Contour polishing process suitable for slender pipe

Abstract

The invention discloses an outline polishing process suitable for a slender pipe, which comprises the following steps: firstly, erecting the slender pipe on a rolling support area formed by a plurality of rolling support wheel groups in a free rolling manner; secondly, left and right polishing strokes extending from the end part to the middle part are respectively formed based on the switching cooperation of downward pressing point positions formed by the polishing heads at the left and right ends of the slender pipe and the downward pressing wheel groups; on one hand, the grinding stroke covering the whole slender pipe is formed based on position switching of the pressing wheels, under one-time rotating positioning of the slender pipe, the slender pipe is kept in an axial dynamic balance mode, the contour surface is firstly ground step by step left and right and then ground synchronously, dead-corner-free grinding of the contour surface of the slender pipe is achieved, and the grinding efficiency is improved; the axis reference is kept consistent, and high-quality grinding without axial movement and radial run-out is implemented; on the other hand, axial dynamic balance assistance is formed based on the transverse moving speed difference of the left grinding head and the right grinding head, and the left grinding head and the right grinding head are synchronously separated from the slender pipe.

Description

[0001] This application is a divisional application filed on November 24, 2025, with application number 2025117276835, entitled "All-round grinding process applicable to the contour, end face and inner hole of slender tubes". Technical Field

[0002] This invention belongs to the field of polishing, and specifically relates to a contour polishing process suitable for slender tubes. Background Technology

[0003] Currently, conventional grinding of slender tubes requires multiple stages to achieve full-range grinding, such as contour surface grinding, end face grinding, and inner hole grinding. For contour surface grinding, due to the characteristics of the tube on-site, it's impossible to establish a fixed position from both ends to form an overall positioning, which creates a constraint. Therefore, contour surface grinding is divided into two steps: first, grinding half of the tube by moving from one end towards the positioning point; second, reversing the direction of the slender tube, with the positioning point acting on the already ground tube wall, and then grinding the other half by moving from the other end towards the positioning point. Therefore, the following technical drawbacks exist: 1) During the contour surface grinding process, not only is two positioning required, but the two positioning points cannot be the same. In other words, the reference formed by the two grinding steps cannot be consistent, which makes the grinding accuracy unable to meet the requirements, resulting in a very high scrap rate. At the same time, the whole operation process is also very cumbersome, and the contour surface grinding efficiency is also very low. 2) Although the contour surface grinding, end face grinding, and inner hole grinding are performed independently, the order of these three processes is very important. If the contour surface is not ground when grinding the inner hole, the radial runout of the slender tube caused by the contour surface will result in the grinding head and the center line of the slender tube not coinciding. This will not only prevent the complete grinding of the inner surface, but also increase the probability of local over-grinding, thus directly affecting the final grinding quality. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an improved contour grinding process suitable for slender tubes.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A contour grinding process suitable for slender tubes includes the following steps: First, the slender tube is freely rolled on the rolling support area formed by multiple rolling support wheel sets. The multiple rolling support areas are aligned to form a bearing area, and the center of the bearing area is aligned with the center of the slender tube. At the same time, with the center of the bearing area as a reference, pressure wheel sets that can be switched relative to each other are formed on opposite sides of the reference. The pressure wheel sets can roll and press down on the slender tube. Secondly, the switching and coordination of the grinding heads and pressure rollers at the left and right ends of the slender tube create left and right grinding strokes extending from the ends to the middle. These left and right grinding strokes overlap or align at the middle of the slender tube. Simultaneously, the rotation direction of the grinding heads is opposite to that of the slender tube. When grinding in the left stroke, the left grinding head moves to the middle of the slender tube, while the right grinding head contacts the right end of the slender tube, creating an axial dynamic balancing effect that generates opposing balancing forces, ensuring no axial displacement of the slender tube. Next, the left grinding head moves to the left to grind until it reaches the left end of the slender tube, and the grinding of the remaining end is paused. At the same time, the pressure point of the pressure wheel group is switched to implement the right grinding stroke. The right grinding head moves to the middle of the slender tube and moves to the right to grind. At this time, the left grinding head forms a balancing force in the opposite direction, so as to form an axial dynamic balance assistance without axial displacement of the slender tube. The lateral movement speed of the left grinding head is less than that of the right grinding head. The left and right grinding heads move towards each other and complete the left and right grinding strokes simultaneously and then move away from the slender tube simultaneously.

