CN110842465B - Repairing process of shaft sleeve for support of rim roll forming machine - Google Patents
Repairing process of shaft sleeve for support of rim roll forming machine Download PDFInfo
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- CN110842465B CN110842465B CN201911053599.4A CN201911053599A CN110842465B CN 110842465 B CN110842465 B CN 110842465B CN 201911053599 A CN201911053599 A CN 201911053599A CN 110842465 B CN110842465 B CN 110842465B
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- shaft sleeve
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- surfacing
- wall
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P6/00—Restoring or reconditioning objects
Abstract
The invention provides a repairing process of a shaft sleeve for a support of a rim roll forming machine, which comprises the following steps of: step S1, equally dividing the area A and the area B into X small fan-shaped areas by taking the shaft sleeve axis as the center, and equally dividing the area C and the area D into Y small fan-shaped areas by taking the shaft sleeve axis as the center; step S2, insulating the outer peripheral wall of the shaft sleeve by an insulating layer; step S3, performing surfacing repair on the inner peripheral wall of the shaft sleeve by welding rods in a cold welding mode; firstly, performing surfacing repair on the shaft sleeves in the area A and the area B, then performing surfacing repair on the shaft sleeve in the area D, and finally performing surfacing repair on the shaft sleeve in the area C; and step S4, fixing the overlaid shaft sleeve on a boring machine, and machining the through hole of the shaft sleeve to a calibrated diameter by using the boring machine. The invention can carry out surfacing repair on the inner wall of the shaft sleeve by adopting a partition surfacing and symmetrical surfacing mode, and can ensure that the thinner part of the wall thickness of the shaft sleeve does not crack.
Description
Technical Field
The invention relates to the technical field of tool repair, in particular to a repair process of a shaft sleeve for a support of a rim roll forming machine.
Background
Along with the increasingly deepened concept of cost reduction and efficiency improvement, waste equipment is reused as one of cost reduction and efficiency improvement measures, and meanwhile, improvement of the technological process and improvement of maintenance efficiency are urgent matters of maintenance units. The bearing of the rim roll forming machine in Bao steel wheel factories is imported cast iron, after 2-3 years of use, the repeated friction between the shaft sleeve and the bearing causes the abrasion of the shaft sleeve, the abrasion depth reaches about 1mm, the equipment can not be used, the repair process is not found in domestic data, and the new bearing is generally replaced. If the support is repaired, the following difficulties exist:
1. the pedestal is imported equipment, chemical components of cast iron are different from chemical components in China, if a conventional cast iron welding method is adopted, a cast iron welding rod can be selected, the cast iron welding rod has poor welding process performance, a welding seam is not formed, all air holes and cracks are mixed on the welding seam, and the same welding problems exist in hot welding and semi-prehot welding (several processes are tested when the cast iron welding rod is adopted for welding).
2. The radial thickness of one side of the shaft sleeve of the device is very thin, the radial thicknesses of other sides are very thick, the thickness difference of one circumference is too large, and if the inner circle is welded for a circle, the stress of the thick side can be released at the thin side, so that the thin side is cracked, and the welding failure is caused.
3. This equipment is bulky, and this equipment if adopt the part to preheat, will increase the stress of component, leads to the appearance of welding crack, if adopt whole preheating, just needs great preheating device, need follow the oven after preheating and transfer out and just can weld, and the back is fallen in the temperature, has to send back the oven and heats, so heats repeatedly and leads to the inside stress increase of cast iron with the cooling to it is the welding failure.
4. The welded welding surface needs to be subjected to finish machining, and a concentric axis between the two shaft sleeves is difficult to find during machining.
5. The workpiece is a stressed part, the hardness of the contact surface of the original shaft sleeve is 160-210HBS, and the hardness of the welding surface is less than the value, so that the service life and the use precision are seriously shortened. If the hardness is too high, the welding surface can not be processed after the components are welded.
Disclosure of Invention
In view of the above drawbacks of the prior art, the technical problem to be solved by the present invention is to provide a repair process for a shaft sleeve for a support of a rim roll forming machine, in which a partition surfacing and symmetric surfacing method is adopted to repair an inner peripheral wall of the shaft sleeve, so as to ensure that a thin wall of the shaft sleeve does not crack, and the shaft sleeve after the surfacing repair can be put into use again, thereby saving equipment purchase cost.
