Finishing device, finishing method and sealing system

Abstract

The present invention relates to a finishing device, a finishing method, and a sealing system. The sealing finishing device includes a thrust system, a plurality of sealing systems, each of which has a piston and a cylinder block that fits with the piston, and a plurality of conveying pipeline systems, each of which conveys the finishing medium contained in the corresponding sealing system to a different port of an internal flow path work for finishing, and the plurality of sealing systems communicate with each other through the internal flow path work. In this regard, the thrust system of the finishing device includes a vertical plunger pump connected to the piston to provide a driving force so that the piston can move vertically relative to the cylinder block, and the multi-stage pipeline includes a first stage pipeline and a second stage pipeline connected adjacent to the downstream of the first stage pipeline, the first stage pipeline has an elbow structure connected to the outlet end of the cylinder block, and the elbow structure is connected to the second stage pipeline extending horizontally.

Description

[Technical field]

[0001] The present invention relates to the field of precision machining of internal flow passages, and more particularly to a finishing apparatus, a finishing method and a sealing system. [Background technology]

[0002] Components having fine and complex internal flow passage structures are widely used in industrial fields such as aerospace, marine, nuclear, automotive, and mold industries. In particular, components related to fluid power systems often have complex internal cavity structures such as fine flow passages, small-diameter deep holes, and connections between fine flow passages and small-diameter deep holes, and perform functions such as transporting, exchanging, or applying hydraulic pressure to fluids, such as various engine fuel nozzles, heat exchangers, hydraulic modules, and oil passage control throttles in aviation / space / marine / automobile engines.

[0003] Process technologies that can fabricate fine and complex internal flow passages include precision machining, femtosecond / water jet guided / long pulse laser processing, spark processing, and additive manufacturing (3D printing), etc. Except for additive manufacturing technology, the fine and complex internal flow passage structures fabricated by other single processes are relatively simple and have a small length-to-diameter ratio, and need to be combined with other combination processes such as welding to fabricate fine and complex internal flow passages. The fine and complex internal flow passages produced by precision machining have problems such as burrs, sharp corners, and steps at the joints of the processed parts, the surface of the internal flow passage produced by femtosecond laser processing has the effect of attached residual particles and the surface "step", and the surface of the internal flow passage produced by water jet guided / long pulse laser and spark processing has the effect of remelting.Additive manufacturing (3D printing) is a technology that separates a complex 3D structure part model into a 2D structure and superimposes them layer by layer to form it, and it has become possible to form complex, fine and complex internal flow passage parts in one piece, so it is increasingly being applied in industrial fields such as aerospace, automobiles, and molds.However, additive manufacturing technology has its own process characteristics such as temperature gradient and layer by layer forming during the part forming process, so the surface of the internal flow passage of the part has the effect of semi-sintered or bonded powder particles and the surface "step".

[0004] Burrs during machining, particles sintered on internal flow paths during femtosecond laser processing, and adhesive powder on the surface of internal flow paths during additive manufacturing affect the performance and safety of parts. When burrs, attached residual particles, or adhesive powder fall off due to high-speed friction between the fluid flowing into the internal flow path and the surface, they become redundant and spread with the fluid, block the oil path, or cause mechanical wear failure, resulting in serious safety accidents. Inner surfaces with high roughness are prone to becoming the source of fatigue cracks during long-term use, and carbon accumulation is also likely to occur in high-temperature oil path systems. Traces of cutting edges on the surface of the flow path during machining, sharp corners or steps at the processing joints, and the "step" phenomenon on the surface of the internal flow path during femtosecond laser and additive manufacturing processing cause turbulence, vortexes, and a sudden increase in fluid friction resistance (Frictional Drag) in the fluid movement process, and further cause fluid runaway, generating vibrations and shortening the service life of parts. Rough surfaces can generate a large number of cavitation bubbles in the fluid, affecting combustion and hydraulic power, and can also cause cavitation corrosion. For internal flow paths and small connecting holes of parts made of specific materials such as hollow blades, fine cracks are likely to occur on the surface of the remelted layer, causing early failure of the parts, so it is necessary to reduce the thickness of the remelted layer or not allow the appearance of the remelted layer.

[0005] Therefore, when processing the internal flow passage surface of fluid power components by technologies such as precision machining, femtosecond / water jet guided / long pulse laser machining, spark machining, additive manufacturing (3D printing), etc., it will bring about adverse problems such as burrs, adhesive powder, sintered particle residues, rough surface, remelted layer, etc., and it is necessary to use appropriate surface finishing technologies to remove these adverse effects and meet the performance requirements of the product.

[0006] However, at present, the technology for effectively finishing the surfaces of fine and complex internal passages has not yet emerged, and as a result, the inner surface roughness of fine and complex internal passage workpieces made by additive manufacturing generally only has an original average roughness Ra after additive manufacturing of 6.3 μm or more, and there are no products with an optimum surface roughness Ra of 1.6 μm or less for internal passages, and no products with an optimum surface roughness Ra of 0.8 μm or less for fine and complex internal passage workpieces made by laser processing or spark processing have appeared. In addition, with regard to machined workpieces with fine and complex internal passages, there are no products with an optimum internal passage surface roughness Ra of 0.4 μm or less. However, currently, when fine and complex internal passages have complex, irregularly shaped passages such as S-shaped, L-shaped, U-shaped, or O-shaped bends, this cannot be achieved by machining, which only allows for linear feed, and can only be achieved by methods such as additive manufacturing. Therefore, at present, there are no products with an optimum internal passage surface roughness Ra of 1.6 μm or less produced by additive manufacturing. Summary of the Invention

[0007] It is an object of the present application to provide a finishing apparatus, a finishing method and a sealing system.

[0008] In a first aspect, the present application provides a finishing apparatus, the finishing apparatus comprising: a thrust system; a plurality of sealed systems, each of which has a piston and a cylinder block engaged with the piston to accommodate a finishing medium for finishing processing; the thrust system communicates with one end of the piston, and provides a driving force to the sealed systems to extrude the finishing medium from an outlet end of the cylinder block; and a plurality of conveying pipeline systems, each of which conveys the finishing medium accommodated in a corresponding sealed system to a different port of an internal flow path work for finishing, the plurality of sealed systems being communicated with each other via an internal flow path work, the upstream end of the conveying pipeline system being connected to an outlet end of the sealed system. a downstream end of the finishing device connected to the outlet end of the finishing device and a downstream end of the finishing device connected to the outlet end of the finishing device, the ratio of length to diameter of the conveying pipeline system being greater than 10:1, the diameter of the outlet end being greater than 3 mm, the conveying pipeline system having a multi-stage pipeline, and the ratio of cross-sectional areas of the front stage pipeline and the rear stage pipeline of two adjacent stages being greater than 1, wherein the thrust system of the finishing device has a vertical plunger pump connected to the piston for providing a driving force for moving the piston vertically relative to the cylinder block, the multi-stage pipeline having a first stage pipeline and a second stage pipeline connected adjacent to the downstream of the first stage pipeline, the first stage pipeline having an elbow structure connected to the outlet end of the cylinder block, the elbow structure being connected to the second stage pipeline extending horizontally.

[0009] In the technical proposal of the embodiment of the present application, the finishing device adopts a vertical structure consisting of a vertical plunger pump, a vertically moving piston, and a horizontal structure of the conveying pipeline, so that the synergistic effect of the two ensures the pressure stability during the finishing process of the finishing medium, and realizes a reliable finishing effect. Specifically, the vertical structure of the vertical plunger pump, piston, and cylinder block, and the horizontal conveying pipeline and workpiece correspondingly connected by an elbow structure, that is, the finishing device adopts a vertical and horizontal combination structure, so that the vertical plunger pump, piston, and cylinder block are not affected by the gravity rolling force, and the gravity effect can be cleverly utilized so that the pressure provided is very stable, and a larger operable table space can be provided for the finishing processing of the workpiece. In addition, the conveying pipeline adopts a structure in which the length-to-diameter ratio is greater than 10:1, the diameter of the outlet end is greater than 3 mm, and the cross-sectional area ratio of the front pipeline and the rear pipeline of the adjacent two pipelines of the multi-stage pipeline is greater than 1, so as to realize the transportation of the saturated flow rate of the conveyed finishing medium, and also ensure the pressure stability of the finishing medium in the conveying pipeline.

