CN109955156B - Tool for finely machining inner surface of pipe fitting - Google Patents
Tool for finely machining inner surface of pipe fitting Download PDFInfo
- Publication number
- CN109955156B CN109955156B CN201910372909.2A CN201910372909A CN109955156B CN 109955156 B CN109955156 B CN 109955156B CN 201910372909 A CN201910372909 A CN 201910372909A CN 109955156 B CN109955156 B CN 109955156B
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- CN
- China
- Prior art keywords
- guiding
- pipe fitting
- elements
- smooth
- smoothing
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B29/00—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents
- B24B29/02—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces
- B24B29/06—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces for elongated workpieces having uniform cross-section in one main direction
- B24B29/08—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces for elongated workpieces having uniform cross-section in one main direction the cross-section being circular, e.g. tubes, wires, needles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D5/00—Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor
- B24D5/06—Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor with inserted abrasive blocks, e.g. segmental
- B24D5/063—Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor with inserted abrasive blocks, e.g. segmental with segments embedded in a matrix which is rubbed away during the grinding process
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
- B24D5/00—Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting only by their periphery; Bushings or mountings therefor
- B24D5/16—Bushings; Mountings
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Drilling And Boring (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The invention discloses a jig for finely processing the inner surface of a pipe fitting, which solves the problem that the inner surface of the pipe fitting cannot be finely processed, and comprises three guide smooth elements, wherein two guide smooth elements can move, when in operation, the three guide smooth elements act on the inner surface of the pipe fitting through sliding friction, and the smooth force generated by the two movable guide smooth elements can be changed by adjusting the angular positions of the two movable guide smooth elements, so that the processing quality of the inner surface of the pipe wall is influenced decisively, the jig can perform fine processing treatment on the inner surfaces of the pipe fittings with extremely high surface quality, such as a hydraulic cylinder, a vortex tube and the like, and has high processing efficiency and processing quality.
Description
Technical Field
The invention relates to the field of jig dies, in particular to a jig for performing finish machining on the inner surface of a pipe fitting.
Background
In the machining of pipe inner walls where high demands are made on surface accuracy and roughness, the most common method is Surface Plastic Deformation (SPD), which is usually performed under rolling friction, a process commonly referred to as "polishing". The most commonly used tools at present consist of two tools on one body for two-stage machining of cutting and rolling friction, which results in relatively low productivity, and currently in the living practice, there are no machining tools for achieving smooth processing by sliding friction operation. Therefore, in order to meet the current situation, it is urgently needed to develop a jig for finishing the inner surface of the pipe fitting so as to meet the requirement of practical use.
Disclosure of Invention
Accordingly, in view of the disadvantages in the related art, examples of the present invention are provided to substantially solve one or more problems due to limitations and disadvantages of the related art, to substantially improve safety and reliability, and to effectively protect equipment.
According to the technical scheme provided by the invention, the jig for finely machining the inner surface of the pipe fitting comprises a cylindrical main body, the end part of the cylindrical main body is a cylindrical or conical step, three guide smooth elements are arranged on the step, one guide smooth element is fixed on the step, the other two guide smooth elements can move relative to the fixed guide smooth element by utilizing a channel formed on the step, in operation, the three guide smooth elements act on the inner surface of the pipe fitting through sliding friction, and coolant fluid is supplied through a central channel of the cylindrical main body or a gap between the cylindrical main body and the inner surface of the pipe fitting.
Furthermore, the three guiding smooth elements are all made of metal ceramics and are all in incomplete cylindrical shapes, the inner bottom surfaces of the three guiding smooth elements are formed by two areas formed by cylindrical buses coincident with the outer surfaces of the steps, the end parts of the outer surfaces of the three guiding smooth elements are provided with conical parts to form cutting edges, and the three guiding smooth elements are provided with two connecting holes.
Furthermore, two through holes are formed in the step, the connecting piece penetrates through the connecting hole in the fixed guide smooth element and the through hole in the step to be connected with the first connecting plate, and the first connecting plate is located on the inner side of the step.
Furthermore, the channels are 2 groups, namely an upper group channel and a lower group channel, wherein the upper group channel is not communicated with the lower group channel, the upper group channel and the lower group channel are respectively composed of 2 groups of sliding grooves, the connecting piece respectively penetrates through a connecting hole on the moving guide smooth element and a sliding groove on the step to be connected with a second connecting plate, the second connecting plate is positioned on the inner side of the step, and the second connecting plate is composed of a flat plate part and a side plate part.
Further, each guiding smoothing element has a plurality of different size categories, and by replacing guiding smoothing elements of different sizes, finishing of the inner surface of pipe elements of different diameters and lengths can be achieved.
Further, the angle between the center line of the fixed guiding smoothing element and the horizontal line is delta1=45°。
Furthermore, the included angles between the central lines of the two movable guiding smooth elements and the horizontal line are respectively delta2、δ3Angle delta2、δ3The measurement and adjustment is performed by an optical goniometer.
