CN-121989171-A - Bearing deep hole inner surface controllable cavitation polishing strengthening device and processing method

CN121989171ACN 121989171 ACN121989171 ACN 121989171ACN-121989171-A

Abstract

The invention discloses a controllable cavitation polishing strengthening device for the inner surface of a deep hole of a bearing and a processing method, wherein an ultrasonic cavitation vibrating ring drives a magnetic powder storage ring to synchronously vibrate, a flaring angle cavitation nozzle downwards sprays an external expansion jet flow, when the spiral flowing jet flow passes through the ultrasonic cavitation vibrating ring, cavitation is induced to be primary and the gas content of the jet flow is improved, a magnetic powder storage ring hole is vibrated out and is curled into the jet flow, and spiral wall-attached jet flow preferentially acts on the inner surface of the upper part of the deep hole to polish and strengthen the upper part of the deep hole; when the spiral wall-attached jet spreads downwards to the lower part of the deep hole, the straight jet ejected from the cavitation nozzle without expansion angle compensates the fluid in the lower part of the deep hole and forms shearing and disturbance with the spiral wall-attached jet above to strengthen the polishing and strengthening of the lower part of the deep hole, and the electromagnetic coil keeps the stable movement speed of the magnetic powder in different axial positions to realize polishing strengthening integration.

Inventors

HE PEIYU
Sang Runchi
YANG CHENG
CAO FUYANG
ZHANG CHUNBO
LIANG WU
GONG MAOLIN
WANG WEIBO

Assignees

江苏大学

Dates

Publication Date: 20260508
Application Date: 20260325

Claims (10)