[0010] In some embodiments, the ratio of the cross-sectional area of ​​the first stage pipe to the cross-sectional area of ​​the second stage pipe is between 1.2 and 1.8.

[0011] In some embodiments, the multi-stage pipeline further includes a third stage pipeline connected adjacent to the downstream of the second stage pipeline, and a cross-sectional area ratio between the second stage pipeline and the third stage pipeline is 1.2 to 1.8.

[0012] In some embodiments, the apparatus further includes a tool having a port, and a ratio of a cross-sectional area of ​​the third stage pipeline to the port of the tool is 1.2 to 2.2. A ratio of a cross-sectional area of ​​the port of the tool to the port of the work internal flow path is 1.2 to 10.

[0013] In some embodiments, the piston has at least a first groove and a second groove from top to bottom, the sealing system further comprises a seal ring located between the piston and the cylinder block, the first seal ring being disposed in the first groove and the second seal ring being disposed in the second groove, and a radial gap between the piston and the cylinder block is between 1 mm and 2.5 mm.

[0014] In some embodiments, the first groove is a separate structure, the top surface of the piston is flat and a cover plate is removably provided thereon, the cover plate has a slope on its outer periphery, the slope forms a one-sided oblique groove with the top surface of the piston to form the first groove, the second groove is opened in a side wall of the piston, the first seal ring is made of a hard material, and the second seal ring is made of a soft material.

[0015] In some embodiments, the second groove comprises at least two grooves from top to bottom, including a first sub-groove and a second sub-groove, and a ratio of a depth of the second sub-groove to a depth of the first sub-groove is between 1.2 and 1.5.

[0016] In some embodiments, the angle of inclination of the one-sided oblique groove is greater than 60°.

[0017] In some embodiments, the material of the first seal ring satisfies a flexural modulus of 1.9 GPa to 3.6 GPa, an elongation of 60% to 120%, and a Knoop hardness of 90 Hk to 100 Hk, and the material of the second seal ring satisfies a flexural modulus of 0.2 GPa to 0.25 GPa, an elongation of 300% to 380%, and a flexural strength of 80 MPa to 100 MPa.

[0018] In some embodiments, the material of the first seal ring is one of pp, polytetrafluoroethylene, nylon, and peek, and the material of the second seal ring is one of silica gel, rubber, and nitrile.

[0019] In some embodiments, the cylinder wall of the cylinder block has a coating, the coating having a thickness of 50 μm to 220 μm and a hardness of 1500 HV to 2200 HV, and made of one or a combination of oxide, carbide, boride, and nitride ceramics.

[0020] In some embodiments, the coating has a surface roughness Ra of 0.05 μm to 0.4 μm, a circularity of 100 μm or less, and a cylindricity of 200 μm or less.

[0021] In some embodiments, the finishing device further comprises a diagnostic device, the diagnostic device having a flow rate and / or flow rate sensor and a pressure sensor for sensing the flow rate and / or flow rate and pressure of the finishing medium.

[0022] In some embodiments, the finishing medium comprises a liquid phase and a solid phase, the liquid phase has a viscosity of less than 1000 cP, the solid phase comprises abrasive grains, and the workpiece to be finished is a fine internal channel material having an aperture of 3 mm or less and a length to diameter ratio of 50:1 or more.

[0023] In a second aspect, the present application provides a finishing method using the finishing apparatus described in the first aspect, wherein the finishing medium has a liquid phase and a solid phase, the viscosity of the liquid phase is less than 1000 cP, the solid phase comprises abrasive grains, the workpiece to be finished is a fine internal flow passage material, the diameter of which is 3 mm or less and the length to diameter ratio is 50:1 or more, the thrust system of the finishing apparatus applies a predetermined pressure to the finishing medium so that the finishing medium flows through the fine internal flow passage at a flow velocity of greater than 5 m / s, and the flow rate of the finishing medium flowing into the interior of the fine internal flow passage from one end thereof reaches a saturation value of the flow rate that can be accommodated by the diameter of the fine internal flow passage so that the liquid pressure inside the internal flow passage is in a pressure-trapped state.

[0024] In a third aspect, the present application provides a sealing system, the sealing system comprising a piston, a cylinder block fitted with the piston, and a seal ring located between the piston and the cylinder block for containing a finishing medium for performing finishing processing, the piston being reciprocally movable along an extension direction of a cylinder wall of the cylinder block, a thrust system communicating with one end of the piston and providing a driving force to the piston, the piston having at least a first groove and a second groove extending from a top to a bottom, the sealing system being configured to couple the piston and the cylinder block to each other, The piston further includes a seal ring located between the piston and a cylinder block, the seal ring including a first seal ring provided in the first groove and a second seal ring provided in the second groove, the radial gap between the piston and the cylinder block is 1 mm to 2.5 mm, the first groove has a separate structure, the top surface of the piston is flat and a cover plate is removably provided thereon, the cover plate has a slope on its outer periphery, and the slope forms a one-sided oblique groove with the top surface of the piston to form the first groove, and the second groove is opened in a side wall of the piston. [Brief description of the drawings]

[0025] The above and other features, properties and advantages of the present invention will become more apparent from the following description in conjunction with the accompanying drawings and embodiments. It should be noted that the accompanying drawings are all illustrative and not drawn to scale, and should not be considered as limiting the scope of protection actually claimed by the present invention.

[0026] [Figure 1] 1 is a conceptual flow chart of a finishing method according to some embodiments of the present application; [Diagram 2] FIG. 1 is a schematic diagram of a finishing device according to some embodiments of the present application. [Diagram 3] Enlarged view of part A in Fig. 2 [Figure 4] Enlarged view of part B in Fig. 2 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Various embodiments or examples of the above-mentioned technical proposal are disclosed below. In order to simplify the disclosure, specific examples of each element and arrangement are described below, but these are merely examples and do not limit the scope of protection of the present invention. "An embodiment", "one embodiment", and / or "several embodiments" refer to features, structures, or special features related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "one embodiment" or "alternative embodiments" mentioned twice or more times in different positions in this specification do not necessarily refer to the same embodiment. Furthermore, some features, structures, or special features in expressions such as some embodiments, other embodiments, and further other embodiments of the present application may be appropriately combined.

[0028] In this application, flow charts are used to explain the operations performed by the system according to the embodiment of this application. It should be understood that the operations above or below are not necessarily performed in a precise order. Other operations can be added to these processes, or certain steps or operations can be removed from these processes.

[0029] Moreover, the average roughness described below refers to the case where multiple areas on the surface to be measured are selected and measured, the average value is taken, and the average roughness of the measured surface is obtained. The optimum roughness described below refers to the case where multiple areas on the surface to be measured are selected and measured, the minimum value is taken, and the optimum roughness of the measured surface is obtained. For example, when performing roughness measurement, an area for roughness measurement is a pipe segment having a length of 8 mm, and multiple pipe segments having a length of 8 mm are selected and measured in the pipe to be measured, and the minimum value is obtained.

[0030] Components with fine and complex internal flow passage structures are widely used in industrial fields such as aerospace, marine, nuclear, automotive, and molds. However, current machining processes, such as precision machining, femtosecond / waterjet guided / long pulse laser machining, spark machining, and additive manufacturing (3D printing), can result in adverse problems such as burrs, adhesive powder, sintered particle residues, rough surfaces, and remelted layers when processing the surfaces of internal flow passages in fluid power components. It is necessary to use appropriate surface finishing techniques to eliminate these adverse effects and meet the performance requirements of the products.