The jig comprises three guide smooth elements, wherein two guide smooth elements can move, when in operation, the three guide smooth elements act on the inner surface of the pipe through sliding friction, and the smooth force generated by the two movable guide smooth elements can be changed by adjusting the angular positions of the two movable guide smooth elements, so that the machining quality of the inner surface of the pipe wall is influenced decisively.
Drawings
FIG. 1 is a schematic view of the present invention.
Fig. 2 is a schematic view of the structural connection of the present invention.
Fig. 3 is a schematic structural side view of the present invention.
Detailed Description
The present invention will be further described with reference to the following specific examples.
The present invention will be described in detail below with reference to specific embodiments shown in the drawings. These embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present invention. The application of the principles of the present invention will be further described with reference to the accompanying drawings and specific embodiments.
The invention relates to an adjustable processing jig which is used for smoothing the inner surface of a pipe fitting by operating three guide smoothing elements through a sliding friction method. To achieve this aim, the device for finishing the inner surface of a tubular element comprises a cylindrical body 1, the cylindrical body 1 being a thick tubular wall on which a stepped portion is machined, in particular the end of the cylindrical body 1 ending with a cylindrical or conical step 2, on which three guiding and smoothing elements are mounted.
Wherein one guiding smoothing element is fixed on the step 2 and the other two guiding smoothing elements are movable with respect to the fixed guiding smoothing element by means of a channel formed on the step 2, and wherein, in operation, the three guiding smoothing elements act on the inner surface of the pipe by means of sliding friction, thereby smoothing.
The coolant fluid is supplied through the central passage of the cylindrical body 1 or through the gap between the cylindrical body 1 and the inner surface of the pipe, so that the high pressure treatment is not additionally required.
The three smooth components of direction are all made by cermet, and the smooth component of three direction is incomplete cylinder shape, and the interior bottom surface of the smooth component of three direction is formed by the region that two cylinder generating lines that coincide with step 2 surface are constituteed, in order to can realize the finish machining to the pipe fitting internal surface of different diameters and length, every smooth component of direction has a plurality of not unidimensional, different materials, through changing the smooth component of different directions and realize above-mentioned purpose.
Two connecting holes are formed in each of the three guiding smooth elements, two through holes are formed in the step 2 for fixing the guiding smooth element 3, the connecting piece penetrates through the connecting holes in the fixing guiding smooth element 3 and the through holes in the step 2 to be connected with the first connecting plate 5, and the first connecting plate 5 is located on the inner side of the step 2; for the movable guiding smooth element 6, the channels are 2 groups and are respectively an upper group of channels and a lower group of channels which are not communicated, the upper group of channels and the lower group of channels are composed of 2 groups of sliding grooves, the connecting pieces respectively penetrate through the connecting holes on the movable guiding smooth element 6 and the sliding grooves on the steps 2 to be connected with the second connecting plate 7, the second connecting plate 7 is positioned on the inner side of the steps 2, and the second connecting plate 7 is composed of a flat plate part and a side plate part.
The end portions of the outer surfaces of the three guide smoothing members each have a tapered portion to form a cutting edge, which facilitates guiding into the pipe member and also allows cutting treatment of fine irregularities on the inner surface of the pipe member.
In fact, the nature of the jig that is capable of machining the internal surface of the pipe is that the three guiding smooth elements are capable of generating a smoothing force on the pipe wall, which is a result of the sliding friction. For the purposes of the present application, the angle between the center line of the stationary guide smoothing element 3 and the horizontal is δ1=45 °, the angles between the center lines of the two movable guiding smoothing elements 6 and the horizontal are each δ2、δ3By adjusting two movable guide platesThe angular position of the slide elements makes it possible to vary the smoothing force generated by the two mobile guiding smoothing elements, which in turn has a decisive influence on the quality of the machining of the inner surface of the tube wall, the variation of the central angle of mutual positioning of the two mobile guiding smoothing elements being achieved by means of the two sets of runners on the step 2.
The use steps of the jig for finely machining the inner surface of the pipe fitting are as follows:
A) selecting a guiding smooth element with a proper size according to the condition of the pipe fitting to be processed;
B) installing a fixed guide smooth element, and respectively penetrating through a connecting hole on the fixed guide smooth element and a through hole on the step by using two bolts and connecting the fixed guide smooth element with the first connecting plate so as to install the fixed guide smooth element on the step;
C) installing a movable guiding smooth element, adjusting an included angle between the central lines of the two movable guiding smooth elements and a horizontal line by using an optical goniometer according to the loading requirement of the friction force on the inner wall of the pipe fitting in the contact area, and then respectively penetrating through a connecting hole on the movable guiding smooth element and a sliding groove on the step by using two bolts to be connected with a second connecting plate, so that the movable guiding smooth element is installed on the step;
D) the jig is inserted into a pipe cavity of the pipe to perform finish machining operation on the inner wall of the pipe, the operation mode adopts one of the modes of a and b, wherein the modes of a, the rotation and the linear motion of the jig and the modes of b, the rotation and the linear motion of the pipe and the jig are adopted, and in the finish machining operation process, a coolant and a lubricant fluid are supplied through a central channel of the cylindrical main body or through a gap between the cylindrical main body and the inner surface of the pipe;
E) and D, repeating the step D for 3-4 times to finish the finish machining of the inner surface of the pipe fitting.
