RU2748313C1 - Method for feeding bulk solid cryogenic substance into compressed air stream and device for its implementation - Google Patents

Abstract

FIELD: cleaning.

SUBSTANCE: invention relates to a device for cleaning surfaces from contamination. The device is made with the possibility of feeding granules of solid cryogenic substances from the hopper into the compressed gas stream. The device contains a housing made with inlet and outlet channels for the compressed air flow. The bottom seal is hermetically sealed in the body. The portion shaft is installed in the lower seal and is rotatable. The portion shaft is provided with a peripheral surface in which a plurality of spaced slots is formed. A through longitudinal channel is made in the lower seal, made with possibility of ensuring unobstructed flow of compressed air along the portion shaft from the inlet channel to the outlet channel, ensuring that granules of solid cryogenic substances are washed out of the slots of the portion shaft due to the vortex motion of compressed air. The through longitudinal channel is bounded at the bottom by the housing and at the sides by the lower seal, and at the top by the portion shaft. The inlet channel is made in such a way that the axis of the inlet channel is located perpendicular to the axis of the through longitudinal channel of the lower seal and is offset relative to the axis of the through longitudinal channel along the vertical plane.

EFFECT: increased reliability and productivity of the dry ice cleaning process.

15 cl, 12 dwg

Description

Technology area

The claimed invention relates to mechanical engineering, in particular to devices for cleaning surfaces from contamination, and can be used in various fields of industry: automotive, aircraft, shipbuilding, nuclear industry, foundry, mechanical engineering, chemical and oil and gas, food, printing, light, energy and electronics. Namely, for cleaning pumps and tanks, oilfield equipment; removal of various organic coatings and contaminants (varnishes, paints, oils, wax, mastic, mold, algae, glue, soot and other deposits); cleaning from rust; removing graffiti from walls; cleaning of electrical equipment: generators, electric motors, fans, compressors, radiators, printed circuit boards; cleaning of molds, molds, core boxes in the foundry industry; cleaning of car parts at car washes; cleaning of processing equipment in the food industry; removal of radioactive contamination. In this case, the surface to be cleaned can be metal, glass, plastic, rubber, brick, etc.

State of the art

Dry ice cleaning is used effectively in a wide variety of applications, from slag removal to cleaning of printed circuit boards. This cleaning method can be successfully used for operating equipment without damage and dismantling, which significantly reduces its downtime.

Unlike conventional toxic chemicals, high pressure water and abrasive blasting, cryogenic blasting uses dry ice particles in a high velocity air stream. At the same time, there are no technological inconveniences associated with the processing of secondary raw materials and waste disposal. The physics of the carbon dioxide purification process is as follows. The dry ice particles are accelerated in the carrier, which is compressed air. In this respect, dry ice blasting is similar in principle to sandblasting. Since dry ice has a relatively low density, the process relies on a high particle velocity to obtain the required impact energy. When it collides with a surface, dry ice sublimes (evaporates), with an extremely rapid heat transfer process between the ice granules and the surface. No moisture is formed when dry ice evaporates. The gas then expands hundreds of times the volume of granular dry ice within a few milliseconds, causing a micro-explosion at the point of impact, causing the pollution to break down. Due to the large temperature difference between the ice particles and the surface to be cleaned, heatstroke also occurs, destroying the contaminating coating. This phenomenon is especially pronounced when processing a non-metallic coating, for example, paint and varnish on a metal substrate.

Shot blasting systems have been around for decades. Typically, the particles are fed into the transport gas stream and transported as entrained particles to a blowing nozzle, from which the particles exit towards a preform or other target.

A device for blasting with dry ice is known from the prior art (WO 2015040072 A1, publ. 03/26/2015). The device contains a compressed air supply means, which is made in the form of a compressed air supply line and a control controller for controlling the flow rate and pressure of the compressed air flow in the compressed air line in a closed and / or open mode; a device for storing and supplying dry ice and a wheel for combining compressed air from the compressed air line with a certain amount of dry ice to obtain a mixture of compressed air and dry ice. A device for creating a turbulent flow in the compressed air flow is located in the area of the compressed air line between the control controller and the wheel lock.

From the prior art (US 4389820 A, publ. 1983-06-28) known shot blasting machine using sublimated particles. The known device includes a molding means for producing particles having substantially the same length, a metering means for receiving particles and for introducing particles into a gas stream for transporting low pressure, and a nozzle for accelerating the particles and providing an associated low velocity gas flow. and high pressure. The nozzle is configured to convert a low velocity, high pressure gas stream into a high velocity, low pressure gas stream. A conduit connected to the nozzle and metering means receives the particles and injects the particles into a high-velocity, low-pressure gas stream within the nozzle, which captures the particles and accelerates them to a high exit velocity.

A device for jet cleaning with granules is known from the prior art (US 4947592 A, publ. 1990-08-14). The known device comprises a housing defining an internal cavity having spaced apart stations for receiving and unloading granules, and a radial transport rotor for transporting granules from the receiving station to the unloading station. The radial transport rotor further includes a plurality of transport cavities, each of which is formed on a peripheral surface of the radial transport rotor for receiving pellets for radial movement between the receiving and unloading station. The receiving station communicates with the source of the freeze-dried granules.