In order to solve the technical problem, the invention provides a repairing process of a shaft sleeve for a rim roll forming machine support, wherein the outer peripheral wall of the shaft sleeve is composed of a plane outer wall and a curved outer wall, a sector area corresponding to the plane outer wall is defined as a C area, a sector area symmetrical to the C area in the curved outer wall is defined as a D area, and two sector areas corresponding to the rest part of the curved outer wall are respectively defined as an A area and a B area, the repairing process comprises the following steps:
step S1, equally dividing the area A and the area B into X small fan-shaped areas by taking the shaft sleeve axis as the center, and recording the small fan-shaped areas A1-AX and B1-BX, wherein the Ai small fan-shaped areas and the Bi small fan-shaped areas are symmetrically arranged by taking the shaft sleeve axis as the center and form a pair of fan-shaped groups; equally dividing the region C and the region D into Y small fan-shaped regions by taking the shaft sleeve axis as the center, and marking as the small fan-shaped regions C1-CY and the small fan-shaped regions D1-DY;
step S2, insulating the outer peripheral wall of the shaft sleeve by an insulating layer;
step S3, performing surfacing repair on the inner peripheral wall of the shaft sleeve by welding rods in a cold welding mode; firstly, performing surfacing repair on the shaft sleeves in the area A and the area B, then performing surfacing repair on the shaft sleeve in the area D, and finally performing surfacing repair on the shaft sleeve in the area C; when the inner peripheral walls of the shaft sleeves in the area A and the area B are subjected to surfacing repair, the inner peripheral walls of the shaft sleeves in different fan-shaped groups are subjected to surfacing repair in sequence from the middle of the area A and the area B to the side edges of the area A and the area B; when the inner peripheral wall of the shaft sleeve in the D area is subjected to surfacing repair, firstly, the inner peripheral wall of the shaft sleeve in the small fan-shaped areas distributed at intervals is subjected to surfacing repair, and then, the inner peripheral wall of the shaft sleeve in the residual small fan-shaped areas is subjected to surfacing repair; when the inner peripheral wall of the shaft sleeve in the C area is subjected to surfacing repair, the inner peripheral walls of the shaft sleeve in different small sector areas are subjected to surfacing repair according to the sequence from the side edge of the C area to the middle of the C area.
And step S4, fixing the overlaid shaft sleeve on a boring machine, and machining the through hole of the shaft sleeve to a calibrated diameter by using the boring machine.
Preferably, in step S4, the two sleeves are repaired by overlay welding according to steps S1 to S3, the two overlaid sleeves are simultaneously fixed on a boring machine, and the through holes of the two sleeves are machined to the calibrated concentricity by the boring machine.
Preferably, in step S3, the electrode has a diameter of 3.2 mm.
Preferably, in step S3, the current used in the cold welding method is 100 to 110A.
Preferably, in step S2, the heat insulating layer is made of a cotton material.
Preferably, in step S3, the electrode is ENiCrMo-3.
Preferably, in step S3, during the process of performing the bead welding repair on the inner peripheral wall of the sleeve, when the temperature of the welding position exceeds 150 ℃, the bead welding is stopped; when the temperature of the welding position is lower than 100 ℃, the surfacing is continued.
As mentioned above, the repair process of the shaft sleeve for the support of the rim roll forming machine has the following beneficial effects: in the repairing process of the shaft sleeve for the rim roll forming machine support, the wall thickness of the shaft sleeve in the C area is thin, and the wall thickness of the shaft sleeve in the A area, the B area and the D area is thick. According to the repairing process, the inner wall of the shaft sleeve is subjected to surfacing repair in a partition surfacing and symmetrical surfacing mode, so that the thin wall of the shaft sleeve is prevented from cracking, the shaft sleeve after surfacing repair can be put into use again, and the equipment purchase cost is saved.
Drawings
FIG. 1 is a schematic view of a bushing for a rim roll forming machine support of the present invention;
FIG. 2 shows a schematic of the rim roll machine stand of the present invention.
Description of the element reference numerals
1 axle sleeve
11 plane outer wall
12 curved outer wall
2 wheel rim roll forming machine support
21 shaft sleeve mounting position
Detailed Description
The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.