[0031] Currently, for fine internal flow passage workpieces made by additive manufacturing, there are no products with an optimum surface roughness Ra of 1.6 μm or less for the internal flow passage, and for fine internal flow passage workpieces made by laser processing or spark processing, there are no products with an optimum surface roughness Ra of 0.8 μm or less for the internal flow passage. In addition, for fine internal flow passage workpieces made by machining, there are no products with an optimum surface roughness Ra of 0.4 μm or less for the internal flow passage. However, if the fine internal flow passage has an irregular flow passage structure such as an S-shaped bend, L-shaped bend, U-shaped bend, or O-shaped bend, this cannot be realized by linear feed machining and can only be achieved by additive manufacturing, etc., so currently there are no products made by additive manufacturing with an optimum surface roughness Ra of 1.6 μm or less for the internal flow passage.

[0032] The inventors have conducted in-depth research and tried and compared various methods for finishing the surfaces of internal flow passages, and have discovered the following: When the internal flow passages of a part have a large diameter (>3mm), a small length-to-diameter ratio (<50:1), and extend in a substantially straight line, they can be finished by common methods such as manual polishing, chemical, electrochemical, plasma, magnetic force, magnetorheology, abrasive flow, water jet, and ultrasonic. However, when it comes to fine internal flow passages with small diameters (3mm or less) and large length-to-diameter ratios (50:1 or more), (1) Abrasive flow technology was adopted, and the inner cavity was finished by a pressing grinding mechanism using a semi-solid ointment finishing medium with high rigidity. However, the inventors discovered that this creep fluid with an extremely small Reynolds number is difficult to achieve uniform processing through a complex long-distance microchannel, and is prone to blockage at bends and dead corners, and that forcibly passing through it may cause the channel to deform or tear. Even if it barely passes through an internal channel with a length-to-diameter ratio of 50:1 or more, the pressure and flow rate will rapidly attenuate with the increase in fluid stroke, and the port of the internal channel will be "excessively grinded and polished", while the inside will be "unground and polished" due to excessive pressure and flow rate loss. In addition, the colloidal abrasive flow medium, which is insoluble in water, is prone to remaining in the curves and dead corners of the internal channel, and is difficult or impossible to completely remove after processing. (2) Abrasive water jet technology, also known as fine abrasive slurry jet, high-velocity flow, and high-velocity water particle finishing, is adopted. By applying liquid pressure to the water jet nozzle, a water jet containing abrasive particles is ejected from the nozzle, and the surface material of the workpiece is washed away by the impact kinetic energy. However, since the distance between the water jet nozzle and the part surface is short, the abrasive water jet technology is not effective on the fine internal flow passages with small internal flow passage diameters (less than 3 mm) and large length-to-diameter ratios (more than 50:1). (3) Although magnetic finishing technology was adopted, it can only perform a slight polishing process on the surface of an internal flow passage that is larger than 3 mm in diameter and extends in an approximately linear manner, and cannot perform an effective surface finishing process on a fine and complex internal flow passage that is 3 mm or less in diameter and extends in three dimensions, such as S-shaped bends, L-shaped bends, U-shaped bends, O-shaped bends, and spiral bends. The reasons are as follows. Magnetic finishing is a flexible process that uses relatively large magnetic needle abrasive grains and is based on the principle that surface convex and concave points are simultaneously processed under the action of an applied magnetic field. Therefore, these flexible processing means can only perform a slight polishing improvement on the surface, and even if a large amount of material is removed, it cannot significantly improve the "step" effect on the surface, reduce the surface roughness, significantly peel off the powder and particles attached to the surface, and improve burrs. In addition, since this method is restricted by the movement of the magnetic field, it cannot be used to finish complex internal flow passages that extend in three dimensions in parts. (4) Although a chemical finishing method was adopted, the small diameter of the internal flow passages meant that only a small amount of corrosive solution could be accommodated, making the efficiency of the chemical finishing method extremely low, and even making finishing impossible due to localized accumulation of reactive bubbles. (5) Electrochemical, plasma finishing and ultrasonic methods have been adopted, but they are unable to finish the fine and complex internal flow paths because it is difficult to place tracing electrodes inside the flow paths which are narrow and extend three-dimensionally and include S-shaped bends, L-shaped bends, U-shaped bends, O-shaped bends, spiral bends, etc. In addition, for (4) and (5), chemical, electrochemical, plasma finishing methods can cause various corrosion and layer defects on the microstructure of the flow path substrate, and the corrosive liquid and reactive gas also have adverse effects on the environment and equipment. At the same time, (4) and (5) are also flexible processing methods, and have the same disadvantages as (3), which can only make a slight polishing improvement to the surface, and even if the amount of material removed is large, the "step" effect on the surface cannot be significantly improved, the surface roughness can be reduced, and the powder, particles and burrs attached to the surface cannot be significantly removed.

[0033] Based on the above, the inventors have conducted intensive research and discovered that the above-mentioned processing methods are difficult to apply to finishing processing of fine internal flow paths because they all face problems such as difficulty in finishing deep parts of fine internal flow paths and / or the finishing quality is not ideal when it comes to the structure of fine internal flow paths.

[0034] Based on the above, the inventors have further researched and invented a surface finishing method for fine internal flow passages, which uses a two-phase flow finishing medium with a viscosity of less than 1000cP, makes the flow rate of the two-phase flow finishing medium in the fine internal flow passage greater than 5m / s, and makes the flow rate flowing into one end of the fine internal flow passage reach the saturation value of the flow rate that can be accommodated by the diameter of the fine internal flow passage, so that the liquid pressure inside the internal flow passage is in a pressure-filled state, thereby forming a means for the liquid to reach the saturation flow rate for the fine internal flow passage, that is, the synergistic action of the low-viscosity liquid phase, the fluid flow rate of the finishing medium, and the saturation flow rate solves the difficult problem of finishing the fine internal flow passage. The principle is described below. First, the synergistic action of the three factors, low viscosity liquid phase, fluid flow rate and saturation flow rate, allows the finishing medium to smoothly enter the fine and complex internal flow passage and form a state similar to a non-Newtonian fluid in the fine and complex internal flow passage, the fluid boundary layer is parallel to the surface of the internal flow passage, and the abrasive grains in the hard non-Newtonian fluid "like a blade" realize target processing of the surface convex points by shear friction. In addition, the synergistic action of the above three factors provides a micro-cutting force due to friction between the abrasive grains in the finishing medium and the surface of the fine and complex internal flow passage, so that the surface optimum roughness can be matched with the range of the average contact length of the abrasive grain cutting edge without being limited by the material of the fine and complex internal flow passage, and even a super-mirror quality with an optimum surface roughness Ra of 0.05 μm can be achieved, breaking through the limitations of the principles of abrasive flow and water jet technology. The principle is described below. Since the cutting mechanism of abrasive flow technology is based on the volume force generated by the pressing of the abrasive grains against the surface, when processing low-hardness metals and polymer flexible materials, dents and pits are likely to occur (Ra>0.8 μm). The cutting force in abrasive waterjet technology is the erosive force caused by the impact of abrasive grains on the surface, and when machining soft metals, the surface is prone to roughening (Ra>0.8μm).

[0035] In order to develop a finishing device corresponding to the above surface finishing method, the inventors discovered that in order to ensure sufficient speed for the finishing medium to realize the shear friction caused by the "knife-like" hard fluid and target processing of surface convex points, the finishing device needs to provide a large pressure to the finishing medium; and, under high pressure conditions, in order to avoid the polishing runaway of the finishing medium and obtain an ideal finishing effect, there are high requirements for pressure precision and fluctuation range; and, the inventors discovered that due to the strong abrasive effect of the high-pressure two-phase flow finishing medium on the sealed system, the seal of the finishing system and the corresponding life of the sealed system are also problems that need to be solved.