[0006] Preferably, the axial dynamic balancing aid is based on the grinding contact or reverse movement to form a balancing force in opposite directions.

[0007] According to a specific embodiment and preferred aspect of the invention, the two grinding heads rotate at equal speeds and in the same direction.

[0008] According to another specific embodiment and preferred aspect of the invention, each rolling support wheel assembly comprises two support wheels with parallel axes and spaced apart from each other. The rolling support formed by the double support wheels facilitates the rotation of the slender tube.

[0009] Preferably, one of the two support wheels is the driving wheel, and the other support wheel and the pressure wheel of the pressure wheel assembly are the following wheels. The rotation of the slender tube can be achieved based on a single power source.

[0010] Furthermore, the multiple drive wheels are coaxial. This allows a single motor to synchronously drive the heads of multiple drive wheels to rotate in unison.

[0011] In some specific embodiments, there are two rolling support roller sets, with the distance between the two rolling support roller sets being 1 / 3 to 1 / 2 of the length of the slender tube. The simplest support is formed by using the principle that two points determine a straight line, and the spacing layout can form better support based on the left and right grinding strokes to reduce the radial runout of the slender tube.

[0012] Preferably, the lower pressure roller assembly includes a frame, a left wheel seat and a right wheel seat that are respectively mounted on the frame for vertical movement, and a left lower pressure roller and a right lower pressure roller correspondingly mounted on the left wheel seat and the right wheel seat, wherein the movement of the left wheel seat and the right wheel seat switches so that one of the left lower pressure roller and the right lower pressure roller presses down onto the slender tube. In short, the switching of the wheel seats realizes the switching of the pressure rollers.

[0013] In some specific embodiments, the lower left and lower right pressure rollers are staggered between two sets of rolling support rollers. In the axial projection of the slender tube, one of the pressure rollers and both support rollers of the rolling support roller sets are tangent to the slender tube, and the centers of the pressure rollers and support rollers form an equilateral triangle, with the center of the equilateral triangle coinciding with the center of the slender tube. This staggered, triangular arrangement of the pressure rollers and the two sets of support rollers provides rotational positioning for the slender tube, preventing axial movement and radial runout.

[0014] Preferably, the frame includes a base frame and a shifting frame, wherein the shifting frame is mounted on the base frame in a direction parallel to the axis of the pressure roller, and the left wheel seat and the right wheel seat are slidably mounted on the shifting frame in the vertical direction.

