Device for cleaning the internal surface of pipes
Patent Information
- Application Number
- PCT/RU2025/000049
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-02-26
- Publication Date
- 2026-09-03
Smart Images
Figure RU2025000049_03092026_PF_FP_ABST
Abstract
Description
[0001] DEVICE FOR CLEANING THE INTERNAL SURFACE OF PIPES
[0002] Field of technology to which the invention relates
[0003] The invention relates to the processing of rolled metal products, namely to devices for cleaning the inner surface of pipes and other long cylindrical products from contaminants, such as process lubricants, abrasives, sludge and other fine contaminants.
[0004] State of the art
[0005] A device is known [RU Patent No. 2115176, published July 10, 1998], comprising a cylindrical body with an internal working chamber and mounting pipes for the supply and discharge of liquid, a drive shaft located in the chamber with an activator mounted thereon. The activator is designed as a disk, on which movable cavitators are mounted normal to its side surfaces, overlapping the working chamber with a certain gap from its end walls. Fixed cavitators are mounted on the end walls of the working chamber.
[0006] The disadvantage is the insufficient quality and speed of cleaning the inner surface of cylindrical long products, low productivity of the cleaning process, the impossibility of use for pipes with a diameter greater than 50 mm, the inability to dry the inner surface of cylindrical long products after cleaning.
[0007] Disclosure of the essence of the invention
[0008] The technical problem solved by the invention is to develop a device for cleaning the inner surface of pipes, which creates intense surface cavitation inside the workpiece, thereby increasing the quality and speed of cleaning the inner surface of pipes, the efficiency and productivity of the cleaning process, expanding the range of processed pipes of small and medium diameters, for example, from 15 to 300 mm, and ensuring drying of the inner surface of the pipes after completion of the cleaning process.
[0009] The technical result consists in improving the quality and speed of cleaning the inner surface of pipes, increasing the efficiency and productivity of the cleaning process, and ensuring the drying of the inner surface of pipes after cleaning.
[0010] The technical result is achieved due to the fact that the device for cleaning the inner surface of pipes contains a cylindrical body with a working chamber, the base of which is made with through holes, a branch pipe for supplying a solution to the working chamber and an ejector connected to it by means of a hollow rod, wherein a fixed shaft is fixed at one end on which an activator is mounted, and at the other end of the shaft a disk with through holes or cutouts along the edges of the circle is fixed, while the activator is made in the form of a cylinder.
[0011] In addition, the activator is made in the form of a cylinder, which at the edges turns into a truncated cone.
[0012] In addition, the distance between the cylindrical surface of the activator and the inner surface of the pipe is in the range from 0.5 to 2 mm.
[0013] In addition, the through holes of the base of the working chamber are made slit-shaped in the form of half rings along the edges of the base of the working chamber.
[0014] In addition, the total area of the specified slotted openings in the form of half rings is equal to the cross-sectional area of the pipe supplying the solution to the working chamber.
[0015] Brief description of the drawings
[0016] Fig. 1 shows a diagram of the general appearance of a device for cleaning the inner surface of pipes in longitudinal section;
[0017] Fig. 2 shows a diagram of the general view of the device in longitudinal section, located inside the pipe;
[0018] Fig. 3 shows the placement of the device in the pipe in isometric view.
[0019] The following elements are indicated by numbers on the figures:
[0020] 1 - cylindrical body of the device; 2 - working chamber;
[0021] 3 - branch pipe;
[0022] 4 - hollow bar;
[0023] 5 - ejector;
[0024] 6 - base of the working chamber:
[0025] 7 - fixed shaft;
[0026] 8 - activator;
[0027] 9 - disk;
[0028] 10 - pipe.
[0029] Implementation of the invention
[0030] The proposed device includes a cylindrical body 1 having a working chamber 2, a branch pipe 3 for supplying a solution to the chamber, connected by means of a hollow rod 4 to an ejector 5, on the base 6 of the working chamber 2, made with through holes, a fixed shaft 7 is fixed at one end, on which an activator 8 is installed, made in the form of a cylinder turning into a truncated cone at the edges, and a disk 9 is fixed at the other end of the shaft.
[0031] The activator is shaped like a cylinder, which can be truncated at the edges, i.e., the edges of both end surfaces can be beveled toward the base and toward the disk, or only toward the base. The bevels toward the base can be positioned opposite the openings in the base of the working chamber and further direct the solution flow exiting the openings in the base toward the gap between the cylindrical surface of the activator and the inner surface of the pipe, ensuring a faster and more efficient cleaning process. Taking into account the deviation in the inner diameter of the pipe, the distance between the cylindrical surface of the activator and the inner surface of the pipe can range from 0.5 to 2 mm.This design of the activator further increases the intensity of surface cavitation, facilitating even more intensive cleaning of the pipe's inner surface from process lubricants and other contaminants. A distance greater than 2 mm between the cylindrical surface of the activator and the pipe's inner surface reduced the cavitation effect and overall cleaning quality. Distances less than 0.5 mm can make device advancement more difficult due to possible deviations in the pipe's inner diameter, preventing cleaning and ensuring the cavitation process necessary for high-quality cleaning.
[0032] The through-holes in the base 6 of the working chamber 2 can be slotted in the form of half rings along the edges of the chamber base (e.g., opposite the cylinder bevel). The total area of these slotted half-rings can be equal to the cross-sectional area of the nozzle. This design further improves the cavitation process and overall cleaning quality, further increases the solution flow rate, and makes the solution movement more directional, creating a more foamy mixture with more air bubbles.
[0033] The activator can be installed on a fixed shaft, with its end surface closely adjacent to the base of the working chamber or at some distance from it.