Many devices known from the prior art are made with rotating rotors made with cavities or pockets for transporting granules into the transported gas stream. In contact with the surface of the rotor, body parts are used, which are seals. The seals have cavities or pockets. Such seals usually press against the rotor surface, whether the rotor is spinning or the system is running. The force of the seal leads to the resistance of the seal, creating a moment of resistance that must be overcome by the motor rotating the rotor. When torque is transmitted to rotate the rotor, a significant starting load increases on the motor, affecting the size and wear of the motor. Prior art large diameter rotors also provide significant torque arm through which the seal resistance creates significant torque.

The rotors known from the prior art have pockets formed on the peripheral surface of the rotor. The disadvantage of the known rotors is the incomplete discharge of the granules from the pockets. In addition, the distance between the pockets and the lack of thorough, uniform mixing of the transport gas and granules in the feeder leads to impulses.

The essence of the invention

The problem solved by the claimed invention is to create a reliable and high-performance device for cleaning dry ice, which will ensure the maximum discharge of dry ice pellets from the pockets.

The technical result of the claimed invention is to increase the reliability and increase the productivity of the dry ice cleaning process, by increasing the consumption of dry ice granules with a portioned shaft with the same working area, as well as by crushing the granules in the mixing area due to the vortex flow of compressed air, and reducing risk of clogging due to large air flow channels.

Reliability depends on reducing the risk of clogging of dry ice granules with its particles of narrow spaces and flow sections in the unit for feeding granules into the compressed air path and the critical section of the nozzle (1) for cleaning. Dry ice pellets used for cleaning are traditionally 3 mm in diameter and 15-30 mm in length, which can lead to clogging.

The cleaning performance is influenced by the flow rate of the granules in the compressed air path. Therefore, with the same working area of the portion shaft, the flow rate can be increased due to the optimal number and volume of each slot, but the main indicator is the rotation speed of the portion shaft. In this case, the higher the rotation speed, the less time the groove with the granules stays in the air flow area, therefore, to ensure proper washing out of the granules from the grooves, a more intense air flow is required, which rushes into the grooves and washes out the granules.

Also, the risk of clogging and the speed of cleaning is influenced by the presence of bottlenecks through which air flows, since air usually has humidity, then moisture tends to turn into water ice in contact with dry ice granules, which grows on the surfaces of narrow slots and thereby reduces the throughput section, which leads to an increase in hydraulic resistance and a decrease in the pressure (aggressiveness) of cleaning.

The technical result of the claimed group of the invention is achieved due to the fact that a device for feeding a free-flowing solid cryogenic substance into a compressed air stream, configured to supply granules of a cryogenic solid substance from a bunker to a compressed gas stream, containing a housing made with inlet and outlet channels for a compressed stream air, a lower seal hermetically installed in the housing, a portion shaft installed in the lower seal and made with the possibility of rotation around the axis of rotation, while the specified portion shaft is made with a peripheral surface in which a plurality of spaced slots are formed, and a through longitudinal channel is made in the lower seal , made with the possibility of ensuring the unhindered flow of compressed air along the portion shaft from the inlet channel to the outlet channel, ensuring the washing out of granules of solid cryogenic substance from the slots of the portion shaft due to the vortex movement of compressed air, while the through the single channel is bounded from below by the housing and on the sides by the lower seal, and from above by the portion shaft, while the inlet channel is made in such a way that the axis of the inlet channel is located perpendicular to the axis of the through longitudinal channel of the lower seal and is offset relative to the axis of the through longitudinal channel along the vertical plane.

In the particular case of the implementation of the claimed technical solution, the input and output channels are made in such a way that the axes of the channels are offset relative to each other in the horizontal plane.

In a particular case, the implementation of the claimed technical solution is made with two input channels.

In the particular case of the implementation of the claimed technical solution, the inlet channel and the through longitudinal channels are made in such a way that they provide the movement of the compressed air flow with a double change in the direction of the flow, while the transition from channel to channel is made with radii of curvature.

In the particular case of the implementation of the claimed technical solution, the input and output channels, as well as the through longitudinal channel, are made with a variable section and / or shape along the length of the channel.

In the particular case of the implementation of the claimed technical solution, passive grooves are made in the lower part of the lower seal, connected to the channel for the compressed air flow.

In the particular case of the implementation of the claimed technical solution, the lower seal is made with a continuous closed groove along its peripheral surface in which an o-ring is installed.

In the particular case of the implementation of the claimed technical solution, it additionally contains an upper seal installed on the lower seal and made with a surface in contact with the peripheral surface of the portion shaft and equipped with a cover, in which there are additionally installed means for mixing granules of solid cryogenic substances, performing reciprocating actions due to pneumatic cylinders.

In the particular case of the implementation of the claimed technical solution, the portion shaft is made with two rows of circumferential grooves, with each circumferential row containing six slots.

In the particular case of the implementation of the claimed technical solution, the grooves in the portion shaft are aligned with an angular displacement of 360 degrees around the axis and have the form of an extruded prism subtracted from the portion shaft body along the portion shaft axis, while the axial and circumferential rows are arranged in such a way that the axial and circumferential width grooves overlap, but do not intersect with each other.

In the particular case of the implementation of the claimed technical solution, the portion shaft is mounted on bearings, and the portion shaft is rotated due to a gear motor, with which the portion shaft is connected through an elastic coupling.