[0015] Due to the implementation of the above technical solutions, the present invention has the following advantages compared with the prior art: In existing processes for grinding the contour surface of slender tubes, not only is two positioning steps required, but the points used for these two positioning steps cannot be identical. This means the reference points formed by the two grinding steps cannot be consistent, resulting in insufficient grinding accuracy, a very high scrap rate, and a cumbersome and inefficient grinding process. This application addresses these shortcomings by providing a comprehensive design for grinding the contour surface of slender tubes, cleverly resolving the deficiencies and defects of existing technologies. In this grinding process, the slender tube is first freely rolled on a rolling support area formed by multiple rolling support wheel sets. The multiple rolling support areas are aligned... A bearing area is formed, with its center aligned with the center of the slender tube. Simultaneously, using the center of the bearing area as a reference, opposing pressure roller sets are formed on opposite sides of the reference, allowing for relative switching. These pressure roller sets can roll and press down on the slender tube. Furthermore, the switching cooperation between the grinding heads at the left and right ends of the slender tube and the pressure roller sets creates left and right grinding strokes extending from the ends to the center. The left and right grinding strokes overlap or align at the center of the slender tube. Simultaneously, the rotation direction of the grinding heads is opposite to the rotation direction of the slender tube. When grinding in the left grinding stroke, the left grinding head moves to the center of the slender tube, and the right grinding head... The grinding head contacts the right end of the slender tube, creating an axial dynamic balancing assist that generates opposing balancing forces to prevent axial displacement of the tube. Then, the left grinding head moves to the left to grind until it reaches the left end of the tube, pausing grinding at the remaining end. Simultaneously, the pressure point of the pressure wheel group is switched to initiate the right grinding stroke. The right grinding head moves to the middle of the slender tube and grinds to the right. At this point, the left grinding head generates an opposing balancing force, ensuring axial dynamic balancing without displacement of the tube. The lateral speed of the left grinding head is less than that of the right grinding head, and the left and right grinding heads move in opposite directions simultaneously, completing the left and right grinding strokes synchronously. After the grinding stroke, the grinding head detaches synchronously from the slender tube. Therefore, compared with the prior art, this invention, on the one hand, forms a grinding stroke covering the entire slender tube based on the position switching of the pressure roller, and keeps the slender tube in an axial dynamic balance mode under the positioning of one rotation of the slender tube, so as to realize the contour surface is first ground in two steps and then simultaneously ground. This not only achieves grinding of the contour surface of the slender tube without dead angles, but also maintains the consistency of the axial reference to carry out high-quality grinding without axial movement and without radial runout. On the other hand, based on the difference in the lateral movement speed of the left and right grinding heads, not only is axial dynamic balance assistance formed, but the left and right grinding heads are also kept to detach synchronously from the slender tube. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the omnidirectional polishing machine for slender tubes in this embodiment; Figure 2 for Figure 1 Simplified structural diagram; Figure 3 for Figure 2 Simplified structural diagram; Figure 4 for Figure 3 Schematic diagram of the mid-contour surface grinding unit structure; Figure 5 for Figure 3 Schematic diagram of the mid-end surface grinding unit structure; Figure 6 for Figure 3 Schematic diagram of the inner hole grinding unit structure; Figure 7 for Figure 3 A simplified schematic diagram illustrating the principle of grinding the middle contour surface in the left grinding stroke; Figure 8 for Figure 3 A simplified schematic diagram illustrating the principle of grinding the middle contour surface during the right grinding stroke; Figure 9 for Figure 3 Simplified schematic diagram of the grinding principle of the middle end face; Figure 10 for Figure 3 Simplified schematic diagram of the grinding principle of the inner hole; The components are as follows: 1. Contour surface grinding unit; 10. Rolling support wheel assembly; 100. Support wheel; 101. Power unit; 11. Lower pressure wheel assembly; 110. Frame; a. Base frame; b. Transfer frame; 111. Left wheel seat; 112. Right wheel seat; 113. Left lower pressure wheel; 114. Right lower pressure wheel; 12. Grinding head; 12L. Left grinding head; 12R. Right grinding head; 2. End face grinding unit; 20. Rolling frame wheel assembly; 200. Frame wheel; 21. Positive pressure wheel assembly; 210. Positive pressure wheel; 211. Power unit; 22. Grinding head; 3. Internal hole grinding unit; 30. Rolling wheel assembly; 300. Roller; 31. Clamping wheel assembly; 310. Clamping wheel; 311. Power unit; 32. Internal grinding head; G. Slender tube; S. Transverse manipulator; s1. Transfer gripper. Detailed Implementation

[0017] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0018] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0020] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0021] In this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0023] like Figures 1 to 10 As shown, the omnidirectional grinding process applicable to the contour, end face, and inner hole of slender tubes in this embodiment uses omnidirectional grinding equipment including contour grinding unit 1, end face grinding unit 2, and inner hole grinding unit 3.