It should be understood that the structures, ratios, sizes, and the like shown in the drawings are only used for matching the disclosure of the present disclosure, and are not used for limiting the conditions that the present disclosure can be implemented, so that the present disclosure is not limited to the technical essence, and any structural modifications, ratio changes, or size adjustments should still fall within the scope of the present disclosure without affecting the efficacy and the achievable purpose of the present disclosure. In addition, the terms "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for clarity of description, and are not intended to limit the scope of the present invention, and the relative relationship between the terms and the terms is not to be construed as a scope of the present invention.
As shown in fig. 1 and 2, the present invention provides a repairing process of a shaft sleeve for a rim roll forming machine support, wherein an outer peripheral wall of the shaft sleeve 1 is composed of a plane outer wall 11 and a curved outer wall 12, a sector area corresponding to the plane outer wall 11 is defined as a C area, a sector area symmetrical to the C area in the curved outer wall 12 is defined as a D area, and two sector areas corresponding to the remaining portion of the curved outer wall 12 are respectively defined as an a area and a B area, the repairing process includes the following steps:
step S1, equally dividing the area A and the area B into X small fan-shaped areas by taking the shaft sleeve axis as the center, and recording the small fan-shaped areas A1-AX and B1-BX, wherein the Ai small fan-shaped areas and the Bi small fan-shaped areas are symmetrically arranged by taking the shaft sleeve axis as the center and form a pair of fan-shaped groups; equally dividing the region C and the region D into Y small fan-shaped regions by taking the shaft sleeve axis as the center, and marking as the small fan-shaped regions C1-CY and the small fan-shaped regions D1-DY;
step S2, insulating the outer peripheral wall of the shaft sleeve 1 by a heat-insulating layer to ensure that the temperature of the shaft sleeve 1 is slowly reduced during surfacing;
step S3, performing surfacing repair on the inner peripheral wall of the shaft sleeve 1 by welding rods in a cold welding mode; firstly, performing surfacing repair on the shaft sleeve 1 in the area A and the area B, then performing surfacing repair on the shaft sleeve 1 in the area D, and finally performing surfacing repair on the shaft sleeve 1 in the area C; when the inner circumferential walls of the shaft sleeve 1 in the area A and the area B are subjected to surfacing repair, the inner circumferential walls of the shaft sleeve 1 in different fan-shaped groups are subjected to surfacing repair in sequence from the middle of the area A and the area B to the side edges of the area A and the area B; when the inner peripheral wall of the shaft sleeve 1 in the D area is subjected to surfacing repair, firstly, the inner peripheral wall of the shaft sleeve 1 in the small sector areas distributed at intervals is subjected to surfacing repair, and then, the inner peripheral wall of the shaft sleeve 1 in the rest small sector areas is subjected to surfacing repair; when the inner peripheral wall of the shaft sleeve 1 in the C area is subjected to surfacing repair, the inner peripheral walls of the shaft sleeve 1 in different small sector areas are subjected to surfacing repair according to the sequence from the side edge of the C area to the middle of the C area.
And step S4, fixing the overlaid shaft sleeve 1 on a boring machine, and machining the through hole of the shaft sleeve 1 to a calibrated diameter by using the boring machine.
In the repairing process of the sleeve for the rim roll stand according to the present invention, the thickness of the sleeve 1 located in the region C is thin (generally, the minimum thickness of the sleeve 1 located in the region C is 3 mm), and the thickness of the sleeve 1 located in the regions a, B, and D is thick (generally, the thickness of the sleeve 1 located in the regions a, B, and D is 30 mm). If the traditional surfacing repair method is adopted, namely the surfacing is continuously performed for one circle on the inner peripheral wall of the shaft sleeve 1 according to the clockwise or anticlockwise sequence, the thinner part of the wall thickness of the shaft sleeve 1 is easy to crack. According to the repairing process, the inner circumferential wall of the shaft sleeve 1 is subjected to surfacing repair in a partition surfacing and symmetrical surfacing mode, so that a thinner part of the wall thickness of the shaft sleeve 1 can be prevented from cracking, the shaft sleeve 1 after surfacing repair is finished can be put into use again, and the equipment purchase cost is saved.