In the particular case of the implementation of the claimed technical solution, the bearings are installed in the walls located on the end surfaces of the supply unit housing, while a cover is made in one wall to ensure the possibility of removing the portion shaft in the direction opposite to the gear motor.

The technical result of the claimed group of the invention is also achieved due to the fact that the method of supplying a free-flowing solid cryogenic substance into a compressed air stream includes the stages at which granules of a solid cryogenic substance are fed into the area above the portion shaft; feed the granules into the grooves of the portion shaft; provide constant rotation of the portion shaft and move the granules of the solid cryogenic substance to the area under pressure; compressed air is fed into the granule feed unit to ensure the movement of the compressed air flow with a double change in the direction of the flow, and a swirl of the compressed air flow is created and the granules of solid cryogenic substance are washed out of the grooves of the batch shaft with a vortex flow of compressed air, while the pressure is created in the passive grooves of the lower seal and provide a hermetically sealed batch shaft.

In the particular case of the implementation of the claimed technical solution, the movement of the compressed air flow along a horizontal straight line is provided, then a sharp turn towards the vertical direction is provided and a sharp turn towards the horizontal direction is carried out.

In the particular case of the implementation of the claimed technical solution, the flow is rotated by 90 degrees.

Brief Description of Drawings

Details, features, and advantages of the present invention follow from the following description of embodiments of the claimed technical solution using the drawings, which show:

FIG. 1 depicts a mobile dry ice cleaning device;

FIG. 2 is a general view of a mobile dry ice cleaning device;

FIG. 3 - shows a disassembled granule feed unit with a geared motor;

FIG. 4 - shows a disassembled granule feeding unit;

FIG. 5 - shows a section of the housing of the granule feed unit with the installed bottom seal and the portion shaft;

FIG. 6 - shows a top view of the granule feed unit and the gear motor;

FIG. 7 shows a view a-a and b-b of FIG. 6;

FIG. 8 is a view C-C of FIG. 6;

FIG. 9 shows a variant with two input and one output channels, while the input channels given in this embodiment of the technical solution can be made as output channels, and the output channel is made in the form of an input channel;

FIG. 10 shows a variant of the direction of the compressed air trajectory in the granule supply unit;

FIG. 11 shows a variant of the direction of the compressed air trajectory in the granule supply unit;

FIG. 12 depicts vortex streamlines of medium motion for the present invention with a wide channel. Isometry.

The figures in the figures indicate the following structural elements:

1 - nozzle; 2 - quick disconnect connection; 3 - handle; 4 - quick disconnect connection; 5 - handles of the mobile installation; 6 - a mobile unit containing a device for cleaning with dry ice; 7 - hatch; 8 - control panel; 9 - power plug; 10 - slit; 11 - controls; 12 - trigger; 13 - quick disconnect connection; 14 - jet hose; 15 - control cable; 16 - quick disconnect connection; 17 - quick disconnect connection; 18 - wheels with a rotary stopper; 19 - removable doors; 20 - pneumatic wheels; 21 - quick-disconnect connection for jet hose connection; 22 - granule feeding unit; 23 - flexible hose for feeding granules from the hopper; 24 - pressure regulator; 25 - storage bin for granules; 26 - hopper suspension; 27 - quick disconnect connection; 28 - filter; 29 - nipple for connecting the air source; 30 - case; 31 - inner wall; 32 - outer wall; 33 - bearings; 34 - sealing ring; 35 - bottom seal; 36 - upper seal; 37 - portion shaft; 38 - cover; 39 - plate; 40 - pipe; 41 - glass; 42 - clutch; 43 - drive shaft; 44 - gear motor; 45 - insert; 46 - insert cover; 47 - fitting; 48 - pneumatic cylinder; 49 - bushing; 50 - bumper; 51 - the outer cylindrical surface of the portion shaft; 52 - portion shaft groove; 53 - peripheral surface of the lower seal; 54 - continuous closed groove; 55 - the inner surface of the body; 56 - cylindrical surface; 57 - passive grooves; 58 - through channel; 59 - input channel; 60 - output channel; 61 - holes for fastening; 62 - chamfer; 63 - shank; 64 - direct direction of compressed air flow; 65 - vertical direction of compressed air flow; 66 - horizontal direction of compressed air flow; 67 - wall.

Disclosure of invention

In general, the device for feeding a free-flowing solid cryogenic substance into the compressed air stream can be made stationary, or can be made as a mobile unit. An example of such a mobile installation is shown in FIG. 1 and FIG. 2. The description below shows an example of such a mobile installation.

The mobile device is made on a frame mounted on wheels. Inside, in the upper part of the frame, there is a hopper (25) for storing granules of solid cryogenic substances and a supply unit (22) for granules. The feed unit (22) of granules is connected to the hopper (25) by means of a flexible hose (23). The hopper (25) is fixed to the frame by means of hangers (26).

The installation is made with the possibility of supplying compressed air to the granule feeding unit (22). For this purpose, the unit is equipped with branch pipes located inside the unit. The unit is equipped with a nipple (29) for connecting a compressed air source. The nipple is connected to the filter (28) by means of a pipe. A filter (28) is required to filter and remove condensed moisture from the compressed air. In this case, the branch pipes and the filter (28) are equipped with a quick-disconnect connection (27) for removing the filter. To regulate the pressure of the incoming compressed air into the granule feeding unit (22), the installation is equipped with a pressure regulator (24), which ensures the regulation of the cleaning aggressiveness. The unit is also equipped with a pneumatic quick-release connection (21) for connecting the jet hose (14). A quick-release connection (21) is installed at the outlet of the supply unit (22) of cryogenic solid granules. The trajectory of compressed air flow inside the mobile unit: (29-28-24-22-21).

