DE102011119826A1 - Method for producing a blasting abrasive, method for blasting, blasting abrasive, apparatus for producing a blasting abrasive, apparatus for blasting - Google Patents

Abstract

The invention relates to a method for producing an abrasive blasting agent (18) from CO2 dry ice (16) and water ice (15) by producing the CO2 dry ice (16) and the water ice (15) separately and optionally producing the water ice (15). is further cooled in one or more steps and then mixed with the CO2 dry ice (16), the temperature of the mixture being achieved by the coldness of the CO2 dry ice (16) and additional cooling with the help of a special refrigerant mixture in a cold chamber (17) (18) of down to -70 ° C is reached and thus the water ice (15) reaches the hardness of glass.

Description

The invention relates to a method for producing a blasting abrasive according to the preamble of claim 1, a method for blasting according to the preamble of claim 9, a blasting abrasive according to the preamble of claim 11, an apparatus for producing a blasting abrasive according to the preamble of claim 12 and a Device for blasting according to the preamble of claim 14.

Various methods of blasting bodies, surfaces, interiors and the like are known. These methods are used with different abrasives especially for cleaning contaminated surfaces. In addition to high-pressure water, glass beads, slag, sands or salts are used as blasting agents in a blasting medium, such as water or compressed air. A disadvantage of these cleaning technologies that deposit the residues in the environment and in the system to be cleaned. This has the consequence that the components to be cleaned must be removed and cleaned in appropriate workshops.

Greater importance has therefore been gained recently cold blasting. CO ₂ pellets, CO ₂ snow or generally CO ₂ particles and compressed air are used as energy source. A disadvantage of cleaning with CO ₂ as a blasting agent, however, is that no or only a slight abrasive effect is recorded. However, this low abrasiveness limits the range of application for this cleaning technology.

Out WO 2003 101667 A1 is known CO ₂ pellets used as a solid abrasive for cleaning surfaces. The CO ₂ pellets act as a soft, not very abrasive blasting agent, causing no damage to the surface to be cleaned. Due to the temperature of about -78 ° C, the CO ₂ pellets caused a thermoelectric voltage between contamination and to clean component, which leads to the separation of the impurity (cryogenic effect).

In the DE 102 59 132 B4 describes a method in which CO _{2 is used} as the core jet and nitrogen as the sheath jet. Disadvantages are the high pressures and the high consumption of gas.

In the JP 601 45 905 A a method is described in which the dry ice (CO ₂ particles) by adding water to the resulting liquid CO ₂ while relaxing CO ₂ snow is to have a higher hardness.

The DE 35 05 675 A1 describes a method for removing surfaces, in which water ice (water particles) is added to a water jet. The water jet is pressed with a dependent on the component to be cleaned, pressure on the surface to be cleaned. The water ice can also be formed by ice-forming germs within the water jet. A disadvantage of this method is that no cryogenic effect occurs but only a mechanical removal is recorded.

The DE 10 2006 002 653 B4 describes a process in which a certain amount of water is added to a dry ice stream.

In DE 100 10 012 A1 describes a device in which CO ₂ pellets or CO ₂ particles are mixed to improve the cleaning performance with a blasting agent solid at room temperature. A disadvantage is the low constancy of the quantitative ratio between CO ₂ radiation agent and the additional abrasive.

In the US 5,785,581 describes a system in which a cryogenic liquid, preferably liquid nitrogen, is used as a coolant for the production of ice particles. Here, water droplets are introduced into a cooled compressed air stream, converted into ice and transported using the pressure gradient from the jet nozzle. Again, only a mechanical effect is recorded.

In the DE 10 2010 020 618 A1 For example, a process for producing CO ₂ pellets or CO ₂ particles having increased mechanical hardness and abrasiveness is described, wherein CO ₂ water ice particles are produced by supplying water. The disadvantage of this is that the CO ₂ irrigation ice particles still need to be crushed and thereby can be caused by the required pressure, again small amounts of water.

After the cited prior art has not shown a satisfactory solution, in particular for producing a suitable low-residue and abrasive blasting agent, the object of the present invention is to provide a production method for a blasting agent that has a controllable abrasiveness and thus impurities from surfaces as possible can be removed without residue. In particular, the component itself should not be damaged or removed.

This object is achieved by a blasting method according to claim 1, a blasting method according to claim 9, a blasting abrasive according to claim 11, an abrasive blasting apparatus according to claim 12 and a blasting apparatus according to claim 14. specified dependent claims.

The inventors have recognized that the object can be achieved in a surprising manner in that first solid particles of CO ₂ and second solid particles are produced separately from water and then combined, in particular mixed. The fact that only the generation and then the mixing of the particles takes place, on the one hand, a different shape and size processing of the particles can be done. In addition, it is possible to work at different temperatures and thus optimally adjust the generation of the abrasive mixture.

In a preferred development, the first and second particles are produced by crushing. As a result, larger units, such as blocks of dry ice and water ice can be used, which is advantageous in terms of energy and storage.

Alternatively or additionally, it can be provided that the separately produced first and / or the second particles are comminuted before being combined. As a result, the size can optionally be adjusted to the desired size in the blasting agent mixture after a certain temperature setting of the particles. Suitably, the temperature of the first particles is -60 ° C to -80 ° C, preferably -70 ° C. And appropriately, the temperature of the second particles is -10 ° C to -40 ° C, preferably -15 ° C to -30 ° C, especially -25 ° C.

