CN111842741A - Internal contact type spin rolling method for tubular workpiece - Google Patents

Internal contact type spin rolling method for tubular workpiece Download PDF

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CN111842741A
CN111842741A CN202010867683.6A CN202010867683A CN111842741A CN 111842741 A CN111842741 A CN 111842741A CN 202010867683 A CN202010867683 A CN 202010867683A CN 111842741 A CN111842741 A CN 111842741A
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tubular
blank
angle
tubular blank
annular
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CN111842741B (en
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赵春江
许镱巍
李天宝
李华英
仇云龙
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Taiyuan University of Science and Technology
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21HMAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
    • B21H1/00Making articles shaped as bodies of revolution
    • B21H1/18Making articles shaped as bodies of revolution cylinders, e.g. rolled transversely cross-rolling

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Abstract

The invention discloses an internal contact type spin rolling method for a tubular workpiece, which comprises the following steps of sleeving a tubular blank to be processed on a core mold, and enabling the central axes of the core mold and the tubular blank to coincide; starting to rotate the annular cylindrical mold in the same direction, and feeding the core mold along the direction of the central axis; and (3) putting the tubular blank into an annular cylindrical die, carrying out rotary rolling on the tubular blank, and processing the unprocessed end into a finished product. The ring-shaped die rotary rolling method adopts the inner surface of the die and the outer surface of the pipe-shaped workpiece to carry out rotary rolling processing, the working surface is the inner arc ring surface of the ring-shaped die, a larger wrap angle is formed in a contact deformation area with a pipe-shaped blank, the material has smaller circumferential deformation and radial deformation rate, and simultaneously has larger metal axial elongation, thereby being a technology for economically and rapidly forming a thin-wall revolving body part.