[0036] Based on the above, the inventors have studied deeply and designed a vertical and horizontal combined device structure. Specifically, a horizontal conveying pipeline system is adopted together with a vertical thrust system and a sealing system, and a vertical structure of a vertical plunger pump, a vertical piston moving piston, and a horizontal conveying pipeline are adopted in the finishing device, so that the synergistic effect of the two can ensure the pressure stability during the finishing process of the finishing medium, and achieve a reliable finishing effect. Specifically, the vertical plunger pump, piston, and vertical structure of the cylinder block, and the horizontal conveying pipeline and workpiece correspondingly connected by an elbow structure, that is, the vertical and horizontal combined structure in the finishing device can be used to effectively make the vertical plunger pump, piston, and cylinder block not affected by the gravity rolling force, and the gravity effect can be skillfully utilized so that the pressure provided is very stable, and a larger operable table space can be provided for the finishing processing of the workpiece. In addition, the conveying pipeline has a length-to-diameter ratio of greater than 10:1, an outlet end bore of greater than 3 mm, and a cross-sectional area ratio of the front-stage pipeline to the rear-stage pipeline of two adjacent pipelines of the multi-stage pipeline is greater than 1, thereby realizing the conveying of a saturated flow rate of the conveyed finishing medium and ensuring the pressure stability of the finishing medium in the conveying pipeline. In addition, the synergistic effect of the multiple grooves and corresponding multiple seal rings in the sealed system and the means for a gap of 1 mm to 2.5 mm between the piston and the cylinder block allows the sealed system to seal the finishing medium well, and the piston can be smoothly advanced when advancing the finishing medium, thereby achieving a balance between sealing performance, advancing performance, and sealed system life.

[0037] It can be understood that the surface finishing device of the internal flow passage disclosed in the embodiment of the present application can provide a stable and large pressure, which can help solve the problem of the inability to finish the surface of the fine internal flow passage with a small diameter (less than 3 mm) and a large length-to-diameter ratio (more than 50:1), thereby obtaining a fine internal flow passage workpiece with an inner surface optimum surface roughness Ra of 1.6 μm or less, and the workpiece may have a fine and complex internal flow passage workpiece that is three-dimensionally stretched and includes S-shaped bending, L-shaped bending, U-shaped bending, O-shaped bending, and spiral bending, such as a fuel nozzle, heat exchanger, hydraulic unit, and oil passage control throttle of various engines in aviation / space / shipping / automobiles. It can also be understood that the disclosed in the embodiment of the present application can be applied not only to the surface finishing method introduced, but also to other fluid processing methods that require stable and large pressure.

[0038] It is necessary to explain that the terms "diameter" and "length" in the context mean equivalent diameter and equivalent length, and the ratio of length to diameter is the ratio of equivalent length to equivalent diameter. Regarding the equivalent diameter, the cross-sectional shape of the internal flow passage may be a circle, an ellipse, etc., whose cross-sectional outline is composed of a closed curve (non-broken line). The cross-sectional shape of the internal flow passage may be a rectangle, a triangle, etc., whose cross-sectional outline is composed of a closed broken line. Since the cross-sectional outline is composed of any closed curve (non-broken line) or a closed broken line, and the cross-sectional outline is an irregular shape, the equivalent diameter is introduced and the equivalent diameter is defined as follows: For any cross-sectional shape, an ideal circle is taken that is equal to the actual cross-sectional area of ​​the any cross-sectional shape, and the diameter of this ideal circle is the equivalent diameter. The equivalent length refers to the entire path that the fluid in the internal flow passage actually flows between two ports of the internal flow passage.

[0039] First, in order to understand the effect of the finishing device of the present application, a surface finishing method for fine internal flow passages to which the finishing device can be applied will be introduced.

[0040] Referring to FIG. 1 , the present application provides a method for finishing a surface of an internal flow passage, the method comprising: Using a liquid-solid two-phase flow finishing medium, the liquid phase of which has a viscosity of less than 1000 cP and the solid phase of which is an abrasive; A predetermined pressure is applied to the finishing medium so that the finishing medium flows through the fine internal flow passage at a flow velocity of greater than 5 m / s, the flow rate of the finishing medium flowing into the fine internal flow passage from one end thereof reaches a saturation value of the flow rate that can be accommodated by the diameter of the fine internal flow passage, and the liquid pressure inside the internal flow passage is in a pressure-trapping state.

[0041] The liquid here has a viscosity of less than 1000 cP, and all descriptions of viscosity values ​​in this application refer to the Ubbelohde viscosity at room temperature (around 25°C). The optimum value of the viscosity of the liquid phase corresponding to the finishing method corresponding to the fine internal flow passages with different materials, dimensions, and initial average roughness can be obtained by constantly increasing the viscosity based on the lower limit. Currently, the lower limit of the viscosity in the embodiment is about 50 cP, and the inventors have found through a large amount of test data that for the fine internal flow passages of common materials such as titanium alloys, high temperature alloys, steel, ceramics, aluminum alloys, and polymer materials, the viscosity of the liquid phase needs to be at least 50 cP to reach the target roughness value after finishing. The critical value of 1000 cP here is not generally the optimum value, but the limit value at which the finishing medium flows continuously, smoothly, and stably through the fine internal flow passages.

[0042] The liquid phase described in the examples is, for example, an aqueous liquid phase, in which a certain thickener is added to deionized water so that the aqueous liquid has a certain viscosity. The beneficial effects of using an aqueous liquid are that it is low-cost, easy to obtain, environmentally friendly, and the finishing medium is easy to wash after finishing is completed. However, it is understood that the liquid phase here is not limited to an aqueous liquid as long as it is a liquid with a viscosity μ of less than 1000 cP.

[0043] The material of the solid phase abrasive grains may be a common abrasive material, such as carbide ceramics including silicon carbide, tungsten carbide, etc., oxide ceramics including aluminum oxide, zirconium oxide, cerium oxide, etc., nitride ceramics including boron nitride, chromium nitride, etc., and natural minerals including diamond / sand, mica, quartz, olivine, etc. Preferably, the material may be one or more combinations of diamond / sand and oxide ceramics.

[0044] When selecting the particle size and mass concentration of the abrasive grains, it is common to gradually increase them based on the lower limit value to obtain the optimal value range. If the particle size and mass concentration of the abrasive grains are below the lower limit value, the expected finishing effect cannot be achieved, that is, the fine internal flow passage cannot achieve the target value of surface roughness. The principle is that if the particle size is too small, the mass of the abrasive grains themselves is too low to generate enough kinetic energy to achieve effective abrasive grinding, and if the mass concentration is too small, the grinding probability of the surface processing point is reduced and effective abrasive grinding cannot be achieved. The selection of the lower limit value is generally conservative, for example, any lower limit value can be conservatively selected on the premise that it does not exceed the upper limit value of the particle size, and the lower limit of the ratio of the internal flow passage diameter to the particle size of the abrasive grains is usually 20, that is, the internal flow passage diameter must ensure that at least 20 abrasive grains are not clogged when passing through in parallel, that is, the upper limit of the particle size of the abrasive grains is usually 1 / 20 of the internal flow passage diameter, and the lower limit of the abrasive grains is generally 1 / 5 of the upper limit value. The lower limit of the mass concentration of the abrasive grains is generally 10g / L, and the selection of the lower limit is generally relatively conservative, because the pressure of the system is relatively large, and clogging of the abrasive grains may cause the scrapping of the workpiece and the system, or may cause cracking and explosion. Therefore, the grain size and mass concentration of the abrasive grains are gradually increased according to the predetermined lower limit, until the grain size and mass concentration of the abrasive grains are too large and the grain size and mass concentration are too high, which causes significant flow resistance and reduces the flow rate, and the mutual collision between the abrasive grains affects the flow rate and reduces the flow rate and grinding effect, that is, the optimum value can be obtained by testing according to the lower limit.