[0024] Specifically, the contour grinding unit 1 includes two rolling support wheel sets 10, a pressure wheel set 11, and two grinding heads 12. Each rolling support wheel set 10 includes two support wheels 100 with parallel axes and spaced apart from each other, and a power component 101. The rolling support formed by the two support wheels 100 facilitates the rotation of the slender tube G. In this example, one of the two support wheels 100 is a driving wheel, and the other is a driven wheel (or follower wheel). The driving wheels of the two rolling support wheel sets 10 are connected by a synchronous shaft and then driven by the power component 101 (using a conventional motor and drive belt). The distance between the two rolling support wheel sets 10 is 1 / 3 to 1 / 2 of the length of the slender tube G. The simplest support is formed by using the principle of two points determining a straight line, and the distance layout can form better support based on the left and right grinding strokes to reduce the radial runout of the slender tube. The pressure roller assembly 11 includes a frame 110, a left wheel seat 111 and a right wheel seat 112 mounted on the frame 110 for vertical movement, a left pressure roller 113 and a right pressure roller 114 mounted on the left wheel seat 111 and right wheel seat 112 respectively, and a pressure drive. The movement of the left wheel seat 111 and right wheel seat 112 switches so that one of the left pressure roller 113 and right pressure roller 114 presses down onto the slender tube G. Both the left pressure roller 113 and right pressure roller 114 are driven rollers (or follower rollers). In short, the switching of the wheel seats achieves the switching of the pressure rollers. The frame 110 includes a base frame a and a shifting frame b. The shifting frame b is mounted on the base frame a and can be moved laterally along a direction parallel to the axis of the pressure roller. The left wheel seat 111 and the right wheel seat 112 are slidably mounted on the shifting frame b in the vertical direction, respectively. At the same time, the pressing power unit is used to drive the frame 110 to move laterally toward or away from the slender tube G, and to drive the left wheel seat 111 or the right wheel seat 112 to move up and down to achieve pressing and disengagement movements. It is driven by conventional pneumatic cylinders, hydraulic cylinders or electric cylinders, and is guided by corresponding slide rails. The lower left pressure roller 113 and the lower right pressure roller 114 are offset between the two rolling support roller sets 10. In the axial projection of the slender tube G, one of the pressure rollers 113 and 114, along with the two support rollers 100 of the rolling support roller set 10, are tangent to the slender tube G. The center of the pressure roller and the center of the support roller 100 form an equilateral triangle, with the center of the equilateral triangle coinciding with the center of the slender tube G. Based on the offset and triangular layout of the pressure rollers and the two sets of support rollers, the slender tube is rotated and positioned, preventing axial movement and radial runout. The two grinding heads 12 rotate at equal speeds in the same direction, but their rotation direction is opposite to that of the slender tube G. Each grinding head 12 can not only rotate around its own axis but also move along the axial direction.

[0025] The end-face grinding unit 2 includes a rolling frame wheel assembly 20, a pressure wheel assembly 21, and two grinding heads 22. The rolling frame wheel assembly 20 has the same structure as the rolling support wheel assembly 10. The pressure wheel assembly 21 includes a pressure wheel 210 aligned with the rolling frame wheel assembly 20 and a power unit 211 (using a conventional pneumatic cylinder, hydraulic cylinder, or electric cylinder, and guided by a corresponding slide rail) that drives the pressure wheel 210 to press down or disengage. The pressure wheel 210 and the two support wheels 200 of the rolling frame wheel assembly 20 are arranged in an equilateral triangle, with the center of the equilateral triangle coinciding with the center of the slender tube G. One of the pressure wheel 210 and / or the support wheel 200 is the driving wheel, and the others are driven wheels. In this case, there is no need to switch the pressure wheel position, so end-face grinding is performed based on two-point rotation positioning to keep the slender tube in a straight position. The two grinding heads 22 rotate at the same speed and in the same direction. At the same time, the rotation direction of the grinding heads 22 is opposite to the rotation direction of the slender tube G. Each grinding head 22 can not only rotate around its own axis, but also move along the axis.

