阅读说明：本技术 用于全焊接球阀阀座密封槽的压制工艺参数确定方法及半成品阀座 (Pressing process parameter determination method for all-welded ball valve seat sealing groove and semi-finished valve seat ) 是由 许世法 丁骐 古邦宇 曾品其 曾和友 胥丹红 于 2020-10-29 设计创作，主要内容包括：本发明的实施例公开一种用于全焊接球阀阀座密封槽的压制工艺参数确定方法及半成品阀座,涉及阀门技术领域,对系列化产品的继承性较强,有利于降低设计成本。所述方法,包括：建立初始的瞬态分析压制模型；设置边界条件；基于设置的所述边界条件,进行压制过程瞬态分析,获得瞬态分析结果；基于所述瞬态分析结果,修正边界条件；基于修正的边界条件,继续进行瞬态分析,获得精确的瞬态分析模型；拟定压制工艺设计变量、约束条件和目标函数；基于拟定的压制工艺设计变量、约束条件和目标函数,利用所述精确的瞬态分析模型进行优化分析,确定出目标压制工艺参数。本发明适用于全焊接球阀阀座密封槽的设计及加工。(The embodiment of the invention discloses a pressing process parameter determination method for an all-welded ball valve seat sealing groove and a semi-finished valve seat, relates to the technical field of valves, has strong inheritance to serialized products, and is beneficial to reducing the design cost. The method comprises the following steps: establishing an initial transient analysis compression model; setting a boundary condition; performing transient analysis in the pressing process based on the set boundary condition to obtain a transient analysis result; correcting a boundary condition based on the transient analysis result; based on the corrected boundary conditions, continuing transient analysis to obtain an accurate transient analysis model; drawing up design variables, constraint conditions and objective functions of the pressing process; and performing optimization analysis by using the accurate transient analysis model based on the drawn design variables, constraint conditions and objective function of the pressing process to determine target pressing process parameters. The invention is suitable for the design and processing of the sealing groove of the valve seat of the all-welded ball valve.)

1. A pressing process parameter determining method for an all-welded ball valve seat sealing groove is characterized by comprising the following steps:

establishing an initial transient analysis compression model; the model comprises a pressing die and a semi-finished valve seat;

setting a boundary condition;

performing transient analysis in the pressing process based on the set boundary condition to obtain a transient analysis result; the transient analysis result comprises stress, strain, deformation of a pressing die and deformation of a semi-finished valve seat;

correcting a boundary condition based on the transient analysis result;

based on the corrected boundary conditions, continuing transient analysis to obtain an accurate transient analysis model;

drawing up design variables, constraint conditions and objective functions of the pressing process;

and performing optimization analysis by using the accurate transient analysis model based on the drawn design variables, constraint conditions and objective function of the pressing process to determine target pressing process parameters.

2. The method of claim 1, wherein setting the boundary condition comprises: setting the mesh size, mesh type, friction coefficient and load step length.

3. The method of claim 1, wherein the formulating press process design variables comprises:

selecting an initial design variable of a pressing process;

drawing up an initial constraint condition and an objective function;

based on the initial design variables, the initial constraint conditions and the objective function of the pressing process, performing parameter sensitivity analysis by using the accurate transient analysis model, and selecting high-sensitivity parameters;

and drawing up design variables of the pressing process according to the high-sensitivity parameters.

4. The method of claim 3, wherein selecting the initial design variables for the pressing process comprises selecting a bevel distance and a bevel angle for a pressing die, selecting a cross-sectional radius for a sealing groove in the semi-finished valve seat, and selecting a chamfer angle and a free edge thickness angle for a free edge of the semi-finished valve seat.

5. The method of claim 3, wherein the target pressing process parameters include pressing die shape, pressing process parameters, and semi-finished valve seat size parameters.

