Patent Application
20180207769
Blasting systems in the surface preparation industry generally use dry, wet, slurry, vapor abrasive, or ultra-high pressure water blast technologies to remove dirt, paint, or rust from a substrate. Vapor blast systems use a mixture of air, water, and an abrasive media—such as garnet or walnut shells—to provide the desired surface treatment. Vapor blast systems often include a pump and a pressure vessel containing an abrasive media having a density greater than water. Pumping water to the pressure pot pressurizes it and allows the abrasive media and water to mix. The pressurized media and water mixture is then plumbed into a conduit of a high flowing air stream to mix the two streams before expelling the mixture from a hose and nozzle. To ensure that the media and water mixture can be injected into the high flowing air stream, the pressure inside the pressure pot must be higher than the pressure in the air stream. Existing designs need the user to set the pressure in the air stream and to set the pressure in the pressure pot. Users typically set a desired air stream pressure and then have to set the pressure pot pressure. If the differential is too low, there will be no influx of the media and water mixture into the air stream, or there could be a back lux of air into the pressure pot.
According to an aspect of the disclosure, a blasting system includes a pressure vessel, a water line extending from a water source and connected to the pressure vessel, a water pump disposed on the water line, a water regulator disposed on the water line, and a blast line. The pressure vessel is configured to house a blast media and water mixture. The water line provides water to the pressure vessel. The water pump drives a flow of water from the water source to the pressure vessel. The water regulator is configured to receive the flow of water and to output a pressure regulated water flow having a regulated flow pressure. The regulated flow pressure pressurizes the pressure vessel to a pressure vessel pressure. The blast line conveys a compressed air flow at an air pressure, and the compressed air flow is configured to receive a flow of the media and water mixture from the pressure vessel. The pressure vessel pressure is greater than the air pressure.
According to another aspect of the disclosure, a method of blasting a substrate with a media includes regulating a water flow pressure with a water regulator to generate a regulated water flow, pumping the regulated water flow to a pressure vessel to pressurize the pressure vessel to a pressure vessel pressure having a fixed pressure point, compressing an air stream to a blast pressure and flowing the air stream through a blast line and to a blasting apparatus, and flowing media and water from the pressure vessel and into the air stream within the blast line and applying the combined flow of media, water, and air to a substrate. The blast pressure is within a range between a minimum blast pressure and a maximum blast pressure. The fixed pressure point is greater than the maximum blast pressure.
According to yet another aspect of the disclosure, a vapor blast assembly includes a pressure vessel mounted to a support structure, an enclosure mounted to the support structure, and a water regulator disposed within the enclosure and configured to generate a regulated water flow. The enclosure is configured to receive a flow of compressed air from a compressed air source, to receive a flow of water from a water source and to provide the regulated water flow to the pressure vessel, to receive a combined flow of media and water from the pressure vessel, and to output a combined flow of compressed air, water, and media. A regulated water flow pressure maintains a pressure vessel pressure above a compressed air pressure such that a pressure differential between the pressure vessel pressure and the compressed air pressure drives the combined flow of media and water into the flow of compressed air to generate the combined flow of compressed air, water, and media.
Air supply line 14 extends from compressor 12 and receives compressed air from compressor 12. System line 16 extends from air supply line 14 and to water pump 20 to provide compressed air to water pump 20 to power water pump 20. Manifold line 18 extends from air supply line 14 and to blast line 38. Blast line 38 extends from manifold line 18 and to applicator 40. Water inlet line 24 is connected to water pump 20. Water pump 20 is also connected to pumped water line 26 and drives water downstream through water regulator 22 and pumped water line 26. Water regulator 22 is connected to pumped water line 26, and pumped water line 26 extends to selector valve 28. Pressurizing line 30 and accessory line 32 extend from selector valve 28. Accessory line 32 extends to an accessory, such as a rinse hose. Pressurizing line 30 extends from pumped water line 26 and to pressure vessel 34. Media line 36 extends from pressure vessel 34 and intersects manifold line 18.
