CN114689001B - Press centering test method - Google Patents
Press centering test method Download PDFInfo
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- CN114689001B CN114689001B CN202210364748.4A CN202210364748A CN114689001B CN 114689001 B CN114689001 B CN 114689001B CN 202210364748 A CN202210364748 A CN 202210364748A CN 114689001 B CN114689001 B CN 114689001B
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- pressing plate
- pressure
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- 238000010998 test method Methods 0.000 title claims abstract description 16
- 238000003825 pressing Methods 0.000 claims abstract description 106
- 238000012360 testing method Methods 0.000 claims abstract description 21
- 238000000034 method Methods 0.000 claims abstract description 9
- 230000003068 static effect Effects 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 238000000748 compression moulding Methods 0.000 abstract description 8
- 230000006835 compression Effects 0.000 abstract description 3
- 238000007906 compression Methods 0.000 abstract description 3
- 230000005540 biological transmission Effects 0.000 abstract description 2
- 238000000465 moulding Methods 0.000 abstract description 2
- 238000012805 post-processing Methods 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 239000004484 Briquette Substances 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 229910001128 Sn alloy Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000012778 molding material Substances 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 229910052718 tin Inorganic materials 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Control Of Presses (AREA)
Abstract
The invention discloses a press center searching test method, which is characterized in that the center position of four-column press working pressure transmission can be quickly found through test adjustment of a pressing plate and a pressing block under the static state of a press and the working pressure respectively, namely, the position of the pressure center is found on a press workbench, and then a die is arranged according to the determined press pressure center to carry out compression molding, so that the problem of die unbalanced load is avoided, the compression precision of compression molding is improved, the method can be used for near-net size molding of parts, and post-processing procedures are saved.
Description
Technical Field
The invention belongs to the technical field of powder metallurgy, and particularly relates to a press centering test method.
Background
Hydraulic presses are mechanical devices which transmit pressure through fluid by using pascal principle, and a main body structure is usually pushed by adopting three beams, four columns and a plunger. The device is commonly used for the processing procedures of compression molding, forging and pressing, stamping, plate pressing, press fitting, correction and the like of materials such as metal, plastic, rubber, wood, powder and the like, is high-pressure, efficient, low-carbon and green manufacturing equipment, and is widely applied to various fields of national economy.
The compression molding is to put the molding material into the cavity of the female mold, then to close the male mold, and to squeeze, deform, bite, soften and compress the material to fill the cavity by means of the pressure and heat provided by the press, so as to form the same product as the cavity. However, long-term attention and use have found that four-column presses generally have low pressing accuracy, and are only used for part blank forming, and are not suitable for near-net-size forming with little or no further processing.
In order to improve the forming precision of parts, the patent 201410841510.1 adopts an over-positioning forming technology, improves the parallelism of upper and lower working tables of a press under high pressure, and can be used for pressing small-size (the size of a die is less than 50% relative to the size of the working table of the press); the 202110906225.3 patent solves the centering problem (two-axis concentricity) of the die relative to the four upright posts, but the phenomenon that the pressure center (referred to as the plunger center) is not coaxial with the two centers (the center of the workbench and the center of the four upright posts) (the three axes are not concentric) exists at present, so that the pressure unbalanced load phenomenon easily occurs in the working press, and further the further improvement of the pressing precision is influenced.
In order to avoid the problem of unbalanced load commonly existing in compression molding, the precision national standard GBT9166-2009 of a four-column hydraulic press is inquired, and the requirements of flatness and parallelism of an upper working table surface and a lower working table surface of the press under static state are found out in the press standard of maximum pressure 100T and working table 400mm, and the related position indexes such as flatness and parallelism of the upper working table surface and the lower working table surface under high pressure, parallelism of four guide columns, coaxiality of three shafts and the like are avoided; in addition, there are many methods for determining the center of pressure in engineering (for example, the method for determining the center of pressure of a die based on auto_CAD2000, patent 201010039114.9), but many of these methods are a mapping method, a calculation method, a software analysis method, etc., and have little practical significance. The prior art cannot accurately measure the pressure center position of a four-column press in engineering, and a test method is needed to find the pressure center of the press.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a press centering test method for searching a pressure center of a press in a working state on a workbench, so that the compression precision of compression molding is improved, and the problem of unbalanced load of a die is avoided.