Description

Internal contact type spin rolling method for tubular workpiece
Technical Field
The invention relates to the technical field of spinning and roll forming, in particular to an internal contact type spin rolling method for a tubular workpiece.
Technical Field
The technique of spinning or rolling a tubular workpiece is generally to rotate a die to force the metal from a point to a line and from a line to a surface while imparting a certain pressure in a certain direction to deform and flow the metal material in this direction to form a set shape. Most of the existing spinning machines and rolling mills are in contact with the outer surface of a deformation die and the outer surface of a workpiece, and the contact wrap angle of a spinning wheel or a roller of the existing spinning machines or rolling mills and a blank contact deformation area of a tubular workpiece is small, so that the defects of longitudinal cracks, obvious ripples on the surface and the like are easily generated.
Disclosure of Invention
The invention aims to provide an internal contact type spin rolling method for a tubular workpiece, which aims to solve the problems in the prior art, can realize higher metal axial elongation and is a technology for economically and quickly forming a thin-wall revolving body part.
In order to achieve the purpose, the invention provides the following scheme: the invention provides an internal contact type spin rolling method for a tubular workpiece, which specifically comprises the following steps:
step 1, sleeving a pipe barrel-shaped blank to be processed on a core mold, and enabling central axes of the core mold and the pipe barrel-shaped blank to coincide;
step 2, starting to rotate the annular die, and feeding the core die along the direction of the central axis; the tubular blank enters an annular cylindrical die; the annular curved surface of the annular cylindrical mold is in contact with the outer surface of the tubular blank and is pressed in along the radial direction of the tubular blank, and the pressing depth forms a thinning amount delta t; the tube-shaped blank is subjected to spin rolling, and the unprocessed end is processed into a finished end;
and 3, finishing the spin rolling of the tubular blank by the annular cylindrical die.
Preferably, a common central axis of the tubular blank and the core mold is X1, and an axis of the annular mold is X2.
Preferably, the annular cylinder-shaped die is an annular rotary wheel.
The spin rolling in the step 2 specifically comprises the following steps: the annular curved surface and the contact surface of the tubular blank form a lowest contact point and a highest contact point, the lowest contact point makes a perpendicular line towards the central axis of the tubular blank, the perpendicular foot O is taken as an origin, and the central axis of the tubular blank is taken as an x axis to establish a three-dimensional spin-rolling coordinate system; the z-axis forms a machining angle alpha with the highest contact point;
and (3) spatially rotating the annular cylindrical mold, wherein a projection included angle of the central axis of the annular cylindrical mold on an x axis of a three-dimensional spin-rolling coordinate system forms an adjusting angle beta, and a projection included angle on a z axis forms a feeding angle gamma.
Preferably, step 2 can be performed simultaneously after the thinning amount Δ t is formed in step 1, and there is no precedence order.
The minimum inner diameter d of the annular curved surface needs to satisfy the following conditions: the smaller of d cos beta and d cos gamma is larger than the outer diameter of the unprocessed end of the tubular blank.
The feeding angle gamma is related to the rotating speed n of the annular cylindrical die and the relative feeding linear speed v of the annular cylindrical die and the tubular blank, and is represented as follows:
Figure BDA0002650207530000021
the tubular blank and the annular cylindrical die rotate along the central axial directions of the tubular blank and the annular cylindrical die in the same direction.
The angle of the processing angle alpha is 10-40 degrees; adjusting the angle of the angle beta to be +/-20 degrees; the angle of the feed angle gamma is + -5 deg..
The invention discloses the following technical effects: 1. the invention realizes the spin-rolling process by simultaneously or independently changing the thinning amount delta t, the adjusting angle beta and the feed angle gamma, and changes the processing angle.
2. The annular cylinder-shaped die can be in an inclined state relative to the tubular blank by changing the adjusting angle beta and the feeding angle gamma, the wrap angle range of the annular cylinder-shaped die and the tubular blank rotary rolling deformation area can be adjusted, and axial component velocity and thrust which are beneficial to the flowing of metal materials are generated, so that the metal flowing capacity is improved, and the deformation resistance and the stress on dangerous sections are reduced; the defects of metal accumulation, diameter expansion, pipe bending, longitudinal cracks, obvious ripples on the surface and the like which are easily caused by a general external spinning wheel spinning method can be avoided.
3. In the working state, the tubular blank and the core mold are axially fed relative to the annular die along the central line direction of the tubular blank, and the deformation area of the annular blank is the inner containing surface of the annular rotating wheel, so that the material is difficult to generate circumferential additional deformation; meanwhile, compared with an external contact type spin rolling mode, the contact deformation area is increased, the spin rolling force is increased, and the spin permeability is enhanced.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive labor.
FIG. 1 is a schematic diagram of the initial state structural arrangement of the present invention.
Fig. 2 is a schematic view of a machining angle α according to an embodiment of the present invention.
Fig. 3 is a schematic structural arrangement diagram of the second embodiment of the present invention.
Fig. 4 is a schematic view of the xy plane projection of the second adjustment angle β according to the embodiment of the present invention.
Fig. 5 is a schematic projection diagram of a second advancing angle γ on the yz plane according to the embodiment of the present invention.
Fig. 6 is a schematic diagram of the arrangement of three structures in the embodiment of the invention.
Wherein, 1-core mould, 2-tubular blank, 3-annular tubular mould, 31-annular curved surface, d 1-annular curved surface inner diameter, alpha-processing angle, beta-adjusting angle, gamma-feeding angle, X1-core mould and tubular blank axis and X2-first annular tubular mould axis;
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description thereof.
The invention provides an internal contact type spin rolling method for a tubular workpiece, which specifically comprises the following steps:
step 1, sleeving a pipe barrel-shaped blank 2 to be processed on a core mold 1, and enabling the central axes of the core mold 1 and the pipe barrel-shaped blank 2 to coincide;
step 2, starting to rotate the annular die 3, and feeding the core die 1 along the direction of the central axis; the tubular blank 2 enters an annular tubular die 3; the annular curved surface 31 of the annular cylindrical die 3 is contacted with the outer surface of the tubular blank 2 and is pressed in along the radial direction of the tubular blank 2, and the pressing depth forms the thinning amount delta t; the tube-shaped blank 2 is subjected to spin rolling, and the unprocessed end is processed into a finished end;
and 3, finishing the spin rolling of the tubular blank 2 through the annular cylindrical die 3.
The spin rolling in the step 2 specifically comprises the following steps: the annular curved surface 31 and the contact surface of the tubular blank 2 form a lowest contact point and a highest contact point, the lowest contact point makes a perpendicular line towards the central axis of the tubular blank 2, the perpendicular foot O is taken as an origin point, and the central axis of the tubular blank 2 is taken as an x axis to establish a three-dimensional spin-rolling coordinate system; the z-axis forms a machining angle alpha with the highest contact point;
the annular cylinder-shaped die 3 is rotated in space, the projection included angle of the central axis of the annular cylinder-shaped die 3 on the x axis of the three-dimensional rotary rolling coordinate system forms an adjusting angle beta, and the projection included angle on the z axis forms a feeding angle gamma.
The minimum inner diameter d of the annular curved surface 31 is required to satisfy: the smaller of d · cos β and d · cos γ is larger than the outer diameter of the unprocessed end of the tubular blank 2.
The feeding angle γ is related to the rotation speed n of the annular cylindrical mold 3 and the relative feeding linear speed v of the annular cylindrical mold 3 and the tubular blank 2, and is expressed as:
Figure BDA0002650207530000051
the tubular blank 2 and the annular cylindrical die 3 rotate in the same direction along the respective central axes.
The angle of the processing angle alpha is 10-40 degrees; adjusting the angle of the angle beta to be +/-20 degrees; the angle of the feed angle gamma is + -5 deg..
In the embodiment of the invention, the outer dimension of the core mould 1 is selected as the outer diameter
Figure BDA0002650207530000052
The external dimension of the tubular blank 2 is the external diameter
Figure BDA0002650207530000053
Wall thickness 3.5mm, inner diameter
Figure BDA0002650207530000054
Minimum diameter of the annular curved surface 31
Figure BDA0002650207530000055
The machining angle α is 30 °. The processing technological parameters are as follows: the feeding speed v of the tubular blank 2 is 2mm/s and the rotating speed n of the annular die 3 is 100 rpm.
In the first embodiment of the present invention, as shown in fig. 2, the initial feeding state is set as the adjustment angle β is 0, and the feeding angle γ is 0; the inner surface of the tubular blank 2 is sleeved on the outer surface of the core mould 1, and the annular curved surface 31 is covered on the outer surface of the tubular blank 2 and forms internal contact with the outer surface.
The annular curved surface 31 is pressed into the outer surface of the blank at the unprocessed end of the tubular blank 2 along the radial direction of the tubular blank 2, the pressing depth is reduced by delta t, the closest contact point of the annular curved surface 31 and the tubular blank 2 to the axis X1 is set as 21, and the farthest contact point is set as 22; taking the contact point 21 as a perpendicular line to the axis X1, taking the vertical leg as O, taking the axis X1 as an axis, establishing a three-dimensional spin-rolling coordinate system, and taking an angle formed by the points 21 and 22 by taking the point O as a vertex as a processing angle alpha;
in the working state of the rotary rolling, the following 2 relative changes are generated relative to the initial state: 1) the tubular blank 2 and the core mold 1 are stationary, and the contact point 21 moves along the straight line L together with the annular tubular mold 3 to change the thinning amount Δ t; 2) the contact points 21 and 22 are used as supporting points, the annular cylindrical die 3 rotates in space, an axis X2 of the annular cylindrical die and an X-axis projection included angle in a three-dimensional rotary rolling coordinate system form an adjusting angle beta, and a z-axis projection included angle in the three-dimensional rotary rolling coordinate system forms a feeding angle gamma. The above relative changes 1) and 2) are not in sequence.
And (3) carrying out spin rolling on the tubular blank 2 through a tubular die to form a finished product of a thinned finished end.
In the second embodiment of the invention, the annular cylindrical mold is an annular rotary wheel; as shown in fig. 4, the adjustment angle β is 10 °, and the feed angle γ is 0.5 °; wherein the adjusting angle beta and the feeding angle gamma rotate in the same direction; the annular curved surface 31 is press-fitted into the outer surface of the tubular blank 2 to an initial reduction Δ t of 1.5mm, and the both are in an inner contact state. The core mold 1 and the tube-shaped blank 2 are positively rotated about their axis X1 and are axially fed in the direction of the arrow shown in fig. 4 along X1. The tubular workpiece blank 2 contacts the inner arc surface 31 of the annular rotary wheel to drive the annular rotary wheel 3 to rotate around the axis X2.
In the third embodiment of the invention, the annular cylindrical mold is an annular rotary wheel; as shown in fig. 6; in the figure, the adjusting angle β is 10 °, the feeding angle γ 1 is 0.5 °, and γ 2 is-0.5 °; wherein the adjustment angle beta rotates opposite to the feed angle gamma; the annular curved surface 31 is press-fitted into the outer surface of the tubular blank 2 to an initial thinning amount Δ t of 1.5mm, and the both are in an inner contact state. The mandrel 1 and the tubular blank 2 are fed axially along X1, as indicated by the arrow in fig. 6, the circular spinning wheel 3 being actively rotated about its axis X2. The tube blank 2 is brought into contact with the annular ring inner arc surface 31 to rotate the tube cylindrical blank 2 and the core mold 1 about the axis X1 thereof.
The invention provides a method for rolling a cylindrical die by a rotary rolling method, which adopts the inner surface of the die and the outer surface of a cylindrical workpiece to perform rotary rolling processing, the working surface is the inner arc ring surface of the cylindrical die, a larger wrap angle is formed in a contact deformation area with a cylindrical blank, the material has smaller circumferential deformation and radial deformation speed, and simultaneously has larger metal axial elongation, thereby being a technology for economically and rapidly forming a thin-wall revolving body part.
In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, are merely for convenience of description of the present invention, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.
The above-mentioned embodiments are only for describing the preferred mode of the present invention, and do not limit the scope of the present invention, and various modifications and improvements made to the technical solution of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims (6)