1. The controllable cavitation polishing strengthening device for the inner surface of the deep hole of the bearing is characterized in that a coaxial expanding angle cavitation nozzle (1) is arranged right above the deep hole to be processed, and a coaxial non-expanding angle cavitation nozzle (14) is arranged right below the deep hole to be processed; the device comprises a divergent angle cavitation nozzle (1), a diversion cone (2) with a small upper part and a large lower part, wherein the outer diameter of the upper part of the diversion cone (2) is smaller than the outer diameter of the outlet of the divergent angle cavitation nozzle (1), and the outer diameter of the lower end of the diversion cone is smaller than the aperture of a processed deep hole; The inner wall of the magnetic powder storage ring (4) is circumferentially provided with a plurality of radial storage ring holes (5) communicated with the magnetic powder storage space (6), and the magnetic powder storage ring (4), the ultrasonic cavitation vibration ring (7) and the guide cone (2) are all provided with intervals for jet flow to pass through in the radial direction; The cold flow ring (9), the heat insulation ring (10) and the hot flow ring (11) are wound on the outer side wall of the deep hole to be processed from top to bottom, and the peripheries of the cold flow ring (9), the heat insulation ring (10) and the hot flow ring (11) are conical electromagnetic coils (13) with large upper parts and small lower parts.
2. The device for enhancing the controllable cavitation polishing of the inner surface of the deep hole of the bearing is characterized in that a cold flow ring (9), a heat insulation ring (10) and a hot flow ring (11) are installed in an axial partition mode, the cold flow ring (9) is of a spring-shaped coating structure at the upper section of the deep hole to be processed, the heat insulation ring (10) is arranged at the middle section of the deep hole to be processed, and the hot flow ring (11) is of a spring-shaped coating structure at the deep hole (8) to be processed.
3. The device for enhancing the controllable cavitation polishing of the inner surface of the deep hole of the bearing according to claim 2 is characterized in that the axial positions of the cold flow ring (9) and the hot flow ring (11) are adjustable, and the separation position of the heat insulation ring (10) is correspondingly changed along with the axial adjustment of the cold flow ring (9) and the hot flow ring (11).
4. The device for enhancing the controllable cavitation polishing of the inner surface of a deep hole of a bearing according to claim 1, wherein the inside of the angle-expanding cavitation nozzle (1) is provided with a stepped through hole, the upper part is provided with a large hole section, the lower part is provided with a small hole section, the outlet end at the lower end is provided with an expanding section to form an angle-expanding, the angle-expanding cavitation nozzle (1) is communicated with an external liquid supply system, the liquid supply pressure is adjustable, and the external expanding jet is sprayed.
5. The device for enhancing the controllable cavitation and polishing of the inner surface of a deep hole of a bearing according to claim 1, wherein the cavitation nozzle (14) without a divergence angle is internally provided with a stepped through hole, the upper outlet section is a large-hole straight through hole, the lower section is a small-hole section, and a direct jet is sprayed.
6. The device for enhancing the controllable cavitation polishing of the inner surface of a deep hole of a bearing, which is disclosed in claim 1, is characterized in that the whole of a guide cone (2) is in a revolving body structure, the guide cone (2) is formed by connecting a conical section and a lower cylindrical section which are gradually enlarged from top to bottom, a transition section is provided with a round corner to enable the outer surface of the guide cone (2) to be smooth continuously, and the lower end of the guide cone (2) is connected with a guide cone bracket (3).
7. The device for strengthening the controllable cavitation polishing of the inner surface of a deep hole of a bearing according to claim 1, wherein one side of a storage ring hole (5) close to a magnetic powder storage space (6) is an expansion hole section, the expansion hole section is contracted inwards in the radial direction and is communicated with a through hole, the through hole is opened towards a central shaft of the deep hole to be processed, and a channel for guiding magnetic powder into a reaming hole and guiding powder out of the through hole is formed.
8. A method of processing a bearing deep hole inner surface controllable cavitation polishing enhancement device as claimed in any one of claims 1 to 7, wherein: Starting a cold flow ring (9), a hot flow ring (11), an electromagnetic coil (13) and an ultrasonic cavitation vibration ring (7), wherein the ultrasonic cavitation vibration ring (7) drives a magnetic powder storage ring (4) to vibrate synchronously, and simultaneously starting a divergent angle cavitation nozzle (1) and a non-divergent angle cavitation nozzle (14); The expansion angle cavitation nozzle (1) sprays outward expansion jet flow downwards, the jet flow enters the area of the guide cone (2) to deflect and form spiral flow, the spiral flow jet flow induces cavitation initiation and improves jet flow gas content when passing through the ultrasonic cavitation vibration ring (7), The jet forms a local low-pressure area when passing through the inner diameter of the magnetic powder storage ring (4), the magnetic powder is sucked into the storage ring hole (5) under the combined action of vibration and low-pressure suction, and is vibrated out of the storage ring hole (5) and sucked into the jet, so that the jet forms a spiral wall-attached jet in a gas, liquid and solid three-phase coupling state, The spiral wall-attached jet flow preferentially acts on the inner surface of the upper part of the deep hole, cavitation bubbles and magnetic powder firstly cover the deep hole opening and the upper area, and polishing and strengthening of the upper part of the deep hole are realized under the combined action of cavitation bubble collapse, magnetic powder scouring and jet flow impact; The spiral wall-attached jet flow continues to extend towards the middle along the hole wall to form a continuous effect, so that the polishing strengthening process is continuously unfolded from the upper part to the middle; when the spiral wall-attached jet flows downwards spread to the lower part of the deep hole, the straight jet flow sprayed out of the non-expansion angle cavitation nozzle (14) compensates the fluid in the lower part of the deep hole, and forms shearing and disturbance with the spiral wall-attached jet flow above, thereby enhancing the polishing and strengthening of the lower part of the deep hole; The electromagnetic coil (13) keeps the magnetic powder (17) at a stable moving speed at different axial positions.
9. The method of claim 8, wherein the axial positions of the cold flow ring (9), the heat insulating ring (10) and the hot flow ring (11) are changed to change the collapse position of cavitation bubbles in the deep hole to be processed and the release area of cavitation energy.
10. The method of claim 8, wherein the cone (2) is adjusted downward in the direction of the central axis, the intensity of the spiral jet entering the deep hole to be processed is reduced, and the polishing is enhanced.