From the literature ( B. Karpuschewski et al., Basic Deburring Considerations as a Novel Method for Deburring Complex Components (1) and A. Momber, Manual for Surface Treatment of Concrete (2)), in particular from (1) it is known that the hardness of the water ice is temperature-dependent. The hardness of the water ice is inversely proportional to its temperature. This means that with decreasing temperature the hardness of the water ice rises. Thus, water ice with a temperature of -10 ° C has a Mohs hardness of 2, comparable to gypsum. By comparison, water ice at -80 ° C has a Mohs hardness of 6-7, which is comparable to the hardness of glass or steel.

In the product information: NOCK, Fleischereimaschinen GmbH Scherbeneiserzeuger and the product information ZIEGRA Eismaschinen GmbH plants for the production of water ice in different sizes and structures are described. These can be used in the context of the present invention as commercially available water ice makers.

If the water ice pieces have a temperature of -1 ° C to -10 ° C, the surface is then still relatively humid. The water ice pieces have in this state only a small hardness and size, which is higher than that of the CO ₂ particles. If these pieces of water ice are mechanically comminuted to the desired size, water is re-formed, since the comminution tools have room temperature. If the water ice pieces, however, brought to a temperature of about -60 ° C to -70 ° C, they have, as determined in experiments, although a high hardness, but require for crushing a very high pressure, which in turn a local Water formation favors.

With these too low or too high temperatures of the water ice, therefore, during the subsequent contact with the CO ₂ particles, a block formation occurs in the CO ₂ water ice mixture, ie the CO ₂ and water particles stick together.

It is advantageous if in the blasting medium mixture the first particles have a dimensioning of 0.4 mm to 1 mm, preferably 0.6 to 0.8 mm in the cross-section means and / or the second particles have a dimension of 0.6 mm to 1.2 mm, preferably 0.8 to 1.0 mm in the cross-sectional means. These sizes have proven to be effective during blasting.

Particularly advantageously, the second particles are produced as flake ice prior to merging.

The term "cross-sectional means" in this context means that the dimension with the least strength has this size on average. In the case of flake ice, which has a spatial curvature due to the cylindrical geometry of the flake ice maker, it is therefore the mean thickness of the flake ice.

This dimensioning or the use of flake ice on the one hand causes a better size control. On the other hand, the manufacturability is facilitated because you do not have to work at high pressures to break the flake ice. Furthermore, the low pressure prevents the formation of water. In a preferred embodiment, the size and / or size distributions of the first and the second particles are each adjusted so that in each case the same masses or mass distributions result for the first and second particles. This is therefore of particular importance, because otherwise it can lead to a change in the set mixture or even to a segregation. Due to the fact that the density of dry ice is approx. 1.56 g / cm ³ , whereas that of water ice is approx. 1.00 g / cm ³ , the particle sizes of CO ₂ must be adjusted to equal masses or mass distributions. Particles to water ice particles behave inversely proportional to allow it to move through the compressed air flow does not change the set mixing ratio. As a rule, values can not be kept exactly constant, which is why distributions result. When adjusting the masses or mass distributions via the targeted dimensioning, it must be ensured that these must be different depending on the temperature at hand.

The abrasiveness of the blasting agent is preferably adjusted by specifically setting the mixing ratio between the first and second particles, the shape of the second particles, the size of the second particles and / or the temperature of the second particles in the blasting medium. With regard to the shape of the second particles, edged water ice particles have a higher abrasiveness than those with curves. Larger second particles have a higher abrasiveness than smaller ones. A mixture with more second particles has a higher abrasiveness than with less second particles. The mixture can be arbitrarily set, for example, via the rotational speeds of respective shredders for the first and second particles. And the second particles have a higher abrasiveness at lower temperatures.

Suitably, the size of the first and / or second particles in their production is so much greater than the size set in the blasting agent adjusted to compensate for size losses caused in the production of the blasting agent. As a result, the desired size of the particles in the blasting medium is reliably achieved, despite the particles generated in the merger lose in size. For example, the first particles of CO _{2 become} smaller because they cool the second particles by sublimation. Although it is preferred that the second particles are further cooled after their preparation in a special transport cooling unit, wherein they reach temperatures of about -20 ° C. At this temperature they have a hardness that is favorable for comminution and are dry. However, the hardness achieved does not yet bring the desired abrasiveness. A further increase in the abrasiveness of the CO ₂ water ice mixture is achieved by mixing the CO ₂ particles and water ice particles, which have been comminuted separately in a certain ratio, after comminution in a further cold chamber. When mixing in the cold chamber, there is a direct contact between the CO ₂ particles with a temperature of about -78 ° C and the water ice particles which have a temperature of about -20 to -30 ° C. This direct contact leads to an energy exchange between the CO ₂ particles and the water ice particles. The water ice particles release heat, thereby increasing their hardness and the CO ₂ particles absorb the heat released, which leads to a softening of the surface or to a formation of CO ₂ gas.

Particularly advantageously, the CO ₂ gas produced after the merging is used as a protective gas against heating and ambient air and / or used for cooling the second particles.