[0026] The internal grinding unit 3 includes a rolling wheel assembly 30, a clamping wheel assembly 31, and two internal grinding heads 32. The rolling wheel assembly 30 has the same structure as the rolling support wheel assembly 10. The clamping wheel assembly 31 includes a clamping wheel 310 aligned with the rolling wheel assembly 30 and a power component 311 (using a conventional pneumatic cylinder, hydraulic cylinder, or electric cylinder, and guided by a corresponding slide rail) that drives the clamping wheel 310 to press down or disengage. The clamping wheel 310 and the two rollers 300 of the rolling wheel assembly 30 are arranged in an equilateral triangle, with the center of the equilateral triangle coinciding with the center of the slender tube G. One of the clamping wheel 310 and / or one of the rollers 300 is the driving wheel, and the others are driven wheels. In this case, there is no need to switch the position of the pressure rollers; therefore, internal grinding is performed based on two-point rotation positioning to keep the slender tube in a straight position. The two internal grinding heads 32 rotate at the same speed and in the same direction. At the same time, the rotation direction of the internal grinding heads 32 is opposite to the rotation direction of the slender tube G. Each internal grinding head 32 can not only rotate around its own axis, but also move along the axis.

[0027] Furthermore, the contour grinding, end face grinding, and inner hole grinding are arranged sequentially and alternately, and a traversing robot S is used with transfer grippers s1 corresponding to the three grinding areas. The transfer grippers s1 can simultaneously hold the slender tube G located in each grinding area, and continuous transfer of the grinding process can be achieved with a single shift. The traversing robot S quickly connects multiple grinding areas and more accurately completes the center-aligned rotational positioning of the slender tube.

[0028] In this example, the all-around polishing process includes the following sequential polishing steps: S1, Contour Polishing First, the slender tube G is freely rolled on a rolling support area formed by multiple rolling support wheel sets 10. These rolling support areas are aligned to form a bearing area, with the center of the bearing area aligned with the center of the slender tube G. Simultaneously, using the center of the bearing area as a reference, pressing wheel sets 11 are formed on opposite sides of the reference, capable of relative switching and rolling downwards onto the slender tube G. The pressing points formed by the pressing wheel sets 11 and the bearing area cooperate to form a positioning channel. The slender tube G is driven to rotate around its own axis within the positioning channel based on the pressing wheel sets 11 and the rolling support wheel sets 10. Second, based on the switching cooperation between the grinding heads 12 at the left and right ends of the slender tube G and the pressing points formed by the pressing wheel sets 11, left and right pressing points extending from the ends towards the center are respectively formed. The right grinding stroke overlaps with the left and right grinding strokes in the middle of the slender tube G. At the same time, the rotation direction of the grinding head 12 is opposite to that of the slender tube G. During the left grinding stroke, the left grinding head 12L moves to the middle of the slender tube G, and the right grinding head 12R contacts the right end of the slender tube G to form an axial dynamic balance assist. Then, the left grinding head 12L moves to the left to grind and reaches the left end of the slender tube G, and the remaining end stops grinding. At the same time, the pressure point of the pressure wheel group 11 is switched to implement the right grinding stroke. The right grinding head 12R moves to the middle of the slender tube G and moves to the right to grind. At this time, the left grinding head 12L forms an axial dynamic balance assist, and the left and right grinding strokes are completed synchronously while the left and right grinding heads move in opposite directions. S2, End face grinding The slender tube with the profile surface ground is transferred to the end face grinding area, and then grinding is performed by grinding heads at both ends synchronously, with the grinding heads and the slender tube rotating in opposite directions, to complete the end face grinding. S3, Inner hole grinding The slender tube with the end face ground is transferred to the inner hole grinding area. Then, the inner grinding heads at both ends are used to grind the inner hole of the slender tube synchronously with the inner grinding heads and the slender tube rotating in opposite directions. When the two inner grinding heads are close to each other, one continues to move forward while the other moves backward so that the grinding covers the entire inner hole. Then, the two inner grinding heads move out in the opposite direction to complete the inner hole grinding.