The jet hose (14) is connected to the nozzle (1) and is required to supply a mixture of compressed air with granules of solid cryogenic substances to the nozzle (1). The nozzle (1) is held and guided by the operator for cleaning using the handle (3), which houses the controls (11) and the trigger (12) to start cleaning. For quick change of nozzles, connection of the jet hose and control cable (15), the handle is equipped with a quick-release connection (2), (4), (13), (16) and (17). The mobile unit has a control panel (8), a power plug (9). The wheels of the mobile unit are made of two types - swivel wheels with a stopper (18) and power pneumatic wheels (20). Removable doors (19) are located on the sides of the mobile unit.

Granules of solid cryogenic substance through the hatch (7) are put into the hopper (25) and through the flexible hose (23) are fed to the feed unit (22). Compressed air is also connected to the feed unit. Inside the supply unit (22) granules of solid cryogenic substances are mixed with compressed air, then the mixture is fed through the jet hose (14) to the nozzle (1). In the nozzle (1), the granules are accelerated by a fast air flow and fly out of the slot (10).

The following is a detailed description with reference to FIG. 3 to FIG. 9 of the granule feeding unit (22), which is a device for feeding a free-flowing solid cryogenic substance into a compressed air stream. The design of the pellet feeding unit (22) is the subject of the present invention.

The body (30) is the basic element of the structure of the granule feeding unit, carries the power load and passes compressed air through itself, sets the first rotation of the air flow. The body (30) is made of metal, in particular aluminum.

The housing (30) has an inlet channel (59) for supplying compressed air and an outlet channel (60) for supplying the mixture by means of hoses to the nozzle (1). Nipples (47) are connected to the inlet (59) and the outlet (60), for example by welding. A branch pipe for supplying compressed air and a jet hose (14) are connected to the fittings (47) of the inlet and outlet channels by means of quick-release couplings, respectively.

In this case, in the embodiment of the claimed technical solution, a jet hose (14) can be connected to the fittings of the inlet channel (59) and the inlet channel (59) in this embodiment of the claimed technical solution will be the output channel, and to the fitting (47) of the outlet channel (60) with this embodiment of the claimed technical solution, a compressed air supply pipe is connected.

Also, another embodiment of the claimed invention is shown in FIG. 9. In this embodiment of the claimed technical solution, two inlet channels (59) are made, to which the compressed air supply pipes are connected through the fitting, and the outlet channel (60) in this embodiment is one, to which the jet hose is connected through the fitting. Also, these two inlet channels (59) can be connected to two jet hoses (14) and be the outlet channels, and the outlet channel in this case is connected to the compressed air supply pipe and is the inlet channel.

Holes (61) are made in the body, which are necessary for screwing in the screws, by means of which the outer (32) and inner walls (31) are fixed on the body (30).

A lower seal (35) is installed in the upper part of the housing (30). The lower seal (35) is connected to the upper seal (36) to form an inner cylindrical cavity in which the portioning shaft (37) is installed.

The body (30) is connected in the inner (31) and outer (32) walls. The inner wall (31) is bolted to the housing (30) and carries the compressed air load and holds the bearing (33), bears the torque load transmitted from the geared motor (44). The outer wall (32) is bolted to the housing (30), carries the compressed air load, holds the bearing (33); allows you to pull out the portion shaft (37); holds the insert (45). In an embodiment of the claimed technical solution, the outer (32) and inner (31) walls of the body (30) are made of metal, in a particular case, of aluminum.

The housing (30) is connected to the geared motor (44) by means of a glass (41). On the one hand, the glass (41) is connected to the housing of the mentioned gear motor (44), and on the other hand, it is connected to the inner wall (31). Cup connections are made by means of a bolted connection.

The clutch (42) on one side is connected to the drive shaft (43) of the geared motor (44) and is fixed on it in the axial and angular position by bolts, and on the other side is connected to the shank (63) of the portion shaft. The specified connections of the coupling with the shank of the portion shaft and with the drive shaft of the gear motor are made inside the glass (41). The clutch (42) transfers torque from the drive shaft (43) to the shank (63) of the batch shaft (37). The clutch (42) locks the portion shaft (37) in an axial position on one side.

The geared motor (44) is powered by electricity or compressed air to generate rotation of the drive shaft (43) at the required torque to turn the portion shaft (37) at a certain compressed air pressure flowing under the bottom seal (35).

The portion shaft (37) is rotatably held by bearings (33) installed in the outer and inner walls for rotation (33) by the motor reducer (44) around the axis of the portion shaft (37).

The portion shaft (37) is connected with one end by means of the shank (63) to the coupling (42), which is connected to the drive shaft (43) of the gear motor (44). The other end of the portion shaft (37) is inserted into the inner ring of the bearing (33) installed in the outer wall (32). A bearing (33) installed in the outer wall (32) is closed by a cover (46) through an insert (45). The liner is made of fluoroplastic. The fit between the bearings and the batch roll allows the batch roll to be easily removed from the pellet feed unit by removing the liner retaining cap (46) and insert (45), and slide the batch roll (37) through the bearing (33). The portion shaft (37) has an axis of rotation and an outer cylindrical surface (51), at least one groove (52) is located on the surface 360 degrees in at least one row. At one end, the portion shaft (37) contains a shank (63) for taking the moment from the clutch (42). A threaded hole is made at the other end of the portioning shaft (37) to provide a recess. A threaded shaft, for example a bolt, can be inserted into said threaded hole to facilitate removal of the portion shaft.