1. A contact type spin rolling method in a tubular workpiece is characterized by comprising the following steps:
step 1, sleeving a pipe barrel-shaped blank (2) to be processed on a core mold (1) to enable the central axes of the core mold (1) and the pipe barrel-shaped blank (2) to coincide;
step 2, starting to rotate the annular cylindrical mold (3), and feeding the core mold (1) along the direction of the central axis; the tubular blank (2) enters an annular tubular die (3); the annular curved surface (31) of the annular cylindrical die (3) is in contact with the outer surface of the tubular blank (2), and is pressed in along the radial direction of the tubular blank (2), and the pressing depth forms a thinning amount delta t; the tube-shaped blank (2) is subjected to spin rolling, and the unprocessed end is processed into a finished end;
and 3, finishing the spin rolling of the tubular blank (2) through the annular cylindrical die (3).
2. The double-ring roller internal contact type spin-rolling method for the tubular workpiece according to claim 1, wherein the spin-rolling in the step 2 is specifically as follows: the annular curved surface (31) and the contact surface of the tubular blank (2) form a lowest contact point and a highest contact point, the lowest contact point makes a perpendicular line towards the central axis of the tubular blank (2), the vertical foot O is taken as an origin, and the central axis of the tubular blank (2) is taken as an x axis to establish a three-dimensional spin-rolling coordinate system; the z-axis forms a machining angle alpha with the highest contact point;
and (3) spatially rotating the annular cylindrical mold (3), wherein a projection included angle of the central axis of the annular cylindrical mold (3) on an x axis of a three-dimensional rotary rolling coordinate system forms an adjusting angle beta, and a projection included angle on a z axis forms a feeding angle gamma.
3. The double-ring roller internal contact type spin-rolling method of tubular workpieces according to claim 2, wherein the minimum inner diameter d of the annular curved surface (31) is required to satisfy the following requirements: the smaller of d cos beta and d cos gamma is larger than the outer diameter of the unprocessed end of the tubular blank (2).
4. The double-ring roller internal contact type rotary rolling method for tubular workpieces according to claim 2, characterized in that the feed angle γ is related to the rotation speed n of the ring-shaped die (3) and the relative feed linear speed v of the ring-shaped die (3) and the tubular blank (2) and is expressed as:
Figure FDA0002650207520000021
5. the double-ring roller internal contact type spin-rolling method of a tubular workpiece according to claim 1, characterized in that the tubular blank (2) and the annular die (3) rotate in the same direction along the respective central axes.
6. The double-ring roller internal contact type spin-rolling method of the tubular workpiece according to claim 2, wherein the machining angle α is 10 ° -40 °; adjusting the angle of the angle beta to be +/-20 degrees; the angle of the feed angle gamma is + -5 deg..
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113245428A (en) * 2021-06-21 2021-08-13 西北工业大学 Oblique rolling type spinning forming method for cylindrical part with inner ribs
CN113369307A (en) * 2021-03-15 2021-09-10 太原科技大学 Ring roller rotary rolling mill