Then, in order to obtain an optimum machining accuracy, an optimum smoothing force, and thus an optimum value of the center rotation angle of the shift guide smoothing element, is necessarily required. For the jig of the present application, the smoothing force acting on the stationary guide smoothing element 3 is F1Acting on the first movement-guiding smoothing element 6 (located in the position ofUpper part of fig. 1) smoothing force F2A smoothing force F acting on the second movement guide smoothing element 6 (located at the lower part of FIG. 1)3Then:
where μ is the coefficient of friction of the guiding smoothing element against the inner wall of the pipe, r is the radius of the cylindrical body 1, MBIs the torque to which the cylindrical body 1 is subjected.
Tables 1-4 present the numerical results when the inner wall of the tube of Q345 steel is finished, the rotating speed of the jig is 45min-1 and the linear feed speed is 0.2mm/rev, and the friction coefficient of the guiding smoothing element against the inner wall of the tube is μ =0.25, where F1=1500N, M =30n.m, which can be measured by a dynamometer, a torque sensor. The negative sign is due to the positioning of the guide smoothing element in the preselected coordinate system.
Table 1F when r =0.025m2、F3 As a function of angle.
Table 2 when r =0.03m, F2、F3 As a function of angle.
Table 3 when r =0.035m, F2、F3 As a function of angle.
Table 4 when r =0.04m, F2、F3 As a function of angle.
As is apparent from the above chart, F2、F3Is dependent on delta2、δ3Increase and decrease; when r increases, F2、F3And also decreases as r increases.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (8)
1. A jig for finely machining the inner surface of a pipe fitting comprises a cylindrical main body (1), wherein the end part of the cylindrical main body (1) is a cylindrical step (2), it is characterized in that three guiding smooth elements are arranged on the step (2), wherein one guiding smooth element is fixed on the step (2), the other two guiding smooth elements can move along the circumferential direction of the step (2) relative to the fixed guiding smooth elements by utilizing the channel formed on the step (2), three of said guiding smoothing elements act on the inner surface of said pipe by sliding friction, the coolant fluid being fed through the central passage of said cylindrical body (1) or through the gap between said cylindrical body (1) and said inner surface of said pipe.
2. A jig for performing fine machining on the inner surface of a pipe fitting according to claim 1, wherein each of the three guide smoothing elements is made of cermet, each of the three guide smoothing elements is in the shape of an incomplete cylinder, the inner bottom surfaces of the three guide smoothing elements are formed by two regions formed by cylindrical generatrices coinciding with the outer surface of the step (2), the end portions of the outer surfaces of the three guide smoothing elements are provided with tapered portions to form cutting edges, and each of the three guide smoothing elements is provided with two connecting holes.
3. A tool for finishing the inner surface of a pipe fitting according to claim 1, wherein said step (2) is provided with two through holes, the connecting member passes through the connecting hole of said fixed guiding smoothing member (3) and the through hole of said step (2) to connect with the first connecting plate (5), said first connecting plate (5) is located inside said step (2).
4. A tool for finishing inner surfaces of pipe fittings according to claim 1, wherein said passages are 2 groups, each of which is an upper group of passages and a lower group of passages, said upper group of passages and said lower group of passages are not communicated, said upper group of passages and said lower group of passages are each composed of 2 groups of sliding grooves, said connecting members are connected with a second connecting plate (7) through said connecting holes of said moving guide smoothing member (6) and said sliding grooves of said step (2), said second connecting plate (7) is located inside said step (2), and said second connecting plate (7) is composed of a flat plate portion and a side plate portion.
5. A jig for finishing the inner surface of pipe fittings as claimed in claim 1 wherein each of said guiding smoothing elements has a plurality of different size categories, and finishing of the inner surface of pipe fittings of different diameters and lengths can be achieved by replacing guiding smoothing elements of different sizes.
6. A tool for finishing the internal surface of pipes according to claim 1, characterized in that the central line of the stationary guiding smoothing element (3) is at an angle δ with the horizontal line1=45°。
7. A tool for finishing the internal surface of pipes according to claim 1, characterized in that the angles between the central line of the two mobile guiding smoothing elements (6) and the horizontal line are respectively δ2、δ3Said angle delta2、δ3The measurement and adjustment is performed by an optical goniometer.