The lower seal (35) has on its peripheral surface (53) a continuous closed groove (54) in which the sealing ring (34) is installed. The ring (34) is compressed between the lower seal (35) inside the groove (54) and the inner surface (55) of the housing (30), thereby preventing the flow of compressed air from under the lower seal. The upper part of the lower seal (35) has a partially cylindrical surface (56), which presses the seal against the portioning shaft (37). In the lower part of the lower seal (35), longitudinal passive grooves (57) are made, in which air does not move, they are necessary to increase the pressure area.

Longitudinal passive grooves are made inside the lower seal along the cylindrical surface (56) and are separated from the said surface by a wall (67). A through channel (58) is made between the longitudinal passive grooves in the lower seal (35) through which the main flow of compressed air moves from the inlet channel (59) to the outlet channel (60) of the housing (30). The channel (58) passes through the body of the seal (35) and intersects with the surface (56), thereby forming a through window on the cylindrical surface (56) of the lower seal (35) for the compressed air to flush out the granules from the grooves (52) of the portion shaft (37) ... The lower seal (35) is partially located in the cavity of the body (30), and the seal ring (34) is located in the groove (54), sealingly interacting with the groove and the inner wall of the body (30). The lower seal (35) includes a surface (56) that, when assembled, contacts the peripheral surface (51) of the portioning shaft (37) to form a seal therewith. The lower seal (35) seals the portioning shaft (37) by compressed air pressure, thereby preventing the compressed air from penetrating the area above the portioning shaft (37); sets the second turn of the air flow, which leads to the creation of a vortex flow under the portion shaft (37).

The ring (34) is compressed with the lower seal (35) installed in the housing (30) and prevents air from escaping from the lower seal (35). The ring (34) is made of an elastic material, in particular of rubber.

The housing (30) is made with a chamfer (62) along the perimeter of the upper part of the housing (30) for simplified installation of the lower seal (35) with the fitted seal ring (34).

Referring to FIG. 5 to FIG. 9 for clarity of explanation, as described above, the lower seal (35) is located partially in the housing (30). Moreover, the lower seal (35) is installed with the inner surface (55) of the housing (30) hermetically. The tightness between the bottom seal (35) and the inner surface (55) of the body (30) is ensured by the installed O-ring (34) in a continuous closed groove (54). A continuous closed groove (54) is made along the peripheral surface (53) of the lower seal (35).

The wall (67) of each longitudinal passive groove (57) of the lower seal (35) is spaced from the cylindrical surface (56) of the lower seal (35), and together they form an arcuate wall (67). The arcuate wall (67) is a relatively thin wall between the cavity of each passive groove (57) and the cylindrical surface (56) of the lower seal (35).

The arcuate wall (67) is flexible enough to transfer a significant part of the pressure exerted on the surface of the wall (67) from the side of the cavity of each passive groove (57) to the surface (51) of the portion shaft (37) by the surface (56). As the compressed air flows through the compressed air channel (58), the compressed air pressure in each passive groove (57) presses against the surface of the wall (67), pressing the surface (56) against the surface (51) of the portioning shaft (37). The flexibility of the arcuate wall (67) allows the arcuate wall to conform to the shape of the docking roll (37) surface (51) and transfer a significant portion of the pressure to the docking roll (56) surface, causing the 56 to seal contact with the docking roll surface (51).

In the illustrated embodiment, the sealing surface (56) contacts the surface (51) of the portion shaft (37) at an angle of about 180 °.

The configuration depicted allows the sealing force to be applied over substantially the entire contact angle and substantially normal to the surface (51) of the batch shaft (37). Of course, other sealing devices can be used, even those which are not driven by compressed air when the passive slots (57) are part of the transport gas stream.

It is noted that as the compressed air pressure increases, the required sealing force between the surface (51) of the portion shaft (37) and the surface (56) of the lower seal (35) increases. In the illustrated embodiment, the sealing force between the surface (51) of the portioning shaft (37) and the surface (56) is proportional to the compressed air pressure. In turn, the load on the portion shaft (37) and the geared motor (44) is proportional to the pressure of the transported gas. This reduces rotor and seal wear and increases engine life.

Although in the illustrated embodiment, in the flow path, compressed air presses the surface (56) of the surface (51) of the batch air (37), the pressure driving the seal against the surface (51) of the batch shaft (37) can come from any source.

The portion shaft (37) is made of hard anodized aluminum and is depicted as a cylinder, although other shapes such as tapered and other materials such as stainless steel may be used.

Bearings (33) installed in the outer (32) and inner (31) walls hold the portion shaft (37) while rotating, while the portion shaft is installed with a guaranteed clearance along the inner ring of the bearings (33).

In the illustrated embodiment, the portioning roller (37) has a diameter of 40 mm. The present invention involves the use of a portion roll (37) having a diameter of approximately 40 mm.