Alternatively or additionally, the cooling can be further improved by using CO ₂ snow, liquid nitrogen and / or frozen compressed air to cool the second particles.

In a further preferred embodiment, it is provided that the first and second particles are stored so separated from each other before the merger that an at least partial temperature exchange can take place.

Advantageously, the first particles, the second particles and / or the blasting agent are cooled in two or more cooling planes. This significantly increases the cooling capacity.

Independent protection is claimed for a method of blasting bodies, surfaces, interiors and the like using the blasting agent produced according to the invention. With the blasting agent according to the invention, which can be produced at arbitrarily low temperatures, it is possible to achieve a uniformly clean, smooth surface which is free from damage by the blasting agent and free of condensate and flash rust. This CO ₂ water ice mixture remains constant in its composition and abrasiveness, ie very stable as long as the parameters particle size and temperature remain constant. For this purpose, therefore, the rotational speeds, for example, of comminution rollers and the temperature in the cold chamber should be monitored.

In a particularly expedient development, a dried compressed air stream is used as dosing flow for the metering of the blasting medium and / or the blasting agent is provided with a dried compressed air stream as a jet stream having a temperature of + 40 ° C. to + 90 ° C., preferably + 50 ° C to + 90 ° C, in particular + 70 ° C to + 80 ° C. If the object to be irradiated itself is already heated, as is the case, for example, with vulcanizing molds, a separate heating of the jet stream can be dispensed with.

If the component to be cleaned is not heated, the heat capacity decreases as a result of the removal of heat during the transition of the CO ₂ particles from the solid to the gaseous state. This leads to a deterioration of the cleaning performance and the formation of condensate. To avoid the deterioration of the cleaning performance of the compressed air is dried here and heated depending on the contamination. This dry and hot compressed air stream is converted into CO ₂ Water ice mixture added. The CO ₂ irrigation mixture is not damaged by the hot compressed air flow, since it is exposed to the above-mentioned temperature only a short time at the high flow rate and the short distance from blasting machine to the blasting machine and due to the Leydenfrost phenomenon an insulating gas envelope around the individual particles of CO ₂ forms water ice mix. The hot and dry compressed air stream absorbs the moisture from the environment after leaving the jet nozzle and thus prevents condensation on the surface of the component to be cleaned.

The fact that a dried compressed air flow is used as metering, which was not additionally heated, the method is also suitable for longer life.

Furthermore, independent protection is claimed for the blasting agent produced according to the invention, which has solidified CO ₂ and solidified water. This blasting agent may also be separately prepared and delivered to blasting devices with suitable intermediate storage which maintains the desired temperature and humidity of the blasting medium.

In addition, independent protection is claimed for a device for producing a blasting medium for blasting bodies, surfaces, interiors and the like, which has solidified CO ₂ and solidified water and is characterized in that supply means for separately generated first solid particles of CO ₂ and second solid particles of water are provided and in particular a mixer for the first and second particles is provided. The supply means can be designed, for example, as independent transport means, for example conveyor belts or transport plates. However, a common means of transport can be provided, which is fed from two separate containers for the separately produced first and the second particles.

• – Zerkleinerer zur Herstellung der ersten und zweiten Partikel und/oder Zerkleinerer zum Zerkleinern der ersten und/oder zweiten Partikel;
• – Mittel, das Zerkleinern der ersten Partikel bei Temperaturen von –60°C bis –80°C, bevorzugt –70°C vorzunehmen und/oder Mittel, das Zerkleinern der zweiten Partikel bei Temperaturen von –10°C bis –40°C, bevorzugt von –15°C bis –30°C, insbesondere –25°C vorzunehmen;
• – Mittel, den ersten Partikeln eine Dimensionierung von 0,4 mm bis 1 mm, bevorzugt 0,6 bis 0,8 mm im Querschnittsmittel zu geben und/oder Mittel, den zweiten Partikeln eine Dimensionierung von 0,6 mm bis 1,2 mm, bevorzugt 0,8 bis 1,0 mm im Querschnittsmittel zu geben, wobei die Vorrichtung insbesondere einen Scherbeneiserzeuger aufweist;
• – Mittel, die Größe und/oder Größenverteilungen der ersten und der zweiten Partikel jeweils so einzustellen, dass sich für die ersten und zweiten Partikel jeweils dieselben Massen oder Massenverteilungen ergeben;
• – Mittel, das Mischungsverhältnis zwischen ersten und zweiten Partikeln, die Form der zweiten Partikel, die Größe der zweiten Partikel und/oder die Temperatur der zweiten Partikel im Strahlmittel gezielt einzustellen;
• – Mittel, die Größe der ersten und/oder der zweiten Partikel bei deren Erzeugung soviel größer als die die im Strahlmittel gewünschte Größe einzustellen, um bei der Herstellung des Strahlmittels bewirkte Größenverluste auszugleichen;
• – Mittel, das nach dem Zusammenführen entstehende CO₂-Gas als Schutzgas gegen Erwärmung und Umgebungsluft einzusetzen und/oder zur Kühlung der zweiten Partikel einzusetzen;
• – Kühlungsmittel zur Kühlung der zweiten Partikel, die CO₂-Schnee, flüssiger Stickstoff und/oder tiefgekühlte Druckluft verwenden;
• – Mittel, die ersten und zweiten Partikel vor der Zusammenführung so getrennt voneinander zu lagern, dass ein zumindest teilweiser Temperaturaustausch stattfinden kann und/oder
• – zwei oder mehreren Kühlebenen zur Kühlung der ersten Partikel, der zweiten Partikel und/oder des Strahlmittels.