[0045] A predetermined pressure is applied to the finishing medium so that the finishing medium flows through the fine internal flow passage at a flow rate of more than 5 m / s. The predetermined pressure here means a pressure that allows the finishing medium to flow through the fine internal flow passage at a flow rate of more than 5 m / s even in the initial state of the finishing process, and as the finishing progresses, the internal flow passage surface roughness decreases, and under the same pressure conditions, the flow rate of the finishing medium in the fine internal flow passage becomes faster and faster. It can be understood that the realized flow rate is in a certain range, so the predetermined pressure here is a concept of a range, and not that only a specific value can be applied to the finishing medium. To measure the flow rate of the finishing medium inside the fine internal flow passage, immersion measurement cannot be adopted, otherwise the abrasive grains may damage the sensor probe. The method of ultrasonic velocity measurement can be adopted, and indirect measurement can also be performed using the Hagen-Poiseuille law of viscous fluid (see below). In the formula, D is the internal passage diameter, l is the length of the fine internal passage, p is the pressure difference acting on both ends of the fine internal passage, i.e., the hydraulic pressure p, Re is the Reynolds number, um is the liquid phase flow velocity in the aqueous two-phase flow, ρl is the density of the liquid phase, and the liquid phase flow velocity is approximately equal to the flow velocity of the completion medium.

number

[0046] The flow rate of the finishing medium is greater than 5m / s, based on the theoretical critical conditions for forming non-Newtonian fluid and the critical value obtained by the inventors through long-term practice. According to engineering fluid dynamics data (e.g., book data: Yang Shuren, Wang Zhiming, He Guangyu, etc., Engineering Fluid Dynamics [M]. Petroleum Industry Press, 2006), the viscosity of pure water is 1cP, and the critical motion flow rate of non-Newtonian fluid is greater than 16.6m / s, but the lower limit of the viscosity of the liquid phase in this embodiment is 50cP, which is greater than 1cP, so the critical flow rate of non-Newtonian fluid is less than 16.6m / s. At the same time, combining the results of practice, the inventors found that ideal processing effect cannot be obtained below 5m / s, so the critical value is 5m / s.

[0047] The flow rate at which the finishing medium flows into one end of the fine internal flow passage reaches a saturation value of the flow rate that can be accommodated by the diameter of the fine internal flow passage, and the liquid pressure inside the internal flow passage becomes high, that is, the so-called saturated flow rate state in this field.

[0048] The saturation value of the capacity flow rate and the state of saturation flow rate herein refer to the state in which the fluid fills the cross section of the pipe when it flows into the pipe, and the cross section of the pipe can accommodate the maximum number of fluid molecules in parallel.

[0049] It can be seen that the beneficial effects of the finishing method of the above embodiment are as follows:

[0050] The viscosity of the liquid phase of the finishing medium is less than 1000cP, the flow rate of the two-phase finishing medium in the fine internal passage is greater than 5m / s, the flow rate flowing into one end of the fine internal passage reaches the saturation value of the flow rate that can be accommodated by the diameter of the fine internal passage, the liquid pressure inside the internal passage is in a pressure-filled state, and a means is formed for the liquid to reach the saturation flow rate for the fine internal passage, that is, the synergistic effect of the low viscosity liquid phase, the fluid flow rate, and the saturation flow rate solves the difficult problem of finishing the fine internal passage. The principle is described below. First, due to the synergistic effect of the three factors of low viscosity liquid phase, fluid flow rate and saturation flow rate, the finishing medium is in a state of low viscosity and high flow rate, so it can smoothly enter the fine internal flow passage and form a non-Newtonian fluid in the fine internal flow passage, the fluid boundary layer is parallel to the surface of the internal flow passage, and the abrasive grains in the "blade-like" hard liquid phase realize target processing of the surface convex points by shear friction, and in principle overcome the problem that the surface convex points and concave points are processed simultaneously during flexible processing, which can only be slightly polished. At the same time, due to the micro-cutting force caused by the friction between the abrasive grains of the finishing medium and the surface of the fine internal flow passage, it is possible to obtain an optimal surface roughness that matches the average contact length range of the abrasive grain cutting edge without being limited by the material of the fine internal flow passage, and break through the limitations of the principles of abrasive flow and water jet technology. The principle is described below. Since the cutting mechanism of abrasive flow technology is based on the volume force generated by the pressing of the abrasive grains against the surface, when processing metals and polymer flexible materials with low hardness, dents and pits are likely to occur (Ra>0.8μm). The cutting force in abrasive waterjet technology is the erosion force caused by the impact of abrasive grains on the surface, and when processing soft metals, the surface is easily roughened (Ra>0.8μm). In addition, in the low viscosity and high flow rate fluid dynamics conformal processing method, the steps, sharp corners, geometric contour curvatures, and other locations that do not conform to fluid engineering on the internal flow channel surface are polished more, and the corners, sharp edges, internal flow channel contour curvatures, and hole shapes are geometrically streamlined, further improving the fluid movement performance of the internal flow channel. In addition, the above example proposed that the critical flow velocity is 5m / s to realize a blade-like hard non-Newtonian fluid using the flow rate of the finishing medium and to realize target processing of surface convex points by the shear friction of the abrasive grains.

[0051] Regarding the machining time of the finishing medium in the fine internal flow passage, the finishing medium may finish the fine internal flow passage during a reference period until the surface optimum roughness of the fine internal flow passage reaches a target value. The reference period here may be a predetermined continuous period, or may be a plurality of intermittent periods, or the finishing process may be automatically stopped after detecting that the flow rate of the finishing medium reaches a flow rate corresponding to when the surface optimum roughness of the fine internal flow passage is a target value after a non-predetermined continuous period after starting. For example, as described above, in some embodiments, after starting machining, the flow rate or flow rate of the finishing medium in the fine internal flow passage is measured to indirectly obtain the surface optimum roughness in a characteristic representation, and when the flow rate or flow rate value reaches a predetermined value, the corresponding surface optimum roughness reaches the target value, so that the finishing process is stopped manually or automatically at this time. The meaning of the surface optimum roughness being a target value here does not necessarily mean that the surface optimum roughness does not necessarily need to be measured directly, but may be indirectly characterized, for example, as introduced above, it may be a method of characterizing the flow rate, flow rate, etc. of the finishing medium inside the fine internal flow passage. The above target values ​​refer to the set optimum surface roughness values, and generally refer to the requirements for the final optimum surface roughness of the fine internal flow passages, but it is not excluded that further finishing may be carried out after the above finishing steps, and what is set at this time is not the requirement for the final optimum surface roughness.

[0052] In summary, the finishing method introduced in the above examples solves the long-standing industry challenge of finishing fine internal passages with a diameter of 3 mm or less and a length-to-diameter ratio of 50:1 or more by combining measures such as constructing a hydraulic system at both ends of the internal passage to be processed, utilizing a low-viscosity, high-speed solid-liquid two-phase fluid, reaching a saturation flow rate of the internal passage to be processed, and a fine cutting mechanism generated by the abrasive grains in the two-phase flow rubbing against the internal passage surface at high speed.

[0053] Referring to FIGS. 2-4, in some embodiments, the present invention provides a finishing apparatus 100 comprising a thrust system 101, a number of containment systems 102, and a number of conveying pipeline systems 103. In some embodiments, the finishing apparatus 100 comprises a thrust system 101, a number of containment systems 102, and a number of conveying pipeline systems 103.

[0054] Each sealed system 102 has a piston 21 and a cylinder block 18 that fits with the piston 21 to contain the finishing medium 8 for finishing, and the thrust system 101 communicates with one end of the piston 21 and provides a driving force to the piston 21 to push the finishing medium 8 out of the outlet end 190 of the cylinder block 18.

[0055] Each conveying pipeline system 103 conveys the finishing medium 8 contained in the corresponding sealing system 102 to a different port of the internal flow path work 34 for finishing, for example, one set of the sealing system 102 and the conveying pipeline system 103 shown in FIG. 2 corresponds to the inlet of the work 34, and another set corresponds to the outlet, so that the multiple sealing systems communicate with each other through the work 34. The upstream end of the conveying pipeline system 103 is connected to the outlet end 190 of the sealing system 102, and the downstream end discharges the finishing medium 8 to the internal flow path work 34 for finishing, the ratio of the length to the diameter of the conveying pipeline system 103 is greater than 10:1, the diameter of the outlet end is greater than 3 mm, and the conveying pipeline system 103 has multiple pipelines, and the ratio of the cross-sectional area of ​​the front pipeline to the rear pipeline of the two adjacent pipelines is greater than 1.