6. A semi-finished valve seat for an all-welded ball valve, comprising: the valve seat comprises a valve seat body, a valve seat body and a valve body, wherein a through hole is formed along the central axis of the valve seat body, and one end of the through hole is opened on the end surface of the first end of the valve seat body;

an annular sealing groove is formed in the end face of the first end of the valve seat body around the opening of the through hole in the end face of the first end of the valve seat body; the section of the annular sealing groove is V-shaped;

an annular free edge is formed on the end face of the first end of the valve seat body in an extending mode at the outer side edge of the opening of the annular sealing groove; the shape of the free edge is in a cone cylinder shape, and the inner diameter of the free edge, close to the end face of the first end of the valve seat body, is larger than that of the free edge at the free end;

the inner side wall of the free edge corresponds to the first inner wall of the annular sealing groove, and the first inner wall of the annular sealing groove is the inner side wall of the annular sealing groove close to the central axis of the valve seat body.

7. The semi-finished valve seat according to claim 6, wherein the distance between the inner edge at the opening of the annular seal groove and the inner wall of the free edge is greater than or equal to 3mm and less than or equal to 4.5 mm;

the inner radius of the annular sealing groove is larger than or equal to 1.8mm and smaller than or equal to 2.2 mm.

8. The blank valve seat according to claim 6, wherein a distance between an inner edge at the opening of the annular seal groove and an inner wall of the free edge is less than a distance between a first inner wall inside the annular seal groove and the inner wall of the free edge.

9. The semi-finished valve seat according to claim 6, wherein an annular sealing ring with a circular cross section is arranged in the annular sealing groove, the annular sealing ring is respectively contacted with the first inner wall, the second inner wall and the inner wall of the free edge of the annular sealing groove, and a reserved space is formed between the bottom of the annular sealing ring and the bottom of the annular sealing groove.

10. A processing equipment that is used for semi-manufactured goods disk seat of all welded ball valve, its characterized in that includes: the semi-finished valve seat is fixed on the workbench, a pressing die is arranged on the stamping head, and the pressing die corresponds to the semi-finished valve seat up and down; wherein the semi-finished valve seat is as claimed in any one of the preceding claims 6 to 9.

Technical Field

The invention relates to the technical field of valves, in particular to a pressing process parameter determination method for an all-welded ball valve seat sealing groove and a semi-finished valve seat.

Background

The transportation of resources such as petroleum and natural gas by long-distance pipelines has become a major means for energy transportation in the world today. The all-welded ball valve in the long-distance conveying pipeline has the function of lifting the feet; it controls the flow direction, flow rate and pressure of the medium in the pipeline and protects the pipeline and equipment. The comprehensive technical performance of the all-welded ball valve is superior to that of other types of valve bodies with the same application, and the all-welded ball valve is a preferred valve for long-distance pipelines.

For the sealing groove of the all-welded ball valve, a drilling, milling and turning method is adopted in the prior art. The sealing groove processed in this way cannot completely fix the sealing ring, and the sealing ring can be blown out of the sealing groove when the sealing groove is opened and closed under the condition of large pressure difference, so that elements such as a pressure plate are needed to further fix the sealing ring, the volume of the valve seat is increased, and the reliability is reduced.

A plurality of anti-loosening structures are adopted in the existing sealing groove, and a sealing groove structure disclosed by patent publication No. CN201246490Y is common, and the sealing groove of the structure tightly buckles the sealing ring in the groove to prevent the sealing ring from being separated. Patent publication No. CN103480758A discloses a processing method for such a sealing structure, in which one edge of the sealing groove of the semi-finished valve seat is used as a free edge, and the sealing ring is freely placed in the sealing groove. And then gradually bending the free edge by using a rolling head to enable the free edge to buckle the sealing ring and allow part of the sealing ring to protrude out of the annular sealing groove.

The mechanical nonlinearity degree of rolling processing is high, and the existing method needs a large amount of experimental foundations; the processing method has weak inheritance to serialized products.

Disclosure of Invention

In view of this, the embodiment of the invention provides a method for determining pressing process parameters of a seal groove of an all-welded ball valve seat and a semi-finished valve seat, which have strong inheritance to serialized products and are beneficial to reducing design cost.