In order to solve the technical problems, the invention adopts the following technical scheme:
a press center finding test method comprises the following steps:
1) Under static state, adjusting parallelism of upper and lower working tables of the press;
2) Measuring and determining the geometric center of a workbench surface on the workbench surface of the press, and marking the geometric center as a point A of the workbench center;
3) Measuring and determining the geometric center of four upright posts on a working table of the press, and marking as a point B of the center of the four upright posts;
4) Taking the center C point of the two points of A, B as a base point on the working table surface of the press, and testing under working pressure;
a. manufacturing two high-precision pressing plates and a plurality of identical pressing blocks;
b. establishing a rectangular coordinate system on a pressing plate plane, respectively placing a pressing block in four quadrants of the pressing plate, wherein the pressing blocks in the four quadrants are uniformly distributed along a concentric circle;
c. placing another pressing plate on the four pressing blocks to form a combined pressing plate, and then placing the combined pressing plate on a working table of a press, wherein the center O of the combined pressing plate coincides with the base point C;
d. pressing according to preset working pressure, and measuring the thickness of the four pressing blocks;
e. judging the direction of the pressure center according to the thickness and the positions of the four pressing blocks:
if the thickness difference of the four pressing blocks does not reach the preset value of the working pressure test of the press, slightly moving the pressing plate to the pressing block position with smaller thickness, repeating the steps b-e again, and performing the next round of test until the thickness difference of the four pressing blocks is not larger than the preset value;
when the thickness difference is not larger than a preset value, the center O position of the combined pressing plate is the pressure center of the press, and is marked;
f. and (5) finishing the work of searching the pressure center of the press.
The diameter of the pressing plate is consistent with the diameter of a die for a product to be produced, the flatness and parallelism of the pressing plate are less than or equal to 0.002mm, and the hardness HRC is more than or equal to 50.
The pressing blocks are arranged corresponding to the pressing machine in direction, and the concentric circles of the pressing blocks are directly consistent with the measured diameter of the product to be produced.
The materials and the specification and the dimensions of the pressing blocks are the same.
The thickness difference of the preset value of the working pressure test of the press is 0-10 mu m.
The thickness difference of the preset value of the working pressure test of the press is 5 mu m.
The beneficial effects of the invention are as follows:
according to the press centering test method, the center position of the four-column press working pressure transmission can be quickly found through test adjustment of the pressing plate and the pressing block under the static state of the press and the working pressure, namely, the position of the pressure center is found on the press workbench, and then the die is set for compression molding according to the determined press pressure center, so that the problem of die unbalanced load is avoided, the compression precision of compression molding is improved, the press centering test method can be used for near-net-size molding of parts, and post-processing procedures are saved.
Drawings
FIG. 1 is a schematic view of a down-press four-column press;
FIG. 2 is a schematic diagram of the present invention;
FIG. 3 is a schematic view of the placement of compacts on a platen;
FIG. 4 is a side view of FIG. 3;
fig. 5 is a schematic diagram of the steps of the present invention.
Detailed Description
Further advantages and effects of the present invention will become apparent to those skilled in the art from the disclosure of the present invention, which is described by the following specific examples.
The invention provides a press centering test method, which is shown in fig. 1 to 5.
The press centering test method comprises the following steps:
1) Under static state, adjusting parallelism of upper and lower working tables of the press;
2) Measuring and determining the geometric center of the working table on the working table of the press, and marking the geometric center as a point A of the working table;
3) Measuring and determining the geometric center of four upright posts on the working table of the press, and marking as a point B of the center of the four upright posts;
4) Taking the center C point of the two points of A, B as a base point on the working table surface of the press, and testing under working pressure;
a. manufacturing two high-precision pressing plates and a plurality of identical pressing blocks;
b. establishing a rectangular coordinate system on a pressing plate plane, respectively placing a pressing block in four quadrants of the pressing plate, wherein the pressing blocks in the four quadrants are uniformly distributed along a concentric circle;
c. placing another pressing plate on the four pressing blocks to form a combined pressing plate, and then placing the combined pressing plate on a working table of a press, wherein the center O of the combined pressing plate coincides with the base point C;
d. pressing according to preset working pressure, and measuring the thickness of the four pressing blocks;
e. judging the direction of the pressure center according to the thickness and the positions of the four pressing blocks:
if the thickness difference of the four pressing blocks does not reach the preset value of the working pressure test of the press, slightly moving the pressing plate to the pressing block position with smaller thickness, repeating the steps b-e again, and performing the next round of test until the thickness difference of the four pressing blocks is not larger than the preset value;
when the thickness difference is not greater than a preset value, the center O position of the combined pressing plate is the pressure center of the press, and is marked;
f. and (5) finishing the work of searching the pressure center of the press.
It should be noted that the diameter of the pressing plate is consistent with the diameter of a die for a product to be produced, the flatness and parallelism of the pressing plate are less than or equal to 0.002mm, and the hardness HRC is more than or equal to 50.
The pressing blocks are arranged corresponding to the pressing machine in direction, the diameter of concentric circles of the pressing blocks is consistent with the measured diameter of a product to be produced, and the material and the dimensional accuracy of the pressing blocks are the same.