[0056] The thrust system 101 includes a vertical plunger pump 5 connected to a piston 21 to provide a driving force for moving the piston 21 vertically relative to a cylinder block 18, and a multi-stage pipeline includes a first stage pipeline 22 and a second stage pipeline 23 connected adjacent to the downstream of the first stage pipeline, the first stage pipeline having an elbow structure connected to an outlet end 190 of the cylinder block 18, and the elbow structure is connected to the second stage pipeline 23 extending horizontally, thereby realizing a combination of a vertical structure and a horizontal structure.

[0057] The thrust system 101 may be a hydraulic system, and as shown in FIG. 2, includes a motor 1, a hydraulic tank 2, a hydraulic pump 3, a booster device 6, a vertical plunger pump 5 and an oil pipe 4. The motor 1 drives the hydraulic pump 2 to extract hydraulic oil at a certain pressure from the oil tank 2, and the pressure oil boosted by the booster device 6 is delivered to the vertical plunger pump 5. The vertical plunger pump 5 is connected to the piston 21 through the ball head 13 and drives the piston 21 to discharge the finishing medium 8 from the discharge end 190 of the cylinder block 18. The motor-driven hydraulic system not only has a large thrust, but also has high thrust precision.

[0058] Corresponding to the configuration of the vertical plunger pump 5, the sealed system 102 must also be of a vertical configuration in which the movement direction of the piston 21 relative to the cylinder block 18 moves along the vertical direction, but the corresponding machined workpiece 34 must be of a horizontal type, so that the change in direction can be completed by the conveying pipeline system.

[0059] The beneficial effect of adopting the above embodiment is that the finishing device adopts a vertical structure consisting of a vertical plunger pump, a vertically moving piston, and a horizontal structure of a conveying pipe, and the synergistic effect of the two ensures the pressure stability during the finishing process of the finishing medium, thereby realizing a reliable finishing effect. Specifically, by adopting the vertical structure of the vertical plunger pump, piston, and cylinder block, and the horizontal conveying pipe and workpiece correspondingly connected by an elbow structure, that is, by adopting a vertical and horizontal combined structure in the finishing device, the vertical plunger pump, piston, and cylinder block are not affected by the gravity rolling force, and the gravity effect can be skillfully utilized so that the provided pressure is very stable, and a larger operable table space can be provided for the finishing processing of the workpiece. In addition, the conveying pipeline has a length-to-diameter ratio greater than 10:1, an outlet end diameter greater than 3 mm, and a cross-sectional area ratio between the front-stage pipeline and the rear-stage pipeline of two adjacent pipelines of the multi-stage pipeline is greater than 1, thereby realizing the transportation of the saturated flow rate of the transported finishing medium and ensuring the pressure stability of the finishing medium in the conveying pipeline.

[0060] A plurality of sealed systems 102 are connected to the workpiece 34, i.e., the plurality of sealed systems 102 are connected to each other via the workpiece 34 to realize fluid exchange, i.e., one sealed system 102 discharges the finishing medium 8 to the workpiece 34, and another sealed system 102 receives the finishing medium 8 flowing out from the workpiece 34. When the finishing medium 8 of one sealed system 102 is all consumed, the other sealed system 102 can continue finishing processing on the workpiece 34 in the opposite direction to the previous direction through the received finishing medium 8, i.e., the other sealed system 102 discharges the finishing medium 8 to the workpiece 34 at this time, and the sealed system 102 that has all consumed the finishing medium receives the finishing medium 8 flowing out from the workpiece 34 at this time, so that the finishing medium 8 contained in at least one sealed system 102 can always be provided to the workpiece 34, thereby ensuring continuous finishing work of the workpiece 34 and making the finishing process efficient.

[0061] As shown in FIG. 2, the finishing apparatus 100 may further include an operation module having a touch operation display 10, a switch 9 for turning the apparatus on / off, an emergency stop switch 11 for forcibly turning off the apparatus, and an operation table 12 for connecting an external processing operation module.

[0062] The number of sealed systems 102 and conveying pipeline systems 103 is shown as two in the figure as an example, but is not limited to this, and the number of thrust systems 101 may be such that each sealed system 102 shown in the figure corresponds to one thrust system 101.

[0063] The cylinder block 18 defines a space through a bottom plate and a top plate 19, which are connected to the cylinder block 18 through a bolt 7, the space between the piston 21 and the top plate 19 accommodates the finishing medium 8, and the opening of the top plate 19 is the outlet end 190 of the sealing system 102. The diameter ratio of the cylinder block 18 to the outlet end 190 is 10-32 to further boost the finishing medium. As shown in FIG. 4, in some embodiments, the cross-sectional area ratio of the first stage pipe 22 to the second stage pipe 23 may be 1.2-1.8, which can steadily and gradually boost the finishing medium and keep the saturation flow rate. In some embodiments, the multi-stage pipeline further includes a third stage pipeline 32 connected adjacent to the downstream of the second stage pipeline 22, and the cross-sectional area ratio of the second stage pipeline 22 to the third stage pipeline 32 is 1.2 to 1.8, and the length of the third stage pipeline 32 may be short, as shown in the figure, in the same manner as the joint form. By adopting a three-stage pipeline and a structure with a cross-sectional area ratio per stage of 1.2 to 1.8, it is possible to steadily and gradually increase the pressure while maintaining a saturated flow rate, and not only ensure the condition of providing a stable pressure to the finishing medium, but also ensure the strength reliability and service life of the conveying pipeline system 103.

[0064] Referring to FIG. 4, in some embodiments, the finishing device may further include a tool 31, which has at least two ports 310 corresponding to at least one inlet and at least one outlet of the workpiece 34. The tool 31 is stably fixed via a three-axis clamp 33 on the table, and the workpiece 34 is clamped inside the tool 31 by a clamp bolt 30 of the tool. The ratio of the bore of the third conduit 32 to the cross-sectional area of ​​the port of the tool 31 connected thereto may be 1.2 to 2.2, and the beneficial effect of this is similar to that described above, and the pressure can be steadily and gradually increased while the saturated flow rate can be maintained. Note that the upper limit of the cross-sectional area ratio of the third conduit 32 to the port of the tool 31 connected thereto may be 2.2, which is higher than the upper limit of the cross-sectional area ratio between the conduits, which is 1.8. This is because the tool 31 is generally replaced frequently and the requirements for its service life are not as strict as those of the conduits, so the upper limit of the cross-sectional area ratio can be set to be larger. In some embodiments, the ratio of the cross-sectional area of ​​the tool port to the workpiece 34 port should be greater than 1 and less than 10. Both may be sealed with epoxy resin. If the ratio is greater than 1, the internal flow path of the workpiece can be saturated, but if the ratio is too large, the inventors found that the relief pressure for the workpiece 34 port is too large, which increases the strength and sealing requirements of the connection between the port and the workpiece, and even leads to safety accidents such as the breakage of the connection, so the inventors found that the ratio should be less than 10. It can be understood that the tool 31 may be provided with many spare ports 310 suitable for internal flow paths of workpieces with different calibers. When one of the ports is used, the other unused ports can be connected and blocked by bolts. The clamp bolts 30 of the tool 31 include an upper clamp bolt and a tool lower clamp bolt, which can clamp the workpieces 34 with different standard dimensions, and adjust the tool port and the workpiece internal flow path port to the same axis as the tool port and the multi-stage pipeline port.

[0065] The inventors have discovered that by adopting the multi-stage conveying pipeline system introduced in the above embodiments, a thrust system configuration combining a hydraulic pump and a vertical plunger pump, and a combined vertical and horizontal structure, it is possible to achieve high precision (with an error of 0.01 MPa) even when providing a thrust of 50 MPa or more, and the pressure fluctuation during operation is small and falls within ±0.1%, making it possible to very effectively realize the above-mentioned finishing method.

[0066] As shown in Figures 2 and 3, for the sealing system 102, the inventors have discovered that since it is necessary to provide a large pressure to the finishing medium, the issue of sealing between the piston 21 and the wall of the cylinder block 18 is particularly important, and it is necessary to ensure the sealing while also ensuring the smooth movement of the piston 21 along the inner wall of the cylinder block 18.