In a first aspect, an embodiment of the present invention provides a method for determining pressing process parameters of a seal groove of a valve seat of an all-welded ball valve, including: establishing an initial transient analysis compression model; the model comprises a pressing die and a semi-finished valve seat; setting a boundary condition; performing transient analysis in the pressing process based on the set boundary condition to obtain a transient analysis result; the transient analysis result comprises stress, strain, deformation of a pressing die and deformation of a semi-finished valve seat; correcting a boundary condition based on the transient analysis result; based on the corrected boundary conditions, continuing transient analysis to obtain an accurate transient analysis model; drawing up design variables, constraint conditions and objective functions of the pressing process; and performing optimization analysis by using the accurate transient analysis model based on the drawn design variables, constraint conditions and objective function of the pressing process to determine target pressing process parameters.

Optionally, the method includes: the setting of the boundary conditions comprises: setting the mesh size, mesh type, friction coefficient and load step length.

Optionally, the drawn press process design variables include: selecting an initial design variable of a pressing process; drawing up an initial constraint condition and an objective function; based on the initial design variables, the initial constraint conditions and the objective function of the pressing process, performing parameter sensitivity analysis by using the accurate transient analysis model, and selecting high-sensitivity parameters; and drawing up design variables of the pressing process according to the high-sensitivity parameters.

Optionally, the selecting of the initial design variables of the pressing process includes selecting an inclined plane distance and an inclined plane included angle of a pressing die, selecting a section radius of a sealing groove on the semi-finished valve seat, and selecting a chamfer angle and a free edge included angle of a free edge of the semi-finished valve seat.

Optionally, the target pressing process parameters include pressing die shape, pressing process parameters, and semi-finished valve seat size parameters.

In a second aspect, an embodiment of the present invention provides a semi-finished valve seat for an all-welded ball valve, including: the valve seat comprises a valve seat body, a valve seat body and a valve body, wherein a through hole is formed along the central axis of the valve seat body, and one end of the through hole is opened on the end surface of the first end of the valve seat body; an annular sealing groove is formed in the end face of the first end of the valve seat body around the opening of the through hole in the end face of the first end of the valve seat body; the section of the annular sealing groove is V-shaped; an annular free edge is formed on the end face of the first end of the valve seat body in an extending mode at the outer side edge of the opening of the annular sealing groove; the shape of the free edge is in a cone cylinder shape, and the inner diameter of the free edge, close to the end face of the first end of the valve seat body, is larger than that of the free edge at the free end; the inner side wall of the free edge corresponds to the first inner wall of the annular sealing groove, and the first inner wall of the annular sealing groove is the inner side wall of the annular sealing groove close to the central axis of the valve seat body.

Optionally, a distance between an inner side edge at the opening of the annular seal groove and an inner wall of the free edge is greater than or equal to 3mm and less than or equal to 4.5 mm;

the inner radius of the annular sealing groove is larger than or equal to 1.8mm and smaller than or equal to 2.2 mm.

Optionally, a distance between an inner side edge of the opening of the annular sealing groove and the inner wall of the free edge is smaller than a distance between the first inner wall inside the annular sealing groove and the inner wall of the free edge.

Optionally, be equipped with the cross-section in the ring seal groove and be circular shape ring seal, ring seal respectively with the first inner wall of ring seal groove, second inner wall and the inner wall on free limit contacts ring seal's bottom with the headspace has between ring seal groove's the bottom.

In a third aspect, an embodiment of the present invention provides a processing apparatus for a semi-finished valve seat of an all-welded ball valve, including: the semi-finished valve seat is fixed on the workbench, a pressing die is arranged on the stamping head, and the pressing die corresponds to the semi-finished valve seat up and down; wherein the semi-finished valve seat is the semi-finished valve seat of any of the previous embodiments.