Pressure vessel 34 contains a blast mixture, comprised of media and water, which is applied to a substrate to remove a coating from the substrate and to condition the substrate for future coating applications. The media may be of any suitably abrasive material such as walnut shells, crushed glass, garnet, or any other heavier-than-water particulate, and may be applied to any desired substrate, such as wood, concrete, and steel, to clean the substrate. Compressor 12 provides compressed air to air supply line 14. A blasting air portion of the compressed air flows through manifold line 18, downstream past the intersection of manifold line 18 and media line 36, and through blast line 38 to applicator 40. A system air portion of the compressed air flows through system line 16 and is provided to water pump 20. The system air portion of the compressed air flows through system line 16 and to water pump 20 to power water pump 20. Water pump 20 draws water from a water source (not shown) through water inlet line 24 and drives the pumped water flow downstream through pumped water line 26. The pumped water is driven through water regulator 22 and continues downstream through pumped water line 26 and to selector valve 28. While water regulator 22 is shown downstream of water pump 20, it is understood that water regulator 22 may be at any desired position downstream of water pump 20 and before pressure vessel 34, such as on pumped water line 26 between water pump 20 and selector valve 28 or on pressurizing line 30 downstream of selector valve 28.
Water regulator 22 regulates a water pressure of any water pumped downstream of water pump 20 through water regulator 22. As such, water pump 20 draws water through water inlet line 24 and pumps the pumped water downstream at a pumped water pressure higher than a maximum blast air pressure required for vapor blast system 10 operation. Water regulator 22 generates a regulated water flow, having a fixed water pressure, such that a pressure downstream of water regulator 22 is fixed. The regulated water flow flows downstream from water regulator 22 through pumped water line 26 and to selector valve 28. Selector valve 28 directs the regulated water to pressurizing line 30 and accessory line 32. Accessory line 32 provides the regulated water to an accessory, such as a rinse hose. Pressurizing line 30 provides the regulated water to pressure vessel 34.
The regulated water enters pressure vessel 34 through pressurizing line 30. Because the regulated water has the fixed water pressure flowing the regulated water to pressure vessel maintains a fixed pot pressure within pressure vessel 34. When applicator 40 is triggered, the blast mixture disposed within pressure vessel 34 exits pressure vessel 34 through media line 36, and flows through media line 36 to manifold line 18. When applicator 40 is triggered, the blast mixture enters manifold line 18 through media line 36 and is combined with the blast air portion in manifold line 18 to generate an applicator flow. The blast air portion carries the blast mixture downstream to blast line 38, and downstream through blast line 38 to applicator 40. The applicator flow is then accelerated through applicator 40, such as by flowing the mixture through a nozzle, and applied to a substrate. The media impacts the substrate and is configured to remove material, such as paint, from the substrate and to condition the substrate for subsequent application of material to the substrate.
During operation, media and water are loaded into pressure vessel 34 to generate the blast mixture, and pressure vessel 34 is sealed. Compressor 12 is activated, and the system portion of compressed air flows to water pump 20 through system line 16 to power water pump 20. With water pump 20 powered, water pump 20 drives the pumped water downstream through pumped water line 26 and water regulator 22, and water regulator 22 outputs the regulated water flow. The regulated water flow flows downstream to selector valve 28, and selector valve 28 directs the regulated water flow through pressurizing line 30 and into pressure vessel 34. Because the regulated water flow has a fixed water pressure, the fixed water pressure pressurizes pressure vessel 34 to a fixed pot pressure, with the fixed pot pressure being controlled by the fixed water pressure.
With pressure vessel 34 loaded and pressurized, applicator 40 is triggered and air supply line 14 is able to provide the blast air portion of compressed air to manifold line 18. Because the fixed pot pressure is greater than the maximum blast air pressure, the blast mixture exits pressure vessel 34 through media line 36 and flows to manifold line 18. In addition to opening air supply line 14, triggering applicator 40 causes media line 36 to open such that the blast mixture may flow from pressure vessel 34 and to manifold line 18 through media line 36. A pressure differential between the blast air portion flowing through manifold line 18 and the fixed pot pressure causes the media and water mixture to flow from pressure vessel 34 and into manifold line 18. To ensure that vapor blast system 10 operates correctly, the pressure differential must be maintained such that the fixed pot pressure is higher than the blast air pressure. If the pot pressure is below the blast air pressure, then the blast mixture would be prevented from entering manifold line 18 due to the higher blast air pressure. When applicator 40 is applying the blast mixture, the regulated water continues to flow to pressure vessel 34 to maintain a pot pressure above the blast air pressure. With applicator 40 triggered, the pot pressure will drop to a level proximate the blast air pressure, but the regulated water continues to flow to pressure vessel 34 to replace the blast mixture flowing out of pressure vessel 34 and to continue pressurizing pressure vessel 34. As such, the regulated water maintains the pot pressure higher than the blast air pressure regardless of the level that the blast air pressure is set.