The portion shaft (37) includes a peripheral surface (51) in which a plurality of spaced slots (52) are formed. In the embodiment shown, there are two circumferential rows of slots (52), with each circumferential row having six slots (52).

The grooves (52) are aligned with an angular displacement of 360 degrees around the axis and have the form of an extruded prism subtracted from the body of the portion shaft (37) along the axis of the portion shaft (37); also, the grooves (52) can be represented in the video of holes of other shapes. The axial and circumferential rows are arranged in such a way that the axial and circumferential widths of the grooves (52) overlap, but do not intersect with each other.

In the illustrated embodiment of the feed unit, there is no axial load on the batch shaft, neither on the seal side nor on the bearing side.

The upper seal (36) also includes a surface that, when assembled, contacts the peripheral surface (51) of the portion shaft (37). The upper seal (36) covers the portioning shaft (37) by being held in place by a cover (38). There is always a small gap between the shaft and the upper seal, which is several times smaller than the size of the granules; nothing presses on the seal from above. The upper seal prevents the dry ice pellets from spilling out of the cryogenic solid pellet feed unit (22) and guides the cryogenic solid pellets into the grooves (52) of the batch roll (37). The upper seal (36) is closed from above with a cover (38), thereby closing the walls and forming a single power and sealed structure.

A plate (39) is attached to the cover (38). A hole is made in the plate and the cover. A pipe (40) is attached coaxially to the hole to the plate (39), thereby organizing an entrance for granules of solid cryogenic substances into the granule supply unit (22). The fastening can be done by welding, for example.

In this case, bumpers (50) are installed inside the cover (38). Bumpers (50) Serve for crushing lumps of adhered granules, which are formed from moisture during long-term or poor-quality storage of granules, as well as during cleaning breaks when the bin is full. To install the bumpers, holes are made in the side surface of the cover (38) into which the bumpers (50) are installed. Bumpers (50) reciprocate due to pneumatic cylinders (49) connected to bumpers (50) through bushings (48). Bushings (48) serve to reduce heat flux from the cover (38) to the pneumatic cylinders (49).

In general, in an embodiment of the claimed technical solution, the granule feeding unit (22) can be made without an upper seal. In this variant, there will be an overconsumption of granules of a solid cryogenic substance due to their pouring out of the granule supply unit. In this case, the technical result will be achieved in the same way as when using the upper seal.

The cryogenic solid granules are fed from the granule storage hopper (25) by means of a flexible hose (23) connected to the pipe (40) to the granule feeding unit (22), where they fall into the grooves (52) of the portion shaft (37). The portion shaft (37), with constant rotation, receives granules of solid cryogenic substance from above, and from below, the granules free the grooves (52) due to the vortex air flow.

The upper seal (36) and the lower seal (35) are made of an antifriction structural material such as graphite-filled PTFE or high molecular weight polyethylene. The ends of the seal surfaces adjacent to the bearing (33) mounted in the outer wall (32) are chamfered to facilitate the installation of the portion shaft (37).

The entire structure of the feed unit (22) of granules is made to facilitate the replacement of rubbing components during maintenance or repair. In the absence of compressed air, the worn or damaged portion shaft (37) is pulled out through the bearings, the top cover and top seal are removed, and the worn or damaged bottom seal is pulled out. In the reverse order, worn or damaged parts are replaced to restore the operation of the pellet feed unit.

The supply unit (22) of granules of solid cryogenic substance contains a transport gas channel made from the inlet channel (59) to the outlet channel (60), while the axes of the inlet and outlet channels are made perpendicular to the axis of the through longitudinal active groove of the lower seal, and the axes of the inlet and the outlet openings are displaced relative to the axis of the active groove in the vertical plane and are displaced relative to each other in the horizontal plane.

Compressed air flows under the portion shaft (37) and along it through the through channel (58) freely from the inlet channel (59) to the outlet channel (60) in any position of the portion shaft (37). The compressed air flows under the portion shaft (37) even if there were no grooves in the portion shaft or if the grooves were not in the lower position in some position of the shaft.

The granules are washed away from the vortex flow of compressed air, which expands when the groove (52) in the portion shaft (37) coincides with the through channel (58) of the lower seal (35).

The vortex effect is carried out due to the inlet channel (59): at the beginning of the path, the flow moves along a horizontal straight line (64), then a sharp turn by about 90 degrees towards the vertical direction (65), a sharp turn by about 90 degrees towards the horizontal direction (66 ).

In this case, the direction (64) is provided due to the inlet channel (59), the first rotation (64-65) due to the dead end, and the second rotation (65-66) due to the through channel (58) of the lower seal (35). In this case, the channel in the direction (66) is limited from below by the housing (30), on the sides by the seal (35), and from above by the portion shaft (37).

In the passive grooves (57) of the lower seal (35) there is no air movement, due to which there is a maximum degree of pressing of the walls (67) of the lower seal (35) to the peripheral surface (51) of the portioning shaft (37). In contrast to the analogue, in which air movement occurs in the chambers, and according to the Bernoulli equation, a pressure drop occurs.

As shown in FIG. 5, Fig. 7 into the inlet channel (59) communicates with the outlet channel (60) of compressed air through the through channel (58). In this case, the incoming compressed air flow is wrapped around and creates a vortex flow under the portion shaft (37). The vortex flow of compressed air promotes increased washout of particles from the grooves (52) of the portion shaft (37) and their fracture, which reduces the risk of clogging the critical section of the nozzle (1) for cleaning. An example of such a swirl is shown in Figure 12.