As an example of the repair process of the sleeve for the rim roll forming machine stand as described above, as shown in fig. 1: in step S1, equally dividing each of the a region and the B region into 5 small fan-shaped regions centered on the sleeve axis, and as a1 to a5 small fan-shaped regions and B1 to B5 small fan-shaped regions, the Ai small fan-shaped regions and the Bi small fan-shaped regions are symmetrically arranged centered on the sleeve axis and constitute a pair of fan-shaped groups; the region C and the region D were each divided equally into 4 small sectorial regions centered on the sleeve axis, and recorded as C1 to C4 small sectorial regions and D1 to D4 small sectorial regions. Firstly, performing surfacing repair on the shaft sleeve 1 positioned in the area A and the area B, wherein the surfacing sequence is as follows: b3, A3, B2, a2, B4, a4, B5, a5, B1, and a 1. Then, carrying out surfacing repair on the shaft sleeve 1 positioned in the D area, wherein the surfacing sequence is as follows: d1, D3, D2 and D4. And finally, performing surfacing repair on the shaft sleeve 1 positioned in the C area, wherein the surfacing sequence is as follows: c4, C1, C2 and C3.
Further, in step S4, the two shaft sleeves 1 are subjected to overlay welding repair according to steps S1 to S3, the two overlaid shaft sleeves 1 are simultaneously fixed on a boring machine, and the through holes of the two shaft sleeves 1 are machined to the calibrated concentricity by the boring machine. Specifically, as shown in fig. 2, the rim roll forming machine support 2 has two sleeve mounting positions, and after two sleeve 1 processed by a boring machine are respectively assembled at the corresponding sleeve mounting positions 21, the concentricity of the two sleeve 1 conforms to the calibrated concentricity.
In step S3, the electrode has a diameter of 3.2mm, which can reduce the heat input.
In step S3, the current used in the cold welding method is 100-110A.
In step S2, the insulating layer is made of a cotton material.
In step S3, since the support of the rim roll forming machine is made of iron, if the welding rod is made of cast iron, the welding process is poor, the weld is not formed, and the weld has pores and cracks. If the type of the welding rod is ENiCrMo-3, the welding rod has good process performance, the hardness after welding can reach 220-304 HBS, which is higher than that of the shaft sleeve 1, the wear resistance of the shaft sleeve 1 is improved, and the service life of the shaft sleeve 1 is prolonged.
In step S3, in the process of performing weld deposit repair on the inner circumferential wall of the sleeve 1, when the temperature of the weld exceeds 150 ℃, the weld deposit is stopped; when the temperature of the welding position is lower than 100 ℃, the surfacing is continued; in this way, a small thermal stress can be secured in the sleeve 1.
In conclusion, the repair process disclosed by the invention adopts the modes of zone surfacing and symmetrical surfacing to perform surfacing repair on the inner peripheral wall of the shaft sleeve, so that the thinner part of the wall thickness of the shaft sleeve can be prevented from cracking, the shaft sleeve after surfacing repair can be put into use again, and the equipment purchase cost is saved. Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (6)
1. The repair process of the shaft sleeve for the rim roll forming machine support is characterized in that the outer peripheral wall of the shaft sleeve (1) is composed of a plane outer wall (11) and a curved outer wall (12), a sector area corresponding to the plane outer wall (11) is defined as an area C, a sector area symmetrical to the area C in the curved outer wall (12) is defined as an area D, two sector areas corresponding to the rest part of the curved outer wall (12) are respectively defined as an area A and an area B, the wall thickness of the shaft sleeve (1) located in the area C is thin, the wall thickness of the shaft sleeve (1) located in the area A, the area B and the area D is thick, and the rim roll forming machine support is a cast iron part not suitable for cast iron welding rods;
the repair process comprises the following steps:
step S1, equally dividing the area A and the area B into X small fan-shaped areas by taking the shaft sleeve axis as the center, and recording the areas as A1～AXSmall sector area and B1～BXSmall sector area, AiSmall sector area and BiThe small fan-shaped areas are symmetrically arranged by taking the shaft sleeve axis as the center and form a pair of fan-shaped groups; the C area and the D area are equally divided into Y small fan-shaped areas by taking the shaft sleeve axis as the center and are marked as C1～CYSmall sector area and D1～DYA small sector area;