[0067] The piston 21 has at least a first groove 211 and a second groove 210 from the top to the bottom, and the sealing system 102 further includes a seal ring located between the piston 21 and the cylinder block 18, the seal ring including a first seal ring 17 provided in the first groove 211 and a second seal ring 170 provided in the second groove 210, and the radial gap between the piston 21 and the cylinder block 18 is 1mm to 2.5mm. By adopting the structure of the multi-stage grooves and multi-stage seal rings, and the gap between the piston and the cylinder block is 1mm to 2.5mm, the first stage seal ring can filter the abrasive grains of the two-phase flow, and the second stage seal ring seals the pure liquid phase, such as the aqueous liquid phase, thereby realizing good sealing performance against the finishing medium. The inventors have found that in the gap range of 1mm to 2.5mm, a good sealing effect can be maintained and the piston can be ensured to move smoothly along the wall surface of the cylinder block 18 to push out the finishing medium 18.

[0068] 3, the first groove 211 of the piston 21 is a separate structure, the top surface 212 of the body of the piston 21 is flat, and the cover plate 20 is removably provided thereon, the cover plate 20 has a slope 201 on the outer periphery, the slope 201 forms a one-sided oblique groove with the top surface of the piston 21 to form the first groove 211, the second groove 210 is opened on the side wall of the piston, the material of the first seal ring 17 is a hard polymer material, and the material of the second seal ring 170 is a soft polymer material. The principle is described below. The inventors found that due to the large pressure, no matter how the first seal ring seals, the abrasive grains will fit into the gap between the cylinder wall and the seal ring and scratch the seal ring, so the one-sided oblique groove and hard seal ring structure are provided to guide the abrasive grains to actively fit / slide into the first seal ring 17, forming a fitting-type self-sealing structure, and therefore the first seal ring 17 is made of a hard polymer material. On the other hand, after most of the abrasive grains are actively fitted into the first seal ring 17, the material that needs to be sealed by the second seal ring 170 becomes the liquid phase in the two-phase flow, so it is sealed using the soft second seal ring 170. The reason why the first groove 211 needs to be a separate structure is that the inventors discovered that the first seal ring 17 adopts a hard polymer structure and is subjected to large pressure, so if a groove is provided directly on the piston side wall, the first seal ring 17 cannot be fixed. For this reason, a separate structure is adopted, and during assembly, the first seal ring is first placed on the top surface 212 of the body of the piston 21, and then the cover plate 20 is placed on it and tightened with the bolts 7. In some embodiments, in order to provide sufficient tightening force, the inclination angle of the one-sided oblique groove, i.e., the inclination angle of the inclined surface 201, is greater than 60°.

[0069] In some embodiments, the specific materials of the first seal ring 17 and the second seal ring 170 may be such that the polymer material of the first seal ring has a flexural modulus of 1.9GPa-3.6GPa, an elongation of 60%-120%, and a Knoop hardness of 90Hk-100Hk. Therefore, the first seal ring 17 should have a certain rigidity and be unlikely to undergo obvious deformation, and at the same time, have relatively good surface self-lubrication, and be compatible with relatively low compression shrinkage, as well as the ability of the abrasive grains to be well embedded in the material and continue to slide in the material after being embedded. The polymer material of the second seal ring 170 should satisfy the following requirements: flexural modulus of elasticity is 0.2 GPa to 0.25 GPa, elongation is 300% to 380%, and flexural strength is 80 to 100 MPa, so that the second seal ring 170 has relatively good elasticity and can undergo obvious expansion and contraction deformation. At the same time, it should have both the ability to seal aqueous materials with significant compression contraction length and very high flexural strength, otherwise it will be prone to break after bending during movement.

[0070] In some embodiments, the material of the first seal ring 17 may be one of pp, polytetrafluoroethylene, nylon, peek, and the material of the second seal ring 170 may be one of silica gel, rubber, nitrile, which are easy to obtain and low in cost.

[0071] 3, the second groove 211 may have at least two grooves including a first sub-groove 2111 and a second sub-groove 2111 from the top to the bottom, and the ratio of the depth of the second sub-groove 2112 to the depth of the first sub-groove 2111 is 1.2 to 1.5. Furthermore, a third sub-groove 2113 may be further opened toward the bottom of the second sub-groove 2112, or more sub-grooves may be further opened. The ratio of the depth of the second sub-groove 2112 to the depth of the third sub-groove 2113 is 1.2 to 1.5. The second seal rings 170 corresponding to the first sub-groove 2111, the second sub-groove 2112 and the third sub-groove 2113 are seal rings 16, 15 and 14 respectively, and their function is to seal water. The groove shape may be a trapezoidal groove which is easy to process and to fix the seal ring. The depth of the second sub-groove 2112 is greater than the adjacent first sub-groove 2111 and third sub-groove 2113. The beneficial effect is that it can provide reliable sealing against the fluid phase of the finishing medium in multiple stages, with the first sub-groove 2111 providing a rudimentary seal, the second sub-groove 2112 providing a complete seal, and the third sub-groove 2113 providing a guaranteed seal.

[0072] Continuing with FIG. 3, in some embodiments, the cylinder wall of the cylinder block 18 has a coating, the coating having a thickness of 50 μm-220 μm and a hardness of 1500 HV-2200 HV, the material being one or a combination of oxide, carbide, boride and nitride ceramics. Its beneficial effect is to ensure the reliability of the sealing effect. The principle is described. The inventors have found that during the operation of the device, in the process of high-speed movement of the two-phase flow of the fluid phase and the abrasive solid phase, the abrasive grains are mixed into the gap between the seal ring and the cylinder block and cause friction against the cylinder wall, and when the friction causes scratches on the cylinder wall, it will cause a complete failure of the sealing system and leakage of the fluid phase, so the cylinder wall must be hardened. The process of realizing the coating introduced above may solve the wear resistance of the cylinder wall by a special WC coating sprayed on the bore of the cylinder block. The specific components of the WC coating sprayed on the cylinder block are WC powder particle size 15-100μm, WC powder content more than 85%, molybdenum powder content 1%-4%, silicon powder content 1%-5%, boron powder content 1-5%, molybdenum silicon boron alloy phase is formed in the WC coating after spraying and sintering, molybdenum silicon boron alloy has a relatively low friction coefficient and is mixed into the WC coating as a reinforcing phase to increase the strength and hardness of the WC coating. The particle temperature during spraying is less than 1500℃, which reduces the amount of thermal deformation of the cylinder block after it is heated at a low temperature and ensures the dimensional accuracy of the final cylinder block. The spraying distance is 10mm-50mm, and the small spraying distance ensures the coating bonding force to be greater than 100MPa. In some embodiments, the surface roughness Ra of the coating is 0.05 μm to 0.4 μm, the cylinder block has a roundness of 100 μm or less and a cylindricity of 200 μm or less, and the diameter of the cylinder block is 100 mm to 400 mm, which prevents the relative movement of the piston and the cylinder block from generating a rolling force that scratches the coating and leads to peeling, and further ensures the life of the sealing system and the reliability of the sealing effect.The process for achieving this effect may involve surface honing of the coating, with a zirconia ceramic blade being used as the honing blade, and the honing rotation speed being less than 80 r / min. The relatively low rotation speed ensures that the coating does not peel off, chip or fall off during the honing process.

[0073] As still shown in FIG. 2, the finishing device 10 may further include a diagnostic device, which has a flow rate and / or flow rate sensor and a pressure sensor to sense the flow rate and / or flow rate of the finishing medium and the pressure to diagnose the state of the finishing process. The sensor only needs to be installed at a distance close to the upstream end of the workpiece 34, and the principle thereof will be described. The inventors have found that when the finishing process is performed normally, the flow rate / flow rate / pressure of the finishing medium at the upstream end of the fine internal flow passage is only affected by the internal flow passage structure and the surface quality of the internal flow passage. The flow resistance and flow rate of the internal flow passage itself will generate a reaction force and directly act on the flow rate / flow rate / pressure at the upstream end. Because the downstream end of the internal flow passage is larger than the cross-sectional area of ​​the internal flow passage, the polishing medium is in a state of "empty load" and freely flowing with respect to the downstream end after flowing out of the internal flow passage, and the downstream end of the internal flow passage does not affect the flow rate / flow rate / pressure at the upstream end. Therefore, the processing quality of the internal flow passage can be reflected just by measuring the change in the inlet velocity at the upstream end.

