 20. Thus the riser piping assembly 60 may be opened to enable drainage of the water level inside the pot 20 to the prescribed level whereby addition of grid, sand, or other particulates and/or cleaning materials may be added to a known volume calculated to displace the water level, or add to the water level, back to fill the pot 20.
The pop-up gasket 30 is also shown in
The control panel 100 is shown connected to the blast pot 20 by a slurry hose 502, disposed at the lowermost aperture 29 of the pot 20, for routing slurry into the blast stream during blasting operations.
Fill pump 420 is a double-diaphragm pump used to pump water from an associated water source (not shown) into fill line 422 to introduce water into the blast pot 20. Blast pump 424 serves to pressurize the blast pot 20 and engender the first and second hydraulic circuits for blasting operations.
Main control valve-relay 410 functions as the main on-off control for the blast air cycle. In the example embodiment depicted, the main control valve-relay 410 is a pneumatic five-port, four-way, pneumatic air pilot controlled valve with one normally-closed and one normally-open port (not shown). When the deadman remote control handle 602 is squeezed by a pilot operating the blast hose 600 nozzle, air is routed through a branch circuit via an emergency stop valve 440 to an actuator upon the main control valve-relay 410. Pressurization by airflow incident this actuator causes the main control valve-relay 410 to actuate and switch airflow from a normally-open port to a normally-closed port, thereby enabling the blast cycle, as will be described subsequently.
Airflow through the normally-closed port of the main control valve-relay 410 sends a pilot signal to a branch circuit that controls the main blast air inlet valve 404 (to activate airflow through the pneumatic circuit) and concurrently instates a pilot signal at a normally-closed port of rinse control valve-relay 414. When this normally-closed port of rinse control valve-relay 414 is closed, the air pilot signal thereat is preempted.
Airflow introduced into the control circuit is likewise fed in parallel into rinse control valve-relay 414 from air filter-regulator 428. During blast operations, airflow is directed through a normally-open port inside rinse control valve-relay 414. Airflow through the normally-open port of rinse control valve-relay 414 is directed to actuate a pinch air block valve 430 disposed in fluid communication with the main control valve-relay 410 and the pinch valve 416 operative upon the panel slurry hose section 418. When actuated, the pinch air block valve 430 opens. When the pinch air block valve 430 is open, and airflow through the main control valve-relay 410 is active through the normally-closed port therein, airflow is exhausted through a pinch valve exhaust 434 to depressurize the branch circuit controlling the pinch valve 416, thereby ensuring the pinch valve 416 is open whereby the first hydraulic circuit is enabled. Thus, blasting operations are enabled when the deadman remote control handle 602 is squeezed (or activated).
Rinse control valve-relay 414 is actuated by a pilot signal diverted thereto by action of remote rinse control valve 436 disposed at the blast hose 600 nozzle (it is contemplated as within the scope of ordinary skill that the remote rinse control valve 436 be remotely located as well). Manual action at the remote rinse control valve 436 diverts airflow into a branch circuit to pressurize an actuator actuating the rinse control valve-relay 414 to switch airflow through the rinse control valve-relay 414 normally-closed port. When the normally-closed port of the rinse control valve-relay 414 is opened by the pilot signal sent from a remote rinse control valve 436, airflow pressurizes a branch circuit controlling rinse water solenoid valve 412 that enables waterflow through the second hydraulic circuit. Concurrently, airflow is preempted from the pinch air block valve 430 by closure of the normally-open valve in the rinse control valve-relay 414, preventing airflow therethrough, which thence causes closure of the pinch air block valve 430 and prevention of exhaust from the pinch valve control circuit. The pinch valve 416 is thus pressurized and actuates to cease the first hydraulic circuit by clamping the panel slurry hose section 418 closed by engagement between clamp members 417 to prevent throughflow of fluid therethrough. The rinse cycle is now enabled.
Switching between blast and rinse cycles is therefore effective immediately by an operator or pilot switching the remote rinse control valve 436. Pressure potential at both the first and second hydraulic circuits is uninterrupted. Pressure within the pneumatic circuit is uninterrupted. Only throughflow is ceased or enabled, thereby enabling immediate switching between blast and rinsing cycles.
Release of the deadman remote control handle 602 ceases blast operations—the main control valve-relay 410 switches airflow to the normally-open port whereby the pinch valve 416 is immediately actuated to cease throughflow of the first hydraulic circuit and airflow is not fed via the normally-closed port to actuate the main blast air inlet valve 404 thereby disabling the pneumatic circuit. For a more comprehensive description of the activities of the internal components above described, please review the parent application, U.S. patent application Ser. No. 16/540,798, from which this continuation-in-part claims priority.
This application is a continuation-in-part of application Ser. No. 16/540,798 filed on Aug. 14, 2019,
Number | Name | Date | Kind |
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4517774 | Dudding | May 1985 | A |
9393672 | Eliason | Jul 2016 | B2 |
9925642 | Eliason | Mar 2018 | B2 |
10537979 | Skross | Jan 2020 | B2 |
10875151 | Grau | Dec 2020 | B2 |
20220241930 | Nguyen | Aug 2022 | A1 |
Number | Date | Country | |
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20210046608 A1 | Feb 2021 | US |
Number | Date | Country | |
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Parent | 16540798 | Aug 2019 | US |
Child | 17071521 | US |