Further particularly advantageous features of this device, which can be combined with one another as desired, are:

• - Crusher for producing the first and second particles and / or crushers for crushing the first and / or second particles;
• Means for comminuting the first particles at temperatures of -60 ° C to -80 ° C, preferably -70 ° C, and / or means for comminuting the second particles at temperatures of -10 ° C to -40 ° C, preferably from -15 ° C to -30 ° C, in particular -25 ° C make;
• - means to give the first particles a dimensioning of 0.4 mm to 1 mm, preferably 0.6 to 0.8 mm in the cross-sectional means and / or means, the second particles have a dimension of 0.6 mm to 1.2 mm to give preferably 0.8 to 1.0 mm in the cross-sectional means, wherein the device in particular has a flake ice maker;
• - Means, the size and / or size distributions of the first and the second particles in each case to be adjusted so that in each case the same masses or mass distributions result for the first and second particles;
• - Means to set the mixing ratio between the first and second particles, the shape of the second particles, the size of the second particles and / or the temperature of the second particles in the blasting agent targeted;
• - Means, the size of the first and / or the second particles in their production so much greater than the set in the blasting medium size to compensate for the production of the blasting agent caused size losses;
• - means to use the resulting after merging CO ₂ gas as a protective gas against heating and ambient air and / or to use for cooling the second particles;
• Cooling means for cooling the second particles using CO ₂ snow, liquid nitrogen and / or cryogenic compressed air;
• Means for storing the first and second particles separately from each other prior to the merger so that at least partial temperature exchange can take place and / or
• - Two or more cooling planes for cooling the first particles, the second particles and / or the blasting agent.

Finally, independent protection is claimed for a device for blasting bodies, surfaces, interiors and the like, comprising means for providing a stream of compressed air and means for providing a blasting agent, which is characterized in that the means for providing the blasting agent as the inventive device for Making a blasting agent is formed.

Advantageously, this device for blasting dosing for metering the blasting agent, which use a dried compressed air stream as Dosierstrom and / or this device for blasting advantageously irradiation means for applying the irradiating object with the blasting agent, which use a dried compressed air stream as a jet stream, the a temperature of + 40 ° C to + 90 ° C, preferably + 50 ° C to + 90 ° C, in particular + 70 ° C to + 80 ° C.

It has become clear that the present invention provides a novel production process, in particular novel CO ₂ pellets or CO ₂ particles prior to entering into the Compressed air flow with as edged water ice particles that are cooled in one or more stages, so they have a high hardness, brings together that a stable abrasive CO ₂ water ice mixture is formed, with the particular adjustment of the abrasivity in addition the temperature of the blasting medium is adjustable, with temperature of about -70 ° C are preferred. The temperature adjustment takes place in particular in a separate cold chamber, in which the CO ₂ irrigation water mixture is cooled in several stages gradually to -60 ° C to -70 ° C, so that the water ice particles, for example, reach the desired hardness of glass.

The comminution of the CO ₂ particles and the water ice particles is preferably carried out separately in one or more steps in a compact comminution block which is indirectly cooled by the CO ₂ particles, thereby preventing the re-formation of water in the comminuting tools.

The fact that the masses are set the same, the CO ₂ - and water ice particles are collected after crushing on an inclined baffle and mixed according to the speed ratio of the two crushing units. Laterally mounted vibrators set the cold chamber in vibration and cause the individual particles of CO ₂ water ice mixture on the individual baffles, while maintaining the mixing ratio, are led to the dosing unit.

Although compressed air is preferably used, other gases can nevertheless also be used, so that in the claims in each case generalization is referred to as "fluid flow".

The features and advantages of the present invention will become apparent in the following with reference to the description of various preferred embodiments in conjunction with the figures. Showing:

1 the device according to the invention for producing the blasting agent according to the invention and blasting in a first preferred embodiment,

2 the device according to the invention for producing the blasting medium according to the invention and blasting in a second preferred embodiment,

3a . 3b the inventive device for producing the blasting agent according to the invention in a third preferred embodiment and

4 the inventive device for producing the blasting agent according to the invention and for blasting in a third preferred embodiment.

In 1 and 2 are purely schematically two different preferred embodiments of the device A, B according to the invention of the production of the blasting agent according to the invention and shown in section for blasting, wherein the same elements are provided with the same reference numerals.

In 1 It can be seen that with conventional water ice conditioners 1 prepared water ice, preferably flake ice 2 , with a temperature of about -7 ° C, with the help of a small conveyor belt 30 either on the conveyor belts 3 in the transport unit 5 or in the water tank 31 is encouraged. That to produce the flake ice 2 Required water comes with a pump 32 from the water tank 31 into the water ice dresser 1 promoted.