The thickness difference of the preset value is tested by the working pressure of the press and is 0-10 mu m, and in the embodiment, the thickness difference of the preset value is tested by the working pressure of the press and is 5 mu m.
The specific technical scheme is as follows:
1) Under static state, the upper beam 5 and the lower beam 1 of the press are adjusted to ensure that the parallelism of the upper workbench 51 and the workbench surface 31 of the lower workbench 3 is less than or equal to 0.05mm and reaches or exceeds the existing national standard of the press;
2) On a working table 31 of the press, measuring and determining the geometric center of the working table 31, and marking as A;
3) On the working table 31 of the press, the geometric center of the four upright posts 4 is measured and determined, and is marked as B;
4) On the working table 31 of the press, the center of A, B is taken as a base point C, and the pressure center of the four-column press is tested and determined under working pressure, and in the embodiment, the press applies pressure to the working table through the oil cylinder 2;
(1) two high-precision pressing plates 6 and a plurality of pressing blocks 7 are manufactured;
(2) a rectangular coordinate system 0xy is established on the plane of a pressing plate 6, pressing blocks 7a, 7b, 7c and 7d are respectively placed in four quadrants of the pressing plate, and the four pressing blocks are uniformly distributed along a concentric circle;
(3) placing another pressing plate 6 on the four pressing blocks 7, and placing the combined pressing plate 6 on a working table 31 of the press so that the center O of the pressing plate 6 coincides with the base point C;
(4) pressing according to a preset working pressure, and measuring the thickness of the four pressing blocks 7;
(5) judging the direction of the pressure center according to the thickness and the positions of the four pressing blocks 7:
in this embodiment, the working pressure of the press is measured to measure the thickness difference of 5 μm, the thickness difference of the four press blocks is measured to be 20 μm, if the thickness difference does not reach the preset value of 5 μm, the press plate 6 is slightly moved to the position of the press block 7a with small thickness by 1mm, then the next round of test is repeated again (2) - (6), the thickness difference of the four press blocks 7 is gradually reduced in sequence, the measured thickness difference is measured to be 4.5 μm, and if the thickness difference is smaller than the preset value of 5 μm, the center position O of the press plate 6 is the pressure center of the press, and the + is marked.
5) And (5) finishing the work of searching the pressure center of the press.
So far, the press centering precision test work is finished; after the pressure center of the press is found, when powder material is precisely pressed, the die center is necessarily arranged at the pressure center of the press for forming, so that the press forming precision is improved, and the problem of unbalanced load of the die is avoided.
The pressing plate 6 is used as a reference for pressure test, the flatness and parallelism of the pressing plate 6 are required to be less than or equal to 0.002mm, the hardness HRC is more than or equal to 50, and the diameters of the two pressing plates 6 are required to be consistent with the diameter of a die to be produced.
It should be noted that, the four pressing blocks 7 are arranged to test the pressure of the corresponding positions of the press, the specific positions of the four pressing blocks must correspond to the directions of the press, and the concentric circle diameter of the layout of the four pressing blocks 7 is consistent with the measured diameter of the product to be produced.
It should be noted that, the pressing block 7 is used for pressure deformation test, and the pressing block 7 material should have a certain deformation resistance; in addition, the four pressing blocks 7 are required to be made of the same material, have the same organization, have the same density, have the same size and have the same precision; the size of the bearing area can be measured and calculated according to the working pressure and the deformation strength of the material; the materials of the briquette 7 are mainly tin and tin alloy, aluminum and aluminum alloy, copper and copper alloy, etc.
It should be noted that the micro-movement can be determined according to the tonnage of the press, the diameter of the die, the anti-unbalanced load condition and the working experience, and the anti-unbalanced load can be cm and mm, and the anti-unbalanced load can be mm and micron.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which are all within the scope of the claimed invention. The scope of the invention is defined by the appended claims and equivalents.
In the description of the present invention, it should be understood that the directions or positional relationships indicated by the terms "front", "rear", "left", "right", "center", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or element to be referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the protection of the present invention.