When applicator 40 is deactivated, the blast air portion is prevented from flowing to manifold line 18 and the blast mixture is also prevented from flowing to manifold line 18. With media line 36 closed and water pump 20 continuing to pump water, the pot pressure rises to the fixed pot pressure, because water regulator 22 continues to supply the regulated water to pressure vessel 34. Once the pot pressure reaches the fixed pot pressure, the pressure downstream of water regulator 22 will cause internal components of water regulator 22 to shift to prevent the pot pressure from continuing to rise. Water regulator will then allow additional flow when the pot pressure drops due to applicator 40 being triggered.
Water regulator 22 maintains the fixed pot pressure higher than the maximum blast air pressure. In addition, water regulator 22 maintains the pot pressure greater than the operational blast air pressure during operation. Water regulator 22 may be set to output regulated water at a fixed water pressure point, dependent on the dimensions and particular arrangement of the components of vapor blast system 10, such that the fixed water pressure point is always higher than the maximum blast air pressure. More specifically, water regulator 22 is configured to maintain the fixed pot pressure safely above the maximum blast air pressure, and to maintain the pot pressure above the blast air pressure during operation. In this way, water regulator 22 thereby ensures that the pressure differential causes the blast mixture to flow into manifold line 18 from pressure vessel 34.
Water regulator 22 maintaining the fixed pot pressure provides significant advantages. Utilizing water regulator 22 eliminates a step in the setup process, whereby the user was required to set the pot pressure and compare the pot pressure against the blast air pressure to discern whether the differential was sufficient. Water regulator 22 instead ensures that the pot pressure will be sufficiently high for vapor blast system 10 operation, thereby allowing the user to set the desired blast air pressure without being concerned about the pot pressure and eliminating potential user error and a time-consuming step. Moreover, positioning water regulator 22 downstream of water pump 20 further eliminates user misconceptions, as water regulator 22 will dampen any pressure fluctuations that may occur due to water pump 20 changing stroke or the inherent differential between an upstroke and a downstroke. As such, water regulator 22 further provides a consistent blast mixture flow, because the pot pressure will be maintained at a steady pressure throughout the blasting process. Providing a steady blast mixture flow increases the consistency of the blast pattern, which improves the consistency of the surface finish created by the media blasting on the substrate. Water regulator 22 also thereby eliminates misconceptions of poor blasting performance due to the user observing natural fluctuations in the pot pressure and interpreting the fluctuations as malfunctions or errors. Instead, water regulator 22 maintains the pot pressure at a steady pressure relative to the blast pressure during blasting, and at the fixed pot pressure when vapor blast system 10 idles.
Pressure vessel 34 and enclosure 44 are mounted to frame 42. Fill inlet 50 extends from a top of pressure pot 48. Media inlet port 72 extends into enclosure 44 and is configured to receive a blast mixture flow from media line 36. Media line 36 extends between media outlet port 52 and media inlet port 72 and connects pressure vessel 34 and enclosure 44. Pot pressure gauge 46 is disposed between pressure vessel 34 and enclosure 44, and the regulated water flows through pot pressure gauge 46 between enclosure 44 and pressure vessel 34. Air supply line 14 is connected to air inlet port 66 to provide compressed air to enclosure 44. Air inlet port 66 extends through first side 54 of enclosure 44. Inlet air pressure gauge 80 extends through first side 54 of enclosure 44 and is configured to provide a reading of the inlet air pressure entering enclosure 44 through air inlet port 66. Blast line 38 is connected to blast outlet port 68, which extends from first side 54 of enclosure, and is configured to receive an applicator flow from enclosure 44. Accessory outlet port 82 extends from back 60 of enclosure 44 and is configured to receive an accessory hose. Water inlet port 84 extends from bottom 64 of enclosure 44, and water inlet line 24 connects to water inlet port 84.