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101433916A (en) * 2007-11-14 2009-05-20 金凯岷 Mandrel power mechanism for cold rolling machine
CN103128171A (en) * 2011-12-02 2013-06-05 沈阳黎明航空发动机(集团)有限责任公司 High temperature alloy thin-walled sleeve molding method
CN106734301A (en) * 2017-02-20 2017-05-31 中北大学 A kind of large-diameter thin-wall seamless pipe rotary extrusion forming method
CN109201832A (en) * 2017-12-13 2019-01-15 中国航空制造技术研究院 A kind of short mould rotary pressing moulding device
CN110479842A (en) * 2019-08-02 2019-11-22 武汉理工大学 Large thin-wall Y shape ring rolling-spinning combined shaping method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101433916A (en) * 2007-11-14 2009-05-20 金凯岷 Mandrel power mechanism for cold rolling machine
CN103128171A (en) * 2011-12-02 2013-06-05 沈阳黎明航空发动机(集团)有限责任公司 High temperature alloy thin-walled sleeve molding method
CN106734301A (en) * 2017-02-20 2017-05-31 中北大学 A kind of large-diameter thin-wall seamless pipe rotary extrusion forming method
CN109201832A (en) * 2017-12-13 2019-01-15 中国航空制造技术研究院 A kind of short mould rotary pressing moulding device
CN110479842A (en) * 2019-08-02 2019-11-22 武汉理工大学 Large thin-wall Y shape ring rolling-spinning combined shaping method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113369307A (en) * 2021-03-15 2021-09-10 太原科技大学 Ring roller rotary rolling mill
CN113369307B (en) * 2021-03-15 2023-09-26 太原科技大学 Ring roller rotary rolling mill
CN113245428A (en) * 2021-06-21 2021-08-13 西北工业大学 Oblique rolling type spinning forming method for cylindrical part with inner ribs

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