[0029] Furthermore, in step S1, rolling support is formed based on the double support wheels 100 to facilitate the rotation of the slender tube G. Axial dynamic balancing assistance is based on grinding contact or reverse movement to form opposing balancing forces, so that the slender tube G can be ground on the contour surface without axial displacement. Axial dynamic balancing further reduces axial movement of the slender tube during the grinding of the contour surface. The two grinding heads 12 rotate at equal speeds and in the same direction. Rotation is avoided to prevent axial movement of the slender tube. When the left grinding head 12L forms axial dynamic balancing assistance, the lateral movement speed of the left grinding head 12L is less than that of the right grinding head 12R, and the two keep synchronously disengaging from the slender tube. This also further avoids axial movement of the slender tube during contour surface grinding.

[0030] In step S2, circumferential rotation positioning is achieved using the rolling frame wheel assembly 20 and the positive pressure wheel assembly 21. This rotational positioning eliminates axial movement of the slender tube during end-face grinding. The grinding head 22 rotates in the same direction and at the same speed. This prevents axial movement of the slender tube from occurring during end-face grinding.

[0031] In step S3, circumferential rotational positioning is achieved using the rolling wheel set 30 and the clamping wheel set 31. This rotational positioning eliminates axial movement of the slender tube during internal grinding. The two internal grinding heads 32 rotate in the same direction, with equal grinding and movement speeds. This same speed and direction of rotation prevents torsion and uneven axial stress in the slender tube during synchronous grinding. The grinding areas formed during the counter-movements of the two internal grinding heads 32 overlap. This overlap ensures that the grinding area fully covers the entire inner hole of the slender tube.