8. A process for finishing the inner surface of a pipe fitting, wherein the process for finishing is completed by a jig for finishing the inner surface of the pipe fitting according to any one of claims 1 to 7, and the process for finishing the inner surface of the pipe fitting is characterized by comprising the following steps:
A) selecting a guiding smooth element with a proper size according to the condition of the pipe fitting to be processed;
B) installing a fixed guide smooth element, and respectively penetrating through a connecting hole on the fixed guide smooth element and a through hole on the step by using two bolts and connecting the fixed guide smooth element with the first connecting plate so as to install the fixed guide smooth element on the step;
C) installing a movable guiding smooth element, adjusting an included angle between the central lines of the two movable guiding smooth elements and a horizontal line by using an optical goniometer according to the loading requirement of the friction force on the inner wall of the pipe fitting in the contact area, and then respectively penetrating through a connecting hole on the movable guiding smooth element and a sliding groove on the step by using two bolts to be connected with a second connecting plate, so that the movable guiding smooth element is installed on the step;
D) the method comprises the following steps that a, a jig rotates and moves linearly, b, the pipe rotates and moves linearly, and coolant and lubricant fluid are supplied to a central channel of a cylindrical main body or a gap between the cylindrical main body and the inner surface of the pipe fitting in the finish machining operation process;
E) and D, repeating the step D for 3-4 times to finish the finish machining of the inner surface of the pipe fitting.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910372909.2A CN109955156B (en) | 2019-05-06 | 2019-05-06 | Tool for finely machining inner surface of pipe fitting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910372909.2A CN109955156B (en) | 2019-05-06 | 2019-05-06 | Tool for finely machining inner surface of pipe fitting |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109955156A CN109955156A (en) | 2019-07-02 |
| CN109955156B true CN109955156B (en) | 2019-12-31 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201910372909.2A Expired - Fee Related CN109955156B (en) | 2019-05-06 | 2019-05-06 | Tool for finely machining inner surface of pipe fitting |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201940903U (en) * | 2010-11-15 | 2011-08-24 | 朱菊香 | Grinding wheel for casting finishing |
| CN105479308A (en) * | 2015-12-07 | 2016-04-13 | 大连金河铸造有限公司 | Device for grinding inner wall of hole |
| CN106736924A (en) * | 2016-12-27 | 2017-05-31 | 重庆优萃科技有限公司 | A kind of endoporus grinding apparatus and its polishing process |
| DE102015225803A1 (en) * | 2015-12-17 | 2017-06-22 | Kadia Produktion Gmbh + Co. | honing tool |
| CN108406459A (en) * | 2018-03-07 | 2018-08-17 | 广东派博钢管有限公司 | Steel pipe inside and outside integrative automatic grinding system |
| CN208451215U (en) * | 2018-07-20 | 2019-02-01 | 株洲时代新材料科技股份有限公司 | A kind of shaft end portion grinding fixture |
| CN208729484U (en) * | 2018-07-27 | 2019-04-12 | 常州凯瑞莱精密工具有限公司 | A kind of hone |
-
2019
- 2019-05-06 CN CN201910372909.2A patent/CN109955156B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201940903U (en) * | 2010-11-15 | 2011-08-24 | 朱菊香 | Grinding wheel for casting finishing |
| CN105479308A (en) * | 2015-12-07 | 2016-04-13 | 大连金河铸造有限公司 | Device for grinding inner wall of hole |
| DE102015225803A1 (en) * | 2015-12-17 | 2017-06-22 | Kadia Produktion Gmbh + Co. | honing tool |
| CN106736924A (en) * | 2016-12-27 | 2017-05-31 | 重庆优萃科技有限公司 | A kind of endoporus grinding apparatus and its polishing process |
| CN108406459A (en) * | 2018-03-07 | 2018-08-17 | 广东派博钢管有限公司 | Steel pipe inside and outside integrative automatic grinding system |
| CN208451215U (en) * | 2018-07-20 | 2019-02-01 | 株洲时代新材料科技股份有限公司 | A kind of shaft end portion grinding fixture |
| CN208729484U (en) * | 2018-07-27 | 2019-04-12 | 常州凯瑞莱精密工具有限公司 | A kind of hone |
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| Publication number | Publication date |
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| CN109955156A (en) | 2019-07-02 |
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Effective date of registration: 20191204 Address after: 276800 Zhufu Industrial Park, Lanshan District, Rizhao City, Shandong Province Applicant after: Rizhao Zhufu Industry Co., Ltd Address before: 215163 Room 601, 7 building, 78 Ling Ling Road, hi tech Zone, Suzhou, Jiangsu. Applicant before: Suzhou Chen Sheng Mechanical and Electrical Technology Co., Ltd. |
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