step S2, insulating the outer peripheral wall of the shaft sleeve (1) by an insulating layer;
s3, performing surfacing repair on the inner peripheral wall of the shaft sleeve (1) in a cold welding mode through a welding rod with the type of ENiCrMo-3; firstly, performing surfacing repair on the shaft sleeves (1) in the area A and the area B, then performing surfacing repair on the shaft sleeve (1) in the area D, and finally performing surfacing repair on the shaft sleeve (1) in the area C; when the inner circumferential walls of the shaft sleeves (1) in the areas A and B are subjected to surfacing repair, the inner circumferential walls of the shaft sleeves (1) in different fan-shaped groups are subjected to surfacing repair in sequence from the middle of the areas A and B to the side edges of the areas A and B; when the inner peripheral wall of the shaft sleeve (1) in the D area is subjected to surfacing repair, firstly, the inner peripheral wall of the shaft sleeve (1) in the small fan-shaped areas distributed at intervals is subjected to surfacing repair, and then, the inner peripheral wall of the shaft sleeve (1) in the residual small fan-shaped areas is subjected to surfacing repair; when the inner circumferential wall of the shaft sleeve (1) positioned in the C area is subjected to surfacing repair, the inner circumferential wall of the shaft sleeve (1) positioned in different small sector areas is subjected to surfacing repair according to the sequence from the side edge of the C area to the middle of the C area;
and step S4, fixing the overlaid shaft sleeve (1) on a boring machine, and machining the through hole of the shaft sleeve (1) to a calibrated diameter by using the boring machine.
2. The repair process of the shaft sleeve for the support of the rim roll forming machine according to claim 1, characterized in that: in step S4, the two shaft sleeves (1) are subjected to surfacing repair according to the steps S1-S3, the two shaft sleeves (1) subjected to surfacing are simultaneously fixed on a boring machine, and through holes of the two shaft sleeves (1) are machined to the calibrated concentricity by the boring machine.
3. The repair process of the shaft sleeve for the support of the rim roll forming machine according to claim 1, characterized in that: in step S3, the electrode diameter is 3.2 mm.
4. The repair process of the shaft sleeve for the support of the rim roll forming machine according to claim 1, characterized in that: in step S3, the current used in the cold welding method is 100-110A.
5. The repair process of the shaft sleeve for the support of the rim roll forming machine according to claim 1, characterized in that: in step S2, the insulating layer is made of a cotton material.
6. The repair process of the shaft sleeve for the support of the rim roll forming machine according to claim 1, characterized in that: in step S3, in the process of carrying out overlay welding repair on the inner peripheral wall of the shaft sleeve (1), when the temperature of a welding part exceeds 150 ℃, the overlay welding is stopped; when the temperature of the welding position is lower than 100 ℃, the surfacing is continued.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911053599.4A CN110842465B (en) | 2019-10-31 | 2019-10-31 | Repairing process of shaft sleeve for support of rim roll forming machine |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911053599.4A CN110842465B (en) | 2019-10-31 | 2019-10-31 | Repairing process of shaft sleeve for support of rim roll forming machine |
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| CN110842465A CN110842465A (en) | 2020-02-28 |
| CN110842465B true CN110842465B (en) | 2021-07-13 |
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| CN113976927A (en) * | 2021-10-27 | 2022-01-28 | 三门核电有限公司 | Repair method for triple eccentric butterfly valve |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102284826A (en) * | 2011-08-09 | 2011-12-21 | 东芝水电设备（杭州）有限公司 | Repair process for cavitation corrosion of runner chamber of through-flow type water turbine |
| CN103658931A (en) * | 2013-12-30 | 2014-03-26 | 太原重工轨道交通设备有限公司 | Double-layer bead welding method for axle swage block |
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- 2019-10-31 CN CN201911053599.4A patent/CN110842465B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102284826A (en) * | 2011-08-09 | 2011-12-21 | 东芝水电设备（杭州）有限公司 | Repair process for cavitation corrosion of runner chamber of through-flow type water turbine |
| CN103658931A (en) * | 2013-12-30 | 2014-03-26 | 太原重工轨道交通设备有限公司 | Double-layer bead welding method for axle swage block |
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