[0032] In summary, after adopting this grinding process, firstly, the slender tube is freely rolled on a rolling support area formed by multiple rolling support wheel sets. These rolling support areas are aligned to form a bearing area, with the center of the bearing area aligned with the center of the slender tube. Simultaneously, using the center of the bearing area as a reference, pressure wheel sets are formed on opposite sides of the reference, capable of relative switching and rolling downwards onto the slender tube. The pressure points formed by the pressure wheel sets and the bearing area cooperate to form a positioning channel. The slender tube rotates around its own axis within the positioning channel based on the pressure wheel sets and / or the rolling support wheel sets. Next, the switching and cooperation of the grinding heads at the left and right ends of the slender tube and the pressure points formed by the pressure wheel sets respectively create left and right grinding strokes extending from the ends towards the middle, with the left and right grinding strokes overlapping in the middle of the slender tube. Alternatively, the grinding heads can be aligned and joined together, with the rotation direction of the grinding heads opposite to that of the slender tube. During the left grinding stroke, the left grinding head moves to the middle of the slender tube, while the right grinding head contacts the right end of the slender tube to provide axial dynamic balance. Then, the left grinding head moves to the left to grind until it reaches the left end of the slender tube, pausing grinding at the remaining end. Simultaneously, the pressure point of the pressure wheel group is switched to initiate the right grinding stroke. The right grinding head moves to the middle of the slender tube and grinds to the right. At this time, the left grinding head provides axial dynamic balance, and the left and right grinding strokes are completed synchronously as the left and right grinding heads move in opposite directions to complete the contour surface grinding. Next, the slender tube with the contour surface ground is transferred to the end face grinding area, and then grinding is performed synchronously by the grinding heads at both ends, with the grinding heads and the slender tube rotating in opposite directions. The end face grinding is completed. Finally, the slender tube with the end face ground is transferred to the inner hole grinding area. Then, two inner grinding heads are used simultaneously, with the inner grinding heads and the slender tube rotating in opposite directions, to grind the inner hole of the slender tube. When the two inner grinding heads are close to each other, one continues to move forward while the other moves backward so that the grinding covers the entire inner hole. Then, they move out in the opposite direction to complete the inner hole grinding. Therefore, compared with the prior art, this invention, on the one hand, forms a grinding stroke covering the entire slender tube based on the position switching of the pressure roller, and on the other hand, keeps the slender tube in an axial dynamic balance mode under the positioning of one rotation of the slender tube. It realizes that the contour surface is first ground in two steps and then synchronously. This not only achieves grinding of the contour surface of the slender tube without dead angles, but also maintains the consistency of the axial reference to carry out high-quality grinding without axial movement and without radial runout. On the other hand, based on the sequential grinding of the contour surface, end face, and inner hole of the slender tube, not only is the radial runout defect caused by the contour surface during inner hole grinding eliminated, but also the rotation center of the slender tube is further corrected based on the centering grinding of the end face, providing the necessary conditions for high-quality inner hole grinding, so as to complete the all-round grinding of the slender tube with high efficiency and yield. On the third aspect, the rolling support formed by the double support wheels is used to facilitate the rotation of the slender tube. One of the two support wheels is the driving wheel, and the other support wheel and the lower pressure wheel of the lower pressure wheel group are the follower wheels. At the same time, the two driving wheels are coaxial, so that a power motor can synchronously drive multiple driving wheel heads to rotate synchronously. In addition, there are two rolling support wheel groups, and the distance between the two rolling support wheel groups is 1 / 3 to 1 / 2 of the length of the slender tube.The simplest support is formed by using the principle of two points determining a straight line, and the distance layout can form better support based on the left and right grinding strokes to reduce the radial runout of slender tubes; fourthly, the switching of the wheel seat realizes the switching of the pressure wheel, and the pressure wheel with a staggered and overall triangular layout and two sets of support wheels form the rotational positioning of the slender tube, avoiding axial movement and radial runout of the slender tube; at the same time, axial dynamic balance further reduces the axial movement of the slender tube in the grinding profile surface; fifthly, the two grinding heads rotate at equal speeds and in the same direction to avoid axial movement of the slender tube caused by rotation; the left grinding head forms the shaft During dynamic balancing, the lateral movement speed of the left grinding head is less than that of the right grinding head, and both move out of the slender tube synchronously. This further avoids axial movement of the slender tube during contour grinding. Sixthly, a rolling frame wheel assembly and a positive pressure wheel assembly are used for circumferential rotation positioning. Based on rotation positioning, axial movement of the slender tube during end face grinding is eliminated. The rolling frame wheel assembly has the same structure as the rolling support wheel assembly. The positive pressure wheel assembly includes a positive pressure wheel aligned with the rolling frame wheel assembly and a power unit that drives the positive pressure wheel to press down or disengage. The positive pressure wheel and the two frame wheels of the rolling frame wheel assembly are distributed in an equilateral triangle, and the center of the equilateral triangle is aligned with the slender tube. With the centers coinciding and based on either the pressure roller or the support roller being the driving roller, and the others being driven rollers, there is no need to switch the pressure roller positions. A two-point rotational positioning method is used to keep the slender tube in a straight position during end-face grinding. Simultaneously, the grinding heads rotate in the same direction and at the same speed to avoid axial movement of the slender tube during end-face grinding. The seventh aspect uses a rolling roller group and a clamping roller group for circumferential rotational positioning. This rotational positioning eliminates axial movement of the slender tube during internal hole grinding. The rolling roller group has the same structure as the rolling support roller group, and the clamping roller group includes a clamping roller aligned with the rolling roller group, a drive clamping roller to press down, or... The detached power components, the two rollers of the clamping roller and rolling roller group are distributed in an equilateral triangle, and the center of the equilateral triangle coincides with the center of the slender tube. Based on the fact that one of the clamping roller and / or the roller is the driving roller and the others are driven rollers, at this time, there is no need to switch the position of the clamping roller. The two-point rotation positioning is directly adopted to keep the slender tube in a straight state for internal hole grinding. In the eighth aspect, the two internal grinding heads rotate in the same direction, and the grinding speed and the moving speed are equal. Based on the same speed and the same direction of rotation, the torsion of the slender tube and the unequal axial stress caused by synchronous grinding are avoided. At the same time, the grinding areas formed by the opposite movement of the two internal grinding heads overlap. The overlapping ensures that the grinding area fully covers the inner hole of the entire slender tube; the ninth aspect involves the sequential and alternating arrangement of contour grinding, end face grinding, and inner hole grinding, and the use of a transverse robot with transfer grippers corresponding to the three grinding areas. The transfer grippers can simultaneously hold the slender tube located in each grinding area, and the grinding process can be continuously transferred with a single shift. The transverse robot can quickly connect multiple grinding areas and more accurately complete the center-aligned rotational positioning of the slender tube.