Control ports 70a and 70b extend from first side 54 of enclosure 44. Control line 86a extends from control port 70a, and control line 86b extends from control port 70b. Control line 86a and control line 86b extend to applicator 40 (shown in
Pressure pot 48 of pressure vessel 34 is filled with a media and water through fill inlet 50. Air supply line 14 is connected to air inlet port 66 and provides compressed air to the pneumatic lines (shown in
Water pump 20 pulls water into enclosure 44 through water inlet line 24 and water inlet port 84. Water pump 20 drives the water downstream through water regulator 22 (best seen in
Pressure pot 48 is initially charged to the fixed pot pressure. The regulated water flows into pressure pot 48 through pot pressure gauge 46, and pot pressure gauge 46 provides a pot pressure reading to the user. The regulated water pressurizes pressure pot 48 to the fixed pot pressure, at a level configured to be above a maximum blast air pressure. The pot pressure reading indicates to the user that pressure pot 48 is pressurized for blasting. While the fixed water pressure is described as being fixed above a maximum blast air pressure, it is understood that water regulator 22 may be set such that any desired fixed water pressure is provided downstream of water regulator 22. As such, while water regulator 22 is generally set to provide the fixed water pressure prior to a user receiving vapor blast system 10, it is understood that water regulator 22 may be configured to be either fixed before user operation or adjustable by the user.
With media line 36 and manifold line 18 (best seen in
Water regulator 22 maintains the regulated water flow throughout the blast process. The regulated water flows to pressure pot 46 and maintains the pot pressure above the blast air pressure. Maintaining the pot pressure above the blast air pressure ensures a consistent flow of blast mixture to applicator 40. In addition, the regulated water flow returns the pot pressure to the fixed pot pressure when applicator 40 is deactivated such that vapor blast system 10 is idling. With applicator 40 deactivated, the regulated water flow maintains the pot pressure at the fixed pot pressure, preferably above a maximum blast air pressure, which ensures that the blast mixture will flow to manifold line 18 and downstream through blast line 38 regardless of the blast air pressure set by the user.
Air inlet port 66 extends through first side 54 of enclosure 44 and is connected to air supply line 14. Air supply line 14 extends to air regulator 88, through which compressed air flows. Manifold line 18 extends from air regulator 88 and to blast outlet port 68, and blast outlet port 68 extends through first side 54 of enclosure 44. Blast line 38 extends from blast outlet port 68 and to applicator 40 (shown in
Control line 86a extends from pump control line 92 and to control port 70a. Control line 86a extends outside of enclosure 44 from control port 70a and to applicator 40. Control line 86b extends from control valve 94 and to control port 70b. Similar to control line 86a, control line 86b also extends outside of enclosure 44 from control port 70b to applicator 40. Triggering applicator 40 connects control line 86a and control line 86b such that the system air portion may flow through control line 86a, to control line 86b, and to control valve 94 to actuate control valve 94 based on a trigger position.
Flow valve line 102 extends from control valve 94 and to flow valve 114. Air regulator line 96 extends from control valve 94 and to air regulator 88. Blast air control 76 is connected to air regulator line 96 and is configured to control the air flow to air regulator 88 through air regulator line 96, to thereby control the volume and pressure of the blast air portion allowed to flow downstream through air regulator 88. With both flow valve line 102 and air regulator line 96 attached to control valve 94, triggering applicator 40 causes control valve 94 shift between a first position and a second position to control an airflow through flow valve line 102 and air regulator line 96. For example, with applicator 40 not triggered, control valve 94 may direct air through flow valve line 102 to flow valve 114, thereby actuating flow valve 114 to the closed position. At the same time, control valve 94 prevents air from flowing through air regulator line 96, thereby maintaining air regulator 88 in a normally closed position. When applicator 40 is triggered, air is directed through air regulator line 96 and prevented from flowing through flow valve line 102, and as such, air regulator 88 is opened by the airflow through air regulator line 96 and flow valve 114 is opened because flow valve line 102 is depressurized.