On the conveyor belts 3 in the closed and externally insulated transport unit 5 over cooling blocks 4 run and from the drive shafts 33 being moved becomes the flake ice 2 from the water ice dresser 1 to the crusher plant 6 transported and further cooled to about -25 ° C. The cooling takes place through the cooling blocks 4 and gets through, outside the transport unit 5 attached fan 7 achieved that in the housing 5 located air over the upper nozzle 8th sucks and over the lower neck 9 back into the transport unit 5 blows.

The ones on the cooling blocks 4 resting baffles 10 are mutually offset on one side and force the air flow to flow through the spaces in the cooling blocks 4 the with a special coolant mixture of the refrigeration unit 37 flowed through and cooled. The air flow flows perpendicular to the direction of movement of the conveyor belts 3 , This ensures that the air flows through the cooling blocks 4 cooled and when overflowing through the conveyor belts 3 moving flake ice 2 this deprives a certain amount of heat.

After the flake ice 2 on the conveyor belts 3 the transport unit 5 It passes through several stages and has reached the desired temperature of about -20 to -30 ° C, it reaches a small funnel 11 and from there to the crusher plant 6 , Next to the crusher plant 6 is the CO ₂ grinder 12 , Above the CO ₂ grinder is the reservoir 13 for the CO ₂ pellets 14 arranged. The small funnel 11 , the crusher plant 6 , the reservoir 13 and the CO ₂ mill 12 form a closed unit. This will be reached that crusher plant 6 and the small funnel 11 through the CO ₂ pellets 14 in the storage container 13 get a certain pre-cooling and warm up only slightly during short breaks.

The crusher plant 6 is constructed in the usual way with hammer wheels and an anvil bar. The CO ₂ grinder shown is formed with opposing rollers.

While the flake ice 2 , due to the nature of the production, already in the water ice conditioner 1 Partially crushed by scraping and by changing the conveyor belts 3 continue, but undefined, crushed, become the flake ice 2 in the crusher plant 6 and the CO ₂ pellets 14 in the CO ₂ grinding plant 12 shredded to a well-defined size. The size ratio of the water ice particles formed during comminution 15 to the CO ₂ particles 16 is in inverse proportion to the density of the particles produced 15 . 16 , The resulting CO ₂ - 16 and water ice particles 15 are then in a cold chamber 17 , in their basic structure that of the transport unit 5 is similar and just below the shredding units 6 . 12 is, mixed. The mixing ratio between CO ₂ - 16 and water ice particles 15 is variable and by the speed of the CO ₂ -Mahlwerkes 12 for the CO2 pellets 14 adjustable.

The cooling of the cold chamber 17 takes place through a special cooling block 36 that of a refrigerant mixture from the refrigeration unit 37 is flowed through. In the cold chamber 17 becomes the CO ₂ water ice mixture 18 gradually cooled to about -70 ° C by placing on trays 20 in multiple levels 35 , under a certain angle of attack 21 are arranged to each other, mixed and by the vibration of the cold chamber 17 passing through a jogger 19 is generated by a plane 35 is transported to the other.

During mixing, the CO ₂ particles come 16 with a temperature of about -70 ° C with the water ice particles 15 , which have a temperature of about -20 to -30 ° C, in direct contact. Through the contact, moving through the vibration and the transition from one level 35 constantly changing, there is an energy exchange between the CO ₂ particles 16 and the water ice particles 15 , The CO ₂ particles 16 remove the water ice particles 15 Energy and sublimate. Energy deprivation turns the water ice particles 15 colder and harder. The CO ₂ particles 16 become porous and soft by the transition of a part of their substance in the gaseous state at the surface.

The gradual decrease in temperature in the cold chamber 17 assists reconsolidation of CO ₂ particles 16 and the further increase in the hardness of the water ice particles 15 , The resulting from the sublimation CO ₂ gas, which is known to be heavier than air, remains in the cold chamber 17 and prevents the ingress of ambient air or can help to support cooling in the cold chamber 17 be used.

The CO ₂ -water-ice-cream 18 with a temperature of about -70 ° C is the compressed air flow 22 in a dosing unit 23 added. The main compressed air flow 22 is absolutely dry (water content less than 0.05 g / m ³ ) and has a temperature of about + 25 ° C. The main compressed air flow 22 is divided, with one part as Dosierstrom 24 to the dosing unit 23 that are under the cold chamber 17 located, and there with the CO ₂ irrigation mixture 18 is loaded. The other part 25 of the main compressed air flow 22 is called beam current 25 in the air heating 26 heated to a temperature of + 50 ° C to + 80 ° C and then in the mixing chamber 27 with the dosing flow 24 reunited and the blasting gun 28 guided.

• – eine Vorwärmung des verunreinigten Bereiches
• – eine gegenüber dem normalen CO₂-Verfahren abrasivere Reinigung
• – eine Erwärmung des durch die Reinigung gekühlten Bereiches
• – die Verhinderung einer Bildung von Kondensat.

By separating the main compressed air flow 22 is a heating of the dosing unit 23 , especially avoided during jet breaks. Partial heating of the main compressed air flow 22 causes the cleaning jet 29 the following effects on the component to be cleaned:

• - a preheating of the contaminated area
• - A more abrasive compared to the normal CO ₂ process
• - Heating of the cooled by the cleaning area
• - Preventing the formation of condensate.