[0033] The present invention has been described in detail above, with the aim of enabling those skilled in the art to understand and implement the invention. However, this description should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be included within the scope of protection of the invention.

Claims

1. A contour grinding process suitable for slender tubes, characterized in that, It includes the following steps: First, the slender tube is freely rolled on the rolling support area formed by multiple rolling support wheel sets. The multiple rolling support areas are aligned to form a bearing area, and the center of the bearing area is aligned with the center of the slender tube. At the same time, with the center of the bearing area as a reference, pressure wheel sets that can be switched relative to each other are formed on opposite sides of the reference. The pressure wheel sets can roll and press down on the slender tube. Secondly, the switching and coordination of the grinding heads and pressure rollers at the left and right ends of the slender tube create left and right grinding strokes extending from the ends to the middle. These left and right grinding strokes overlap or align at the middle of the slender tube. Simultaneously, the rotation direction of the grinding heads is opposite to that of the slender tube. When grinding in the left stroke, the left grinding head moves to the middle of the slender tube, while the right grinding head contacts the right end of the slender tube, creating an axial dynamic balancing effect that generates opposing balancing forces, ensuring no axial displacement of the slender tube. Next, the left grinding head moves to the left to grind until it reaches the left end of the slender tube, and the grinding of the remaining end is paused. At the same time, the pressure point of the pressure wheel group is switched to implement the right grinding stroke. The right grinding head moves to the middle of the slender tube and moves to the right to grind. At this time, the left grinding head forms a balancing force in the opposite direction, so as to form an axial dynamic balance assistance without axial displacement of the slender tube. The lateral movement speed of the left grinding head is less than that of the right grinding head. The left and right grinding heads move towards each other and complete the left and right grinding strokes simultaneously and then move away from the slender tube simultaneously.

2. The contour grinding process for slender tubes according to claim 1, characterized in that, Axial dynamic balancing assistance is based on the formation of balancing forces in opposite directions through grinding contact or reverse movement.

3. The contour grinding process for slender tubes according to claim 1, characterized in that, The two grinding heads rotate at the same speed and in the same direction.

4. The contour grinding process for slender tubes according to claim 1, characterized in that, Each set of rolling support wheels used includes two support wheels with parallel axes and relatively spaced apart.

5. The contour grinding process for slender tubes according to claim 4, characterized in that, One of the two support wheels is the driving wheel, and the other support wheel and the pressure wheel of the pressure wheel assembly are the following wheels.

6. The contour grinding process for slender tubes according to claim 5, characterized in that, Multiple drive wheels are coaxial.

7. The contour grinding process for slender tubes according to claim 4, 5, or 6, characterized in that, There are two rolling support wheel sets, and the distance between the two rolling support wheel sets is 1 / 3 to 1 / 2 of the length of the slender tube.

8. The contour grinding process for slender tubes according to claim 7, characterized in that, The lower pressure roller assembly includes a frame, a left wheel seat and a right wheel seat that are respectively mounted on the frame for vertical movement, and a left lower pressure roller and a right lower pressure roller that are respectively mounted on the left wheel seat and the right wheel seat. The movement of the left wheel seat and the right wheel seat is switched so that one of the left lower pressure roller and the right lower pressure roller presses down on the slender tube.

9. The contour grinding process for slender tubes according to claim 8, characterized in that, The lower left and lower right pressure rollers are staggered between the two rolling support roller groups. In the axial projection of the slender tube, one of the pressure rollers and the two support rollers of the rolling support roller group are tangent to the slender tube. The center of the pressure roller and the center of the support roller form an equilateral triangle, and the center of the equilateral triangle coincides with the center of the slender tube.

10. The contour grinding process for slender tubes according to claim 9, characterized in that, The frame includes a base frame and a shifting frame, wherein the shifting frame is mounted on the base frame and can be moved laterally along a direction parallel to the axis of the pressure roller, and the left wheel seat and the right wheel seat are slidably mounted on the shifting frame along the vertical direction, respectively.

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