For example, at a shaft speed of 100 rpm with a shaft diameter of 40 mm, the peripheral speed of the shaft or slot inlet is approximately 0.2 m / s. With a channel width of 16 mm and a slot width of 10 mm, the opening and closing time of the channel is approximately 0.13 seconds. In this case, the air flow rate, for example, at 7 atm. and a flow rate of 5000 nl / min in a channel with a cross-sectional area of 256 sq. mm can be approximately 46 m / s. If the length of the working part of the shaft is 80 mm in length, then the air travels this distance in about 0.003 seconds, that is, 43 times the air flow has time to renew itself from the moment of opening until the moment of closing the groove in the shaft.

Unlike analogs, for the implementation of this system, it is not required to specifically direct the flow of the medium or part of the flow of the medium into the grooves or pockets, since, due to the swirling of the medium, it itself enters and washes the inner surface of the grooves (52) of the portion shaft (37) with the vortex streamlines.

In the present invention, the flow of the medium exits with a sharp double change in its channel to create a vortex in a three-coordinate system. A detailed description of the flow direction is given below.

The following description is explained in FIG. 12. If we take the X axis as the axis of the portion shaft (37), then for the maximum vortex effect, first the flow of the medium should move along the Y axis, then abruptly change direction to the Z axis, then sharply change to the X axis, due to which a vortex will be created ...

In this case, the distance between the turning points of the flows from Y to Z and from Z to X should not exceed ten sizes of the equivalent diameter of the channel (58) under the portion shaft (37).

The flow swirl is explained by the centrifugal force, at the first sharp turn the flow is swirled in the plane in which a sharp turn is carried out, and then the swirling flow continues to rotate by inertia, but at the same time, due to the second sharp transition, it goes to the side along the X axis under the portion shaft (37 ) and thus creates a vortex flow.

Thus, the design of the feed unit (22) directly affects the claimed technical result, since it provides two abrupt changes in the flow of the medium up to 180 degrees, if necessary, at each change in the flow.

In this application, the diameter of the shaft is 40 mm, although it can be of other sizes: the desired size is from 35 to 50 mm, the allowable is from 20 to 100 mm.

The nominal diameter of the flow sections is a theoretical value that cannot be measured, but it affects the flow regime of the medium (speed, turbulence). Formula for calculating the nominal diameter of the channel cross-section: the root of the division of four times the cross-sectional area by the number Pi.

Channels can be non-prismatic and change geometry along the channel. In this case, the nominal diameter will be calculated as the average over the length of the channel.

In this case, the compressed air flow in the vertical direction (65) can consist of parts of the compressed air flow in the forward direction (64) and the compressed air flow in the horizontal direction (66) as in FIG. 10, or the compressed air flow can have its own independent vertical direction (65) as in FIG. eleven.

The nominal diameter of the paths (64, 65, 66) is 20 mm, although the desired size is from 15 to 25 mm, the allowable size is from 5 to 50 mm.

The length of the trajectory (64 and 65) is not limited, but the length of the trajectory (66) is an important parameter, since it sets the vortex arm, the length of the trajectory (65) is 20 mm, although the desired size is from 15 to 35 mm, the allowable size is from 10 to 50 mm.

A sharp turn is allowed when going from channel to channel, but radii of curvature as in the current assembly can also be provided to help the air begin to curl and reduce resistance from the dead-end wall. In this case, the radius in this assembly is 20 mm, although the desired size is up to 35 mm, and the allowable size is up to 50 mm.

When the length (66) is longer than 50 mm or shorter than 5 mm, and the radius of curvature (64-65) is also higher than 50 mm, then the effect of curling the flow will be lost.

When the nominal diameter of the trajectories (64, 65, 66) is below 5 mm, the hydraulic resistance will be too high and the cleaning pressure (aggressiveness) will decrease, and if it is more than 50 mm, then the vortex velocity will be low in order to effectively flush out the granules from the grooves. This invention relates to air sources with flow rates from 1000 Nl / min to 20,000 Nl / min.

As seen in FIG. 10 and FIG. 11 lines (64) and (66) are crossing, this is an important point, since otherwise line (65) degenerates into a point.

The angle between the crossing lines (64) and (66) is also important, for this design it is 90 degrees, although the desired size is from 60 to 120 degrees, the allowable is from 30 to 160 degrees.

The angle between the crossing lines (64) and (65) is also important, for this design it is 90 degrees, although the desired size is from 60 to 120 degrees, the allowable is from 30 to 160 degrees.

The angle between the crossing lines (65) and (64) is also important, for this design it is 90 degrees, although the desired size is from 60 to 120 degrees, the allowable is from 30 to 160 degrees.

When the specified permissible angles are exceeded, the intensity of the vortex will be small in order to effectively wash out the granules from the grooves (52) of the portion roll (37).

Thus, the implementation of the granule feed unit (22) with an open channel (58) along and under the portion shaft (37) with such a flow area and such a shape and such an angle of entry of the main air flow that the main flow swirls when moving along the axis of the channel (58) , so that the streamlines of the vortex of the main flow enter the grooves of the shaft, which better affects the washing out of the granules from the grooves (52) of the portion shaft (37). Due to the vortex air flow, the granules are "washed out" from the grooves.