Water inlet port 84 extends through bottom 64 of enclosure 44. Water inlet port 84 receives water inlet line 24 at pump inlet 108, and pumped water line 26 extends from pump outlet 110 and downstream to selector valve 28. Water regulator 22 is disposed on pumped water line 26 between water pump 20 and selector valve 28. While water regulator 22 is described as disposed between water pump 20 and selector valve 28, it is understood that water regulator may be placed at any desired location downstream of water pump 20 and upstream of pressure vessel 34, such as on pumped water line 26 or pressurizing lines 30.
Accessory line 32 extends from selector valve 28 and to accessory outlet port 82. Pressurizing lines 30 extends from selector valve 28 and to needle valves 104, and pressurizing lines 30 extends from needle valves 104 and to pot supply outlet ports 106. Wash line 112 extends from selector valve 28 to media inlet port 72. While two pressurizing lines 30 are shown, it is understood that vapor blast system 10 may include as few or as many pressurizing lines 30 for conveying regulated water to pressure vessel 34 (best seen in
Media inlet port 72 extends through bottom 64 of enclosure 44. Manifold line 18 extends from air regulator 88 and to blast outlet port 68, and blast outlet port 68 extends through first side 54 of enclosure 44, similar to air inlet port 66. Blast line 38 extends from blast outlet port 68 and to applicator 40. Media line 36 extends from pressure vessel 34, through media inlet port 72, and to manifold line 18 to provide a blast mixture to manifold line 18 to generate an applicator flow comprised of compressed air, media, and water. More specifically, conveying hose 116 extends from pressure pot 48 and to media inlet port 72, and flow hose 118 extends from media inlet port 72 and to manifold line 18. Flow valve 114 is configured to the blast mixture flow through flow hose 118, such that the blast mixture flow is prevented from entering manifold line 18 when flow valve 114 is in a first position and the blast mixture flow flows to manifold line 18 when flow valve 114 is in a second position. For example, flow valve 114 may be a pinch valve and flow hose 118 may be a pinch hose, such that in the first position flow valve 114 compressed flow hose 118 to close any flow opening through flow hose 118, and in the second position flow valve 114 disengages from flow hose 118 to allow the blast mixture flow through flow hose 118.
Pressure vessel 34 is loaded with a supply of media and water by a user, thereby generating the blast mixture. The user disengages disconnect 74, thereby permitting the system air portion to flow through system line 16 between air supply line 14 and control valve 94. Compressor 12 (shown in
The system air portion flows to control valve 94 and to control line 86a. The system air portion is also provided through pump control line 92 to power water pump 20, such that pumped water is provided downstream of water pump 20 whenever compressor 12 is activated, regardless of if applicator 40 is triggered. The system portion also flows through control line 86a and to applicator 40. Before applicator 40 is triggered, a part of the system air portion flows into control valve 94 through system line 16. The part of the system air portion provided to control valve 94 through system line 16 is directed to either flow valve line 102 to shift flow valve 114 to the first position where metering hose 118 is closed, or air regulator line 96 to shift air regulator 88 to an open position to allow the blast air portion to flow to manifold line 18. With control line 86a disconnected from control line 86b, the part of the system air portion is directed to flow valve line 102, such that both flow valve 114 and air regulator 88 are closed.
With flow valve 114 and air regulator 88 closed, water pump 20 continues to drive water downstream through pumped water line 26 and to water regulator 22 to generate the regulated water. The regulated water is provided to pressure vessel 34 through pressurizing lines 30 to pressurize pressure vessel 34 to the fixed pot pressure, which is controlled by the fixed water pressure of the regulated water. The regulated water maintains the pot pressure at the fixed pot pressure whenever compressor 12 is activated and flow valve 114 is closed.