Claims (6)
1. A press center finding testing method is characterized in that: the method comprises the following steps:
1) Under static state, adjusting parallelism of upper and lower working tables of the press;
2) Measuring and determining the geometric center of a workbench surface on the workbench surface of the press, and marking the geometric center as a point A of the workbench center;
3) Measuring and determining the geometric center of four upright posts on a working table of the press, and marking as a point B of the center of the four upright posts;
4) Taking the center C point of the two points of A, B as a base point on the working table surface of the press, and testing under working pressure;
a. manufacturing two high-precision pressing plates and a plurality of identical pressing blocks;
b. establishing a rectangular coordinate system on a pressing plate plane, respectively placing a pressing block in four quadrants of the pressing plate, wherein the pressing blocks in the four quadrants are uniformly distributed along a concentric circle;
c. placing another pressing plate on the four pressing blocks to form a combined pressing plate, and then placing the combined pressing plate on a working table of a press, wherein the center O of the combined pressing plate coincides with the base point C;
d. pressing according to preset working pressure, and measuring the thickness of the four pressing blocks;
e. judging the direction of the pressure center according to the thickness and the positions of the four pressing blocks:
if the thickness difference of the four pressing blocks does not reach the preset value of the working pressure test of the press, slightly moving the pressing plate to the pressing block position with smaller thickness, repeating the steps b-e again, and performing the next round of test until the thickness difference of the four pressing blocks is not larger than the preset value;
when the thickness difference is not larger than a preset value, the center O position of the combined pressing plate is the pressure center of the press, and is marked;
f. and (5) finishing the work of searching the pressure center of the press.
2. A press centering test method as claimed in claim 1, wherein: the diameter of the pressing plate is consistent with the diameter of a die for a product to be produced, the flatness and parallelism of the pressing plate are less than or equal to 0.002mm, and the hardness HRC is more than or equal to 50.
3. A press centering test method as claimed in claim 1, wherein: the pressing blocks are arranged corresponding to the pressing machine in direction, and the concentric circles of the pressing blocks are directly consistent with the measured diameter of the product to be produced.
4. A press centering test method as claimed in any one of claims 1 to 3, wherein: the materials and the sizes of the pressing blocks are the same.
5. The press centering test method as claimed in claim 4, wherein: the thickness difference of the preset value of the working pressure test of the press is 0-10 mu m.
6. The press centering test method as claimed in claim 5, wherein: the thickness difference of the preset value of the working pressure test of the press is 5 mu m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210364748.4A CN114689001B (en) | 2022-04-08 | 2022-04-08 | Press centering test method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210364748.4A CN114689001B (en) | 2022-04-08 | 2022-04-08 | Press centering test method |
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| Publication Number | Publication Date |
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| CN114689001A CN114689001A (en) | 2022-07-01 |
| CN114689001B true CN114689001B (en) | 2023-11-24 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202210364748.4A Active CN114689001B (en) | 2022-04-08 | 2022-04-08 | Press centering test method |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102672027A (en) * | 2012-04-12 | 2012-09-19 | 山东大学 | Large board blanking system for hydraulic press |
| CN107627658A (en) * | 2016-07-19 | 2018-01-26 | 新昌县镜岭镇康柳电子元件厂 | The fixed supplementary module of four-column hydraulic press mold center positioning |
| CN113418451A (en) * | 2021-08-09 | 2021-09-21 | 郑州磨料磨具磨削研究所有限公司 | Four-axis laser centering measuring device and method |
| WO2022067996A1 (en) * | 2020-09-30 | 2022-04-07 | 苏州富强科技有限公司 | Self-weight pressure maintaining mechanism |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009041373A1 (en) * | 2007-09-28 | 2009-04-02 | Toray Industries, Inc. | Method and device for manufacturing sheet having fine shape transferred thereon |
-
2022
- 2022-04-08 CN CN202210364748.4A patent/CN114689001B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102672027A (en) * | 2012-04-12 | 2012-09-19 | 山东大学 | Large board blanking system for hydraulic press |
| CN107627658A (en) * | 2016-07-19 | 2018-01-26 | 新昌县镜岭镇康柳电子元件厂 | The fixed supplementary module of four-column hydraulic press mold center positioning |
| WO2022067996A1 (en) * | 2020-09-30 | 2022-04-07 | 苏州富强科技有限公司 | Self-weight pressure maintaining mechanism |
| CN113418451A (en) * | 2021-08-09 | 2021-09-21 | 郑州磨料磨具磨削研究所有限公司 | Four-axis laser centering measuring device and method |
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| CN114689001A (en) | 2022-07-01 |
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Inventor after: Du Xiaoxu Inventor after: Feng Keming Inventor after: Wang Qingwei Inventor before: Feng Keming Inventor before: Wang Qingwei Inventor before: Du Xiaoxu |
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Effective date of registration: 20240918 Address after: 450001 121 Wutong street, Zhengzhou new and high tech Zone, Henan Patentee after: ZHENGZHOU RESEARCH INSTITUTE FOR ABRASIVES & GRINDING Co.,Ltd. Country or region after: China Patentee after: ZHENGZHOU SANMO SUPERHARD MATERIAL Co.,Ltd. Address before: 450001 121 Wutong street, Zhengzhou new and high tech Zone, Henan Patentee before: ZHENGZHOU RESEARCH INSTITUTE FOR ABRASIVES & GRINDING Co.,Ltd. Country or region before: China |