Description

Bearing deep hole inner surface controllable cavitation polishing strengthening device and processing method Technical Field The invention relates to the technical field of polishing and strengthening processing of inner surfaces of holes, in particular to a device and a processing method for controllably polishing and strengthening the inner surfaces of deep holes by utilizing cavitation effect, which are applied to processing of liquid supply holes, orifices and related inner runner structures of bearings, particularly precision fluid supporting parts such as hydrostatic bearings. Background With the sustainable development of the fields of aerospace, energy equipment, precision manufacturing and the like, deep hole parts are widely applied to key parts such as fluid transportation, cooling, sealing, structural connection and the like. Deep holes are generally holes with a ratio of hole depth to diameter greater than 5, and are a type of hole pattern with higher difficulty in machining. The quality of the inner surface of the deep hole has important influence on hydrodynamic characteristics, structural reliability and service life. However, the hole parts generally have the characteristics of small aperture, large depth-diameter ratio, limited internal space and the like, the traditional processing mode is difficult to form stable, controllable and fully covered action environments in the holes, the polishing and strengthening process often depends on a single action mode, and the problems of limited action area, uneven energy distribution and obvious change of processing effects along with the positions easily occur. Under the working conditions of high pressure, high-speed flow or alternating load, the residual microscopic defects on the inner surface of the hole are easy to induce local stress concentration and flow disturbance, so that the abrasion is aggravated and even the early failure is caused. Therefore, there is an urgent need for a device for processing the inner surface of a deep hole type workpiece to be processed, particularly for processing the inner surface of a hole structure related to a bearing and a hydrostatic bearing, so as to realize controllable polishing and strengthening of the inner surface of the hole. At present, aiming at polishing and strengthening processing of the inner surface of a deep hole, the prior art mostly adopts the modes of mechanical polishing, abrasive flow polishing, water jet flow and the like for treatment. In deep hole parts with smaller apertures and larger deep diameters, the problems that an acting medium is difficult to fully enter the deep part in the deep hole, a processing area is limited, energy distribution is uneven and the like generally exist, and local overpolishing or insufficient polishing is easy to occur, so that the quality of the inner surface of the deep hole is not uniformly distributed along the axial direction and the radial direction, and the requirement of processing the inner surface of the deep hole with high consistency is difficult to meet. Cavitation is the physical phenomenon that fluid forms cavitation when the local pressure is reduced below the saturated vapor pressure, and in the collapse process, high-strength impact load and microjet flow act on the wall surface in an instant release mode. The cavitation effect is introduced into the deep hole for processing the inner surface, and the polishing and surface strengthening of the inner wall of the deep hole can be realized under the condition of not depending on the direct contact of a solid tool. However, due to long and narrow pore canal of the deep hole and long flow path, the cavitation jet flow is easy to gradually attenuate the action intensity in the process of propagating towards the inside of the deep hole, the generation position and collapse behavior of cavitation bubbles are difficult to effectively regulate and control in the inside of the deep hole, the cavitation energy is unevenly distributed along the axial direction of the hole, the problem of local overpolishing or insufficient polishing still easily occurs, and the application of the cavitation technology in the polishing strengthening of the inner surface of the deep hole is limited. In the document of chinese patent publication No. CN105563240a, entitled "a self-pressurizing high-speed abrasive flow hole inner surface polishing device", an abrasive flow hole inner surface polishing device is proposed, which is composed of a fluid pressurizing accelerating cavity, a piston cylinder, a piston rod and a driving unit, and uses a high-speed abrasive flow to polish the inner surface, however, the device can only polish the inner surface of a pipe, and in order to improve the mechanical properties of the pipe, the subsequent surface strengthening is still required. In the document of chinese patent publication No. CN104149036a, entitled "an abrasive flow microporous polishing apparatus and polishing process