In 2 It can be seen that the solid CO ₂ in blocks 38 delivered and in insulated containers 39 is stored. The same goes for the water ice 40 , The blocks of CO ₂ 38 and water ice 40 are used to make the CO ₂ water ice mixture 41 in cooled and insulated shafts 49 for the CO ₂ blocks 42 and for the water ice blocks 43 pushed and lie on the rasp 44 for CO ₂ , and the rasp 45 for water ice.

The rasps 44 . 45 have different divisions, which are adapted to the density ratio. The CO ₂ particles 47 be using the CO ₂ rasp 44 from the CO ₂ block 38 and the water ice particles 48 be using the water ice grater 45 from the water ice block 40 separated. The resulting water ice particles 48 are cooled further, according to Example 1 to about -25 ° C and in the cold chamber 17 with the CO ₂ particles 47 mixed. For mixing, the CO ₂ particles 47 with the help of the rotary valve 50 from the CO ₂ storage tank 46 and the water ice particles 48 with the help of the rotary valve 51 in the cold chamber 17 brought. The mixing ratio is determined by the different Speeds of the CO ₂ rasp 44 and the water ice grater 45 set.

After mixing the CO ₂ particles 47 with the water ice particles 48 in the cold chamber 17 The same energetic processes take place as they are referring to 1 have been described. The cooling process leading to the formation of the hard CO ₂ -water ice mixture 41 is required, can be additionally supported by the injection of small amounts of CO ₂ snow or liquid nitrogen or deep-frozen compressed air. By blowing in, the overall energy exchange is improved and accelerated by the generated flow.

In the 3a . 3b purely schematically shows a third preferred embodiment of the inventive device C for producing the blasting agent according to the invention, wherein the same elements as in 1 and 2 have the same reference numerals.

It can be seen that in turn commercial CO ₂ pellets 14 and with the help of a commercially available water ice conditioner 1 Water ice, preferably flake ice 2 , be provided separately. The water ice 2 is in a transport unit 5 cooled down to about -25 ° C (the corresponding elements are only partially shown). Then the flake ice becomes 2 in the crusher plant 6 and the CO ₂ pellets 14 in the CO ₂ grinding plant 12 brought to the desired size.

The mixing takes place here now in a double-walled cylindrical cooling unit 52 in which the individual CO ₂ particles 16 and the water ice particles 15 after crushing in a collecting funnel 53 to merge. The cylindrical cooling unit 52 has several annular Kühlebenen 54 under which are cooling coils 55 (see in particular 3b ). The cooling coils 55 are with the cooling tubes 59 that in the double wall 61 the cylindrical cooling unit 52 run, connected. The cooling coils 55 and the cooling pipes 59 are traversed by a refrigerant mixture, which passes through the refrigeration unit 56 is moved.

The CO ₂ water ice mixture 18 falls on the upper annular Kühlebene 57 , The annular Kühlebenen 54 . 57 are not circumferentially closed, but each have a gap after 360 ° 58 through which the CO ₂ water ice mixture 18 to the next, deeper lying Kühlebene 54 falls. The interruptions 58 in the Kühlebenen 54 are staggered so that the cooling path is as long as possible. An agitator 60 with special sliders 62 cares for the mixing in the Kühlebenen 54 and move the CO ₂ water ice mixture 18 on the Kühlebenen 54 from the place of application to the gap 58 in the corresponding Kühlebene 54 , After the CO ₂ water ice mixture 18 all the Kühlebenen 54 . 57 it goes through in the dosing unit 23 the dosing flow 24 admixed.

In 4 is purely schematically illustrated a fourth preferred embodiment of the device D according to the invention for producing the blasting agent according to the invention, wherein the same elements as in 1 . 2 . 3a and 3b have the same reference numerals.

The apparatus D for cleaning components with the, proposed in the invention described above, CO ₂ water ice mixture 18 consists of several individual modules which, procedurally and functionally related to each other and in a common frame 61 are mounted.

The water ice dresser 1 , for the production of the flake ice 2 , is from the pump 32 supplied with water. The spatially curved flake ice 2 falls on the small conveyor 30 that by the engine 62 with the drive shaft 33 moved and through the pulley 63 with the clamping device 64 is guided and stretched. The small conveyor belt 30 carries the flake ice 2 to the transport unit 5 and pass it to the top band 30 the multiple superposed conveyor belts 30 , The conveyor belts 30 are in the closed transport unit 5 and transport the flake ice 2 in several stages to Brecherwerk 6 ,

For safe transport of the flake ice 2 are the sloping conveyor belts 30 with across the conveyor belts 30 running ribs 65 Mistake. The conveyor belts 30 run in each plane via drive shafts 33 and pulleys 63 , The drive shafts 33 are in the base plate 67 and in the mounting plate 68 stored and used by a motor 69 via a toothed belt 70 driven. Between the drive shaft 33 and the pulley 63 there is ever a cooling block 4 that of the support bars 71 is held.

In the lower part of the transport unit 5 There are several fans 72 the CO ₂ -containing air within the transport unit 5 move. The flake ice 2 is shuffled or reversed every time you transition from one level to another. The blowers 72 Moving CO ₂ -containing air is flowing through the cooling blocks 4 cooled and takes on the sweeping of the flake ice 2 Heat up. The alternating flow through 25 the cooling blocks 4 and repainting the flake ice 2 on the conveyor belts 30 is due to the mutual arrangement of the baffles 10 supported.