When applicator 40 is triggered, control line 86a is connected to control line 86b such that compressed air is provided to control valve 94 through control line 86b. The compressed air flowing through control line 86b actuates control valve 94 such that compressed air may flow through air regulator line 96 and actuate air regulator 88 to an open position such that compressed air may flow to blast line 38 through air regulator 88. At the same time, control valve 94 shifting prevents compressed air from flowing to flow valve 114 through flow valve line 102. As such, the pressure maintaining flow valve 114 in the first position is relieved, and the blast mixture is allowed to flow through flow hose 118.
Blast pressure gauge 78 is connected to air regulator 88 by blast gauge line 98, and blast pressure gauge 78 provides the user with a blast air pressure reading. Blast air control 76 allows a user to adjust the air provided through air regulator line 96, such that the blast air portion allowed through air regulator 88 is set by the user. With air regulator 88 opened, the blast air portion is able to flow downstream through air regulator 88 and to manifold line 18.
With both flow valve 114 and air regulator 88 open, the blast mixture is combined with the blast air portion in manifold line 18. The combined blast mixture and blast air portion are provided to blast line 38 and downstream to applicator 40 to be applied to a substrate. With flow valve 114 open, the blast mixture flows out of pressure vessel 34 and water pump 20 drives water into pressure vessel 34 to replace the blast mixture flowing out of pressure vessel 34. The blast mixture flowing to manifold line 18 causes the pot pressure to drop below the fixed pot pressure. Water regulator 22 is configured to output regulated water having the fixed water pressure, and the regulated water flows downstream from water regulator 22, through pumped water line 26, to selector valve 28, and through pressurizing lines 30 and needle valves 104 and to pressure vessel 34. The regulated water maintains the pot pressure at a level proximate, but still above, the blast air pressure. As such, the user will notice that the pot pressure has dropped, but that the pot pressure is maintained at a steady level relative to the blast air pressure, such that a differential between the pot pressure and the blast air pressure drives the blast mixture through media line 36 and to manifold line 18.
Water regulator 22 regulates the regulated water pressure to maintain the pot pressure at a level greater than the blast air pressure throughout the vapor blast process. For example, water regulator 22 may include internal components, such as a diaphragm and poppet valve, configured to shift along with the upstream to downstream pressure differential about water regulator 22, to allow the regulated water to flow through water regulator 22 to control the pot pressure. By controlling the pot pressure such that the pot pressure is always greater than the blast air pressure, water regulator 22 eliminates any need for the user to set the pot pressure and ensures that the pot pressure is always safely above the blast air pressure. As such, water regulator 22 ensures that the blast mixture will always flow into manifold line 18 to combine with the blast air portion.
Disengaging the trigger on applicator 40 disconnects control line 86a from control line 86b, thereby disconnecting the airflow to control valve 94. With the airflow to selector valve 28 through control line 86b shut off, air is prevented from flowing through air regulator line 96 and is directed through flow valve line 102. Flow valve 114 thus closes, preventing the blast mixture flow through flow hose 118. Closing flow hose 118 causes the pot pressure to rise within pressure vessel 34 and thus in pressurizing lines 30 and pumped water line 26. The pot pressure continues to rise until the pot pressure reaches the fixed pot pressure, which then causes water regulator 22 to cut off any additional water flow through water regulator 22, thereby ensuring that the fixed pot pressure is maintained at the fixed water pressure. When flow valve 114 shifts to the open position, the blast mixture exits pressure vessel 34 leading to a drop in the pot pressure, and the drop in the pot pressure causes water regulator 22 to allow additional water to flow to pressure vessel 34 to maintain the pot pressure above the blast air pressure. While water regulator 22 maintains the fixed pot pressure above the maximum blast air pressure, it is understood that the pot pressure may drop below the maximum blast air pressure during operation, but water regulator 22 ensures that the pot pressure is always above the blast air pressure actually utilized during blasting.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.
This application is a National Stage Application based on PCT/US2016/042585 filed Jul. 15, 2016, which claims priority to U.S. Provisional Application No. 62/193,235 filed on Jul. 16, 2015, and entitled “Vapor Blast System with Fixed Pot Pressure Setting.”
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2016/042585 | 7/15/2016 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62193235 | Jul 2015 | US |