It should be noted that the granules usually have the geometry of elongated cylinders, and due to the elongated grooves (52) of the portion shaft (37), which are slightly larger than their length, the granules are more compactly placed in the grooves (52) and thereby increases the consumption of granules at the same rotation frequency, shaft diameter (37) and its working length.

Also, due to the vortex flow of compressed air and its high speed of compressed air, for example 46 m / s, the granules break, falling into its flow and moving under the lower seal (35) inside the housing (30), they begin to break, which leads to their smaller size and reduces the risk of clogging the narrow section in the cleaning nozzle (1). Due to the open channel (58) under the portioning roller (37), the granules have a place to fall out of the grooves (52).

Due to the constant open channel in any angular position of the portion shaft (37) and the absence of the need for flow through the grooves (52) of the portion shaft (37), the pressure loss is reduced, which affects the aggressiveness of cleaning.

Also, due to the flow entrance almost at a right angle, the flow swirls, which has a better effect on the "washing out" of the granules from the slots (52).

In this case, the lower entry (at an angle) into the groove can have either a curved surface for smoothing the flow or a sharp transition, this will not affect the vortex, since the flow of the medium itself will take the most convenient trajectory.

Claims (28)

1. A device for feeding granules of solid cryogenic substances into a stream of compressed air, containing a hopper for granules of solid cryogenic substances, connected to said hopper, a unit for feeding granules of solid cryogenic substances, made with the possibility of feeding granules of solid cryogenic substances from the hopper into a stream of compressed air, wherein said block of supply of granules of solid cryogenic substance contains a housing made with at least one compressed air inlet and outlet, bottom seal with grooves hermetically installed in the housing, a portioning shaft installed in the bottom seal and rotatable around an axis of rotation, wherein said portion shaft is provided with a peripheral surface in which a plurality of grooves are formed, and in the lower seal there is a through longitudinal channel made with the possibility of ensuring unobstructed flow of compressed air along the portion shaft from at least one inlet channel to the outlet channel with the provision of washing out granules of solid cryogenic substance from the slots of the portion shaft due to the vortex movement of compressed air, in this case, the through longitudinal channel is limited from the bottom by the body and from the sides by the lower seal, and from the top by the portion shaft, moreover, at least one inlet channel is made in such a way that its axis is located perpendicular to the axis of the through longitudinal channel of the lower seal and is offset relative to the axis of the through longitudinal channel along the vertical plane. 2. The device according to claim. 1, characterized in that at least one inlet and outlet channels are made in such a way that the axes of said channels are offset relative to each other in the horizontal plane. 3. The device according to claim. 1, characterized in that the housing of the granule feed unit is made with two inlet channels. 4. The device according to claim. 1, characterized in that at least one inlet channel and through longitudinal channels are made in such a way that they provide the movement of the compressed air flow with a double change in the direction of the flow, while the transition from channel to channel is made with radii of curvature. 5. The device according to claim 1, characterized in that at least one inlet and outlet channels, as well as a through longitudinal channel are made with a variable section and / or shape along the length of the channel. 6. The device according to claim 1, characterized in that grooves are made in the lower part of the lower seal, which are connected to at least one inlet channel. 7. The device according to claim. 1, characterized in that the lower seal is made with a continuous closed groove along its peripheral surface, in which the sealing ring is installed. 8. The device according to claim 1, characterized in that the unit for feeding granules of solid cryogenic substances additionally contains an upper seal installed on the lower seal and made with a surface contacting the peripheral surface of the portion shaft and provided with a lid, in which the means for mixing the granules are additionally installed solid cryogenic substances, performing reciprocating actions due to pneumatic cylinders. 9. The device according to claim. 1, characterized in that the portion shaft is made with two rows of circumferential grooves, with each circumferential row containing six slots. 10. The device according to claim. 1, characterized in that the grooves in the portion shaft are made along its circumference and are located along its axis, and are made in the form of a prism. 11. The device according to claim. 1, characterized in that the portion shaft is mounted on bearings, and the portion shaft is rotated due to the motor-reducer, with which the portion shaft is connected through an elastic coupling. 12. The device according to claim 11, characterized in that the bearings are installed in the walls of the housing of the unit for supplying granules of solid cryogenic substances, while a cover is made in one wall of the said housing to allow the portion shaft to be removed. 13. A method of feeding granules of a solid cryogenic substance into a compressed air stream using a device according to claim 1, including the steps at which feeding granules of solid cryogenic substance into the area above the portion shaft, ensuring that the granules of solid cryogenic substance enter the grooves of the portion shaft; carry out constant rotation of the portion shaft and move the granules of the solid cryogenic substance to the area under pressure; compressed air is fed into the granule feeding unit to ensure the movement of the compressed air flow with a double change in the direction of the flow, and a swirl of the compressed air flow is created, and the granules of solid cryogenic substance are washed out of the slots of the batch shaft with a vortex of compressed air at the same time, pressure is provided in the grooves of the lower seal with the creation of a hermetic seal of the batch shaft. 14. The method according to claim 13, characterized in that they provide movement of the compressed air flow along a horizontal straight line, then provide a sharp turn towards the vertical direction and carry out a sharp turn towards the horizontal direction. 15. The method according to claim. 14, characterized in that the flow turns by 90 degrees.

Images