The transport unit 5 lies on the crusher plant 6 on. In the crusher plant 6 is the fixed anvil bar 73 and the hammer wave 74 with the hammer wheels 75 necessary for the desired crushing of the flake ice 2 to care.

Next to the crusher plant 6 is the CO ₂ -Mahtwerk 12 for crushing the commercial CO ₂ pellets 14 , Above the CO ₂ mill 12 is the reservoir 13 for the CO ₂ pellets 14 , The control of the level in the reservoir 13 done by the sensor 76 , The crusher plant 6 and the CO ₂ mill 12 are on the fixed plate 77 assembled. At the fixed plate 77 is the cold chamber 17 spring-suspended, so that the CO ₂ water ice mixture 18 by the swinging movements, by the vibrator 19 be generated, unhindered on the cooling plates 20 to the dosing unit 23 can slip and thereby through the cooling block 36 is cooled further to the desired temperature.

The cooling block 36 is made with the help of a special refrigerant mixture that passes through the refrigeration unit 34 is moved, cooled. The cooling blocks 4 are also mixed with a special refrigerant mixture that passes through the refrigeration unit 37 is moved, cooled.

The compressed air required for blasting is supplied via the nozzle 78 in the heating unit 79 guided and shared. The dosing flow 24 is unheated to the dosing unit 23 passed there and with the brought to cryogenic CO ₂ -water ice mixture 18 loaded. The beam current 25 gets in the heating unit 79 heated and in the mixing chamber 27 with the with the CO ₂ -water ice mixture 18 loaded dosing flow 24 merged and directed to the blasting gun (not shown).

During breaks, no CO ₂ water ice mixture 18 taken off, but the water ice dresser 1 continues to produce flake ice 2 , The motor 62 the drive shaft 33 is changed in its direction of rotation and the flap 66 at the transport unit 5 through the engine 82 open. The flake ice 2 falls into the water tank 80 , To avoid clogging the suction port of the pump 32 through flake ice 2 is a sieve 81 built-in. When the beam operation resumes, the direction of rotation of the motor becomes 62 changed again and shut up 66 closed.

From the foregoing, numerous advantages of the present invention have become apparent. Among them are especially to call: There is a blasting agent available, which combines the thermal benefits of CO ₂ -strahltechnik and the beneficial mechanical effect of solid water ice in itself.

By means of controllable shredding units, the size and the mixing ratio of CO ₂ - 16 and the water ice particles 15 can be adjusted and regulated according to the type of contamination.

The CO ₂ water ice mixture 18 can be adapted in its hardness and abrasiveness to the component to be cleaned and the contamination targeted.

The surfaces of the cleaned components are dry after cleaning and free from rust.

Particularly advantageous has been found that there is the possibility to clean with the blasting agent according to the invention and large components in the installed state, without a time-consuming installation and removal is required.

The CO ₂ water ice mixture 18 Can be used in conjunction with a specially prepared warm compressed air stream 22 , for cleaning unheated components, while maintaining a specific temperature difference between the component and CO ₂ -water-ice mixture 18 , are used.

By using the CO ₂ water ice mixture 18 in conjunction with a specially prepared warm compressed air stream 22 The formation of condensate, which is responsible for the occurrence of leakage currents, especially in electrical installations, can be avoided.

LIST OF REFERENCE NUMBERS

1

Water ice preparer

2

flake

3

conveyor belts

4

cooling blocks

5

transport unit

6

crusher plant

7

fan

8th

Upper neck

9

lower neck

10

baffle

11

small funnel

12

CO ₂ grinding plant

13

reservoir

14

CO ₂ pellets

15

water ice

16

CO ₂ particles

17

cold chamber

18

CO ₂ water ice mixture

19

Jogger

20

cooling plates

21

angle of attack

22

Main air stream

23

dosing

24

metered

25

beam current

26

air heating

27

mixing chamber

28

blasting gun

29

cleaning jet

30

Small conveyor belt

31

water tank

32

pump

33

drive shaft

34

refrigeration unit

35

cooling levels

36

cooling block

37

refrigeration unit

38

CO ₂ block

39

Insulated

40

water ice block

41

CO ₂ water ice mixture

42

CO ₂ shaft

43

Wassereisschacht

44

CO ₂ rasp

45

Water ice rasp

46

reservoir

47

CO ₂ particles

48

Water ice particles

49

isolation

50

rotary valve

51

rotary valve

52

cooling unit

53

hoppers

54

cooling plane

55

cooling coil

56

refrigeration unit

57

upper Kühlebene

58

gap

59

cooling pipe

60

agitator

61

double wall

62

pusher

63

idler pulley

64

jig

65

ribs

66

flap

67

baseplate

68

mounting plate

69

engine

70

toothed belt

71

support pole

72

fan

73

anvil strip

74

hammer shaft

75

Hammerrad

76

sensor

77

plate

78

Support

79

heating unit

80

water tank

81

scree

82

engine

83

frame

84

engine

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2003101667 A1 [0004]
• DE 10259132 B4 [0005]
• JP 60145905 A [0006]
• DE 3505675 A1 [0007]
• DE 102006002653 B4 [0008]
• DE 10010012 A1 [0009]
• US 5785581 [0010]
• DE 102010020618 A1 [0011]