[0034] Disc 9 can be made with fluid-permeable holes (perforations) or cutouts along the edges of the circumference. The disc is necessary, among other things, for structural rigidity, while the cutouts facilitate the flow of fluid through the drain pipe.
[0035] The device works as follows.
[0036] The device is placed in pipe 10 (Fig. 2), then a pump unit (not shown) injects the working solution into the working chamber 2 through pipe 3 using a hollow rod 4 from the ejector 5. This creates a foamed mixture with air bubbles, which moves through through holes in the base 6 of the working chamber 2, which direct the solution's movement. As the solution pressure increases on the activator 8, the working solution moves forward toward the disk 9.Under these conditions, the gas or vapor bubbles present in the solution, moving with the liquid flow through the base of chamber 6, enter the activator 8 (in the gap between the inner surface of the pipe and the side surface of the activator) in the region of sharply increasing solution flow velocity and pressure less than critical according to Bernoulli's law, where they acquire the ability to grow indefinitely, then the growth stops and the bubbles begin to burst (collapse) with the formation of high-speed microjets of the solution and subsequent extrusion through the gaps between the inner surface of the pipe and the side surface of the activator 8. The contraction of the cavitation bubble occurs at high speed and is accompanied by a sound pulse.Under the influence of these factors, the required intensive surface cavitation is created and the inner surface of the pipe is cleaned with a gas-liquid mixture, the boundary oil layer and oil-fat contaminants are separated from the inner surface of the products, which ultimately ensures the effect of a high degree of cleaning of the inner surface of the pipe from process lubricants and other contaminants.
[0037] Thus, when using the proposed device, the intensification of cleaning processes and the effective removal of process lubricants increases due to the design features of the device and the physical and chemical processes that occur, which ensures an improvement in the quality of small and medium diameter pipes.
[0038] A device for cleaning the inner surface of pipes was manufactured and mounted in combination with a CR3-36F HQQE multistage pump (3.0 kW, 3*400V) on an experimental setup.
[0039] The proposed device was used to clean (remove Castrol TDN 86 process lubricant) the inner surface of cold-rolled stainless steel pipes made of 12X18N10T with a diameter of 16 mm, a wall thickness of 1 mm, and a length of 4 m with an initial contamination of 6050 mg / m2. The feed rate of the proposed device was 8 m / min. The distance between the cylindrical surface of the activator and the inner surface of the pipe was 2 mm. A working solution was continuously fed along the pipe surface to be cleaned, while compressed gas was simultaneously supplied to intensify the cleaning process. The working solution, with a temperature of 30-40°C, was supplied at a constant pressure of 10 atm. Water was used as the working solution, and compressed air at a pressure of 12 atm was used as the compressed gas.
[0040] During the pipe cleaning process, the proposed device is moved onto a permanently installed pipe. Once the activator is positioned in the pipe, the supply of the working solution is turned on. The device creates a surface cavitation effect with the activator of the proposed design. A powerful gas-liquid flow is pushed through the gaps between the activator and the pipe surface, and intensive cleaning of the inner surface occurs. PC17RU2025 / 000049 When the cleaning device returns to its original state, the supply of the solution is stopped and only compressed air is supplied, drying the pipe.
[0041] Similar tests were conducted for cleaning 30 mm diameter pipes with a 3.5 mm wall thickness and a length of 3 m, and 159 mm diameter pipes with a 2 mm wall thickness and a length of 4 m, with distances between the cylindrical surface of the activator and the inner surface of the pipe of 0.5 mm and 1.5 mm. For this purpose, the proposed devices were manufactured to match the internal diameters of the pipes.
[0042] Standard aqueous solutions containing surfactants and alkaline components (soda ash, sodium hydroxide, and others), as well as well-known degreasing solutions and aqueous solutions of detergents, such as LAVOMIX D103, used in production, can be used as degreasing solutions. Furthermore, this device provides high-quality cleaning of the internal surface of pipes in water.
[0043] Test results confirmed the high technical and technological performance of the cleaning device. The quality of cleaning the internal pipe surfaces from process lubricants was monitored based on the degree of contamination of a white cotton cloth. The quality of cleaning of the internal pipe surfaces was superior, with no residual contamination detected. Furthermore, the cleaning process using the proposed device was twice as fast as that of the prototype. The proposed device improves the quality of cleaning the internal surfaces of both small and medium diameter pipes. Furthermore, the proposed device allows for drying the pipe surface.
Claims
PC17RU2025 / 000049 CLAUSES OF THE INVENTION 1. A device for cleaning the inner surface of pipes, characterized in that it contains a cylindrical body with a working chamber, the base of which is made with through holes, a pipe for supplying a solution to the working chamber and an ejector connected to it by means of a hollow rod, wherein a fixed shaft is fixed at one end to the base of the working chamber, on which an activator is mounted, and a disk with through holes or cutouts is fixed to the other end of the shaft, wherein the activator is made in the form of a cylinder.
2. A device for cleaning the inner surface of pipes according to paragraph 1, characterized in that the activator is made in the form of a cylinder, which, along the edge of the end surface directed towards the base of the working chamber, is made to transition into a truncated cone.
3. A device for cleaning the inner surface of pipes according to paragraph 1, characterized in that the distance between the cylindrical surface of the activator and the inner surface of the pipe is in the range from 0.5 to 2 mm.
4. A device for cleaning the inner surface of pipes according to paragraph 1, characterized in that the through holes of the base of the working chamber are made slit-shaped in the form of half rings along the edges of the base of the chamber.
5. A device for cleaning the inner surface of pipes according to paragraph 4, characterized in that the total area of the said slotted openings in the form of half rings is equal to the cross-sectional area of the branch pipe supplying the solution to the working chamber.