[0074] As for the pressure sensor, the data of the multi-port pressure gauge 29 is monitored in real time by the high-sensitivity piezoelectric quartz sensor 28 and the high-resolution multi-channel data collector 27, and the quasi-static and high-dynamic pressure process during the finishing process is completely recorded, so as to obtain accurate flow resistance data in each flow path and ensure the optimal finishing effect. The flow velocity and / or flow rate sensor includes the flow velocity flowmeter 24, the flow velocity flow piezoelectric sensor 25, and the flow velocity flow data collector 26, and adopts the ultrasonic measurement principle, and synchronizes the flow velocity flow rate of the multi-ports by the ultrasonic flowmeter based on the Doppler method principle. The ultrasonic is a non-contact measurement, which can completely avoid the two-phase flow from scratching the flow velocity flowmeter, greatly improving the response sensitivity of the entire system, and obtaining the optimal finishing time.

[0075] Although the present invention has been disclosed in the above embodiments, the present invention is not limited to the embodiments, and those skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention and the contents that do not deviate from the technical solution of the present invention are within the scope of protection defined in the claims of the present invention.

Claims

1. 1. A finishing device comprising: A thrust system; a plurality of sealing systems, each of which has a piston and a cylinder block mating with the piston for containing a finishing medium for performing finishing processing, the thrust system communicating with one end of the piston and providing a driving force to the sealing systems to push the finishing medium out of an outlet end of the cylinder block; The present invention provides a method for manufacturing a finishing medium supplying apparatus comprising: a plurality of conveying pipeline systems, each of which conveys the finishing medium contained in a corresponding sealed system to a different port of an internal flow path work for finishing, and a plurality of sealed systems communicate with each other via an internal flow path work; an upstream end of the conveying pipeline system is connected to an outlet end of the sealed system, and a downstream end of the conveying pipeline system discharges the finishing medium to the internal flow path work for finishing; a length-to-diameter ratio of the conveying pipeline system is greater than 10:1, and a diameter of the outlet end is greater than 3 mm; the conveying pipeline system has multiple pipelines, and a cross-sectional area ratio of the upstream pipeline to the downstream pipeline of two adjacent pipelines is greater than 1; wherein the thrust system of the finishing device includes a vertical plunger pump connected to the piston for providing a driving force for vertically moving the piston relative to a cylinder block; the multi-stage line includes a first stage line and a second stage line connected adjacent to the downstream of the first stage line, the first stage line including an elbow structure connected to an outlet end of the cylinder block, the elbow structure connected to a second stage line extending horizontally; a piston having at least a first groove and a second groove from the top to the bottom; the sealing system further comprising a seal ring located between the piston and a cylinder block, the seal ring including a first seal ring provided in the first groove and a second seal ring provided in the second groove; a radial gap between the piston and the cylinder block is 1 mm to 2.5 mm; the first groove is a separate structure; the top surface of the piston is flat and a cover plate is removably provided thereon; the cover plate has a slope on an outer periphery, the slope forms a one-sided oblique groove with the top surface of the piston to form the first groove; the second groove is opened in a side wall of the piston; and the first seal ring is made of a hard material and the second seal ring is made of a soft material.

2. 2. The finishing apparatus of claim 1, wherein a ratio of a cross-sectional area of ​​the first stage pipe to that of the second stage pipe is 1.2 to 1.

8.

3. The finishing apparatus according to claim 2, characterized in that the multi-stage pipeline further comprises a third stage pipeline connected adjacent to the downstream of the second stage pipeline, and a cross-sectional area ratio between the second stage pipeline and the third stage pipeline is 1.2 to 1.

8.

4. The finishing device described in claim 3, further comprising a tool having a port, wherein the cross-sectional area ratio between the third stage pipeline and the port of the tool is 1.2 to 2.2, and the cross-sectional area ratio between the port of the tool and the port of the workpiece internal flow path is 1.2 to 10.

5. 2. The finishing device of claim 1, wherein the second groove comprises at least two grooves from top to bottom, including a first sub-groove and a second sub-groove, and a ratio of a depth of the second sub-groove to a depth of the first sub-groove is between 1.2 and 1.

5.

6. 2. The finishing device of claim 1, wherein the angle of inclination of the one-sided oblique groove is greater than 60 degrees.

7. The finishing device according to claim 1, characterized in that the material of the first seal ring satisfies a flexural modulus of 1.9 GPa to 3.6 GPa, an elongation rate of 60% to 120%, and a Knoop hardness of 90 Hk to 100 Hk, and the material of the second seal ring satisfies a flexural modulus of 0.2 GPa to 0.25 GPa, an elongation rate of 300% to 380%, and a flexural strength of 80 MPa to 100 MPa.

8. 8. The finishing device of claim 7, wherein the material of the first seal ring is one of pp, polytetrafluoroethylene, nylon, and peek, and the material of the second seal ring is one of silica gel, rubber, and nitrile.

9. 2. The finishing device according to claim 1, characterized in that the cylinder wall of the cylinder block 1 has a coating, the coating having a thickness of 50 μm to 220 μm and a hardness of 1500 HV to 2200 HV, and being made of one or a combination of oxide, carbide, boride and nitride ceramics.

10. 10. The finishing device according to claim 9, wherein the surface roughness Ra of the coating is 0.05 μm to 0.4 μm, the roundness is 100 μm or less, and the cylindricity is 200 μm or less.

11. 10. The finishing device of claim 1 further comprising a diagnostic device, the diagnostic device having a flow rate and / or flow rate sensor and a pressure sensor for sensing the flow rate and / or flow rate and pressure of the finishing medium.

12. 2. The finishing device of claim 1, wherein the finishing medium has a liquid phase and a solid phase, the viscosity of the liquid phase is less than 1000 cP, the solid phase has abrasive grains, and the workpiece to be finished is a fine internal flow passage material, the aperture is 3 mm or less, and the length to diameter ratio is 50:1 or more.

13. A method for finishing an internal flow path material, comprising: using a finishing device according to any one of claims 1 to 12; the finishing medium has a liquid phase and a solid phase, the viscosity of the liquid phase is less than 1000 cP, the solid phase has abrasive grains, the workpiece to be finished is a fine internal flow path material, the diameter is 3 mm or less, and the length to diameter ratio is 50:1 or more; the thrust system of the finishing device applies a predetermined pressure to the finishing medium so that the finishing medium flows through the fine internal flow path at a flow velocity of greater than 5 m / s; and the flow rate of the finishing medium flowing into the interior of the fine internal flow path from one end thereof reaches a saturation value of the flow rate that can be accommodated by the diameter of the fine internal flow path so that the liquid pressure inside the internal flow path is in a pressure-trapping state.

14. A sealing system for use in a finishing device according to any one of claims 1 to 12, comprising: The piston is adapted to reciprocate along an extension direction of a cylinder wall of the cylinder block, and the piston is adapted to receive a finishing medium for finishing. The piston is adapted to reciprocate along an extension direction of a cylinder wall of the cylinder block. The thrust system is connected to one end of the piston and provides a driving force to the piston. wherein the piston has at least a first groove and a second groove from top to bottom, the sealing system further comprises a seal ring located between the piston and a cylinder block, the first seal ring being provided in the first groove and the second seal ring being provided in the second groove, and the radial gap between the piston and the cylinder block is 1 mm to 2.5 mm; The first groove is a separate structure, the top surface of the piston is flat, a cover plate is removably provided thereon, the cover plate has a slope on its outer periphery, the slope forms a one-sided diagonal groove with the top surface of the piston to form the first groove, and the second groove is opened in a side wall of the piston.

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