Cited non-patent literature

• B. Karpuschewski et al., Basic Deburring Considerations as a Novel Method of Deburring Complex Components [0017]
• A. Momber, Surface Treatment Manual for Concrete [0017]

Claims (15)

Process for producing a blasting abrasive ( 18 ; 41 ) for blasting bodies, surfaces, interiors and the like, comprising CO ₂ and water, whereby CO ₂ and water are solidified, characterized in that first solid particles ( 14 . 16 ) from CO ₂ and second solid particles ( 2 . 15 ) are generated separately from water and then combined, in particular mixed. Method according to claim 1, characterized in that the first ( 16 ) and second particles ( 15 ) are produced by crushing and / or that the first ( 14 ) and / or second particles ( 2 ) are crushed before merging. Method according to claim 2, characterized in that the comminution of the first particles ( 14 ) at temperatures of -60 ° C to -80 ° C, preferably -70 ° C takes place and / or that the comminution of the second particles ( 2 ) at temperatures from -10 ° C to -40 ° C, preferably from -15 ° C to -30 ° C, in particular -25 ° C. Method according to one of the preceding claims, characterized in that the first particles ( 16 ) have a dimensioning of 0.4 mm to 1 mm, preferably 0.6 to 0.8 mm in the cross-sectional means and / or that the second particles ( 15 ) have a dimensioning of 0.6 mm to 1.2 mm, preferably 0.8 to 1.0 mm in the cross-sectional means, in particular flake ice is generated. Method according to one of the preceding claims, characterized in that the size and / or size distributions of the first ( 16 ) and the second particle ( 15 ) are set so that for the first ( 16 ) and second particles ( 15 ) each give the same masses or mass distributions and / or that the size of the first ( 16 ) and / or the second particle ( 15 ) in their production so much larger than that in the blasting agent ( 18 ) desired size is adjusted in order to produce the abrasive ( 18 ) compensate for size losses. Method according to one of the preceding claims, characterized gekennnzeichnet that the abrasiveness of the blasting agent ( 18 ; 41 ) by adjusting the mixing ratio between the first ( 16 ) and second particles ( 15 ), the shape of the second particles ( 15 ), the size of the second particles ( 15 ) and / or the temperature of the second particles ( 15 ) in the blasting medium ( 18 ) and / or that the resulting after merging CO ₂ gas is used as a protective gas against heating and ambient air and / or for cooling the second particles ( 15 ) is used. Method according to one of the preceding claims, characterized in that for cooling the second particles ( 15 ) CO ₂ snow, liquid nitrogen and / or frozen compressed air are used and / or that the first and second particles are stored separately from each other before the merger so that an at least partial temperature exchange can take place. Method according to one of the preceding claims, characterized in that the first particles, the second particles ( 2 ) and / or the blasting agent ( 18 ) in two or more cooling levels ( 4 . 10 . 20 ) is cooled. Method for blasting bodies, surfaces, interiors and the like, characterized in that a blasting medium ( 18 ; 41 ) prepared according to one of the preceding claims. A method according to claim 9, characterized in that for the dosage of the blasting agent ( 18 ; 41 ) a dried fluid stream, in particular compressed air stream, is used as metering stream and / or the blasting medium ( 18 ; 41 ) is acted upon as a jet stream having a temperature of + 40 ° C to + 90 ° C, preferably + 50 ° C to + 90 ° C, in particular + 70 ° C to + 80 ° C with a dried fluid stream, in particular compressed air stream , Blasting agent for blasting bodies, surfaces, interiors and the like, comprising solidified CO ₂ and solidified water, characterized in that the blasting agent ( 18 ; 41 ) was prepared by a method according to any one of claims 1 to 8. Device (A; B; C; D) for producing a blasting medium ( 18 ; 41 ) for blasting bodies, surfaces, interiors and the like, comprising solidified CO ₂ and solidified water, characterized in that feeding means ( 30 . 5 . 13 ) for separately generated first solid particles ( 14 ) from CO ₂ and second solid particles ( 2 ) are provided from water and in particular a mixer ( 17 ) for the first ( 15 ) and second particles ( 15 ). Device (A; B; C; D) according to claim 12, characterized in that the device is adapted to carry out a method according to one of claims 1 to 8. Apparatus for blasting bodies, surfaces, interiors and the like, comprising means for providing a fluid flow, in particular compressed air flow, and means for providing an abrasive, characterized in that the means for providing the blasting means as device (A; B; C; D ) for producing a blasting medium ( 18 ; 41 ) is designed according to one of claims 12 or 13. Apparatus according to claim 14, characterized in that dosing means for metering the blasting agent ( 18 ; 41 ) are provided which use a dried fluid stream, in particular compressed air stream, as a metering stream and / or that irradiation means for impinging the object to be blasted with the blasting agent ( 18 ; 41 ) are provided which use a dried fluid stream, in particular compressed air stream, as a jet stream having a temperature of + 40 ° C to + 90 ° C, preferably + 50 ° C to + 90 ° C, in particular + 70 ° C to + 80 ° C has.

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