According to the pressing process parameter determining method for the sealing groove of the all-welded ball valve seat, the semi-finished valve seat and the processing equipment, an initial transient analysis pressing model is established in a one-time direct pressing processing mode, after experimental verification, an accurate transient analysis model can be obtained, based on a planned pressing process design variable, constraint conditions and a target function, optimization analysis is carried out by using the accurate transient analysis model, a target pressing process parameter can be determined, the process design of the pressing mold 1 and the semi-finished valve seat 2 can be completed according to the obtained parameter, so that when similar products are designed, repeated experiments are not needed, the inheritance of the serialized products is strong, the design cost is reduced, and the working efficiency is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic flow chart of a method for determining pressing process parameters of a seal groove of a valve seat of an all-welded ball valve according to an embodiment of the invention;

FIG. 2 is a schematic structural view of a pressing die and a semi-finished valve seat before pressing in an embodiment of the invention;

fig. 3 is a schematic structural diagram of a pressing die and a semi-finished valve seat after pressing in the embodiment of the invention.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the described embodiments are only some embodiments of the invention, and 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.

Referring to fig. 1, an embodiment of the present invention provides a method for determining pressing process parameters of a seal groove of a valve seat of an all-welded ball valve, including the steps of:

and S100, establishing an initial transient analysis compression model.

The method for determining the pressing technological parameters aims at a one-time direct pressing processing mode. First, according to the mode of pressing, an initial transient analysis pressing model is established in finite element analysis software. The mould comprises a pressing mould 1 and a semi-finished valve seat 2.

Referring to fig. 2 and 3, the pressing mold 1 (also referred to as a pressing tool) is in a shape of a disc, a through hole 11 is formed in the center of the pressing mold 1, a groove 12 is formed in the pressing surface of the pressing mold 1, and a side wall 121 of the groove 12 is an inclined surface to press a free edge 24 of the semi-finished valve seat 2. The pressing die 1 and the semi-finished valve seat 2 are coaxially arranged.

The semi-finished valve seat 2 comprises a valve seat body 21, wherein a through hole 22 is formed along the central axis of the valve seat body 21, and one end of the through hole 22 is opened on the end face of the first end of the valve seat body 21; an annular seal groove 23 is formed in the end face of the first end of the valve seat body 21 around the opening of the through hole in the end face of the first end of the valve seat body 21; the section of the annular sealing groove 23 is V-shaped; an annular free edge 24 is formed on the end face of the first end of the valve seat body 21 in an extending manner at the outer side edge of the opening of the annular sealing groove 23; the free edge 24 is in a conical cylinder shape, and the inner diameter of the free edge 24 close to the end face of the first end of the valve seat body 21 is larger than that of the free edge 24 at the free end; the inner sidewall 241 of the free edge 24 corresponds to the first inner wall 231 of the annular seal groove 23, and the first inner wall 231 of the annular seal groove 23 is the inner sidewall of the annular seal groove 23 close to the central axis of the valve seat body 21.

S102, setting boundary conditions.

The boundary conditions may include: mesh size, mesh type, friction coefficient, and load step size.

And S104, performing transient analysis in the pressing process based on the set boundary conditions to obtain a transient analysis result.

The transient analysis result includes stress, strain, deformation of the pressing die 1 and the semi-finished valve seat 2, and specifically, the transient analysis result includes change of the stress, strain, deformation of the pressing die 1 and the semi-finished valve seat 2 with pressing time.

And S106, correcting the boundary condition based on the transient analysis result.

In order to obtain an accurate transient analysis model, in this step, the mesh size, mesh type, friction coefficient and load step length are corrected based on the transient analysis result, so as to perform a transient analysis experiment. In one embodiment, the modified boundary conditions include: the friction coefficient is 0.2-0.4; the unit grid sizes of the pressing die 1 and the semi-finished valve seat 2 are 0.1 in minimum and 0.5 in maximum; the load step of the pressing die 1.

And S108, based on the corrected boundary conditions, continuing transient analysis to obtain an accurate transient analysis model.

In this step, transient analysis is continued based on the corrected boundary conditions, and experimental verification is performed to obtain an accurate transient analysis model. Steps S106 to S108 may be executed repeatedly until an accurate transient analysis model is obtained. The accurate transient analysis model refers to a transient analysis model in which the analysis result can satisfy an expected value. According to the accurate transient analysis model, the pressing process can be accurately simulated.

And S110, drawing up design variables of the pressing process.

And S112, drawing up a constraint condition and an objective function.

And S114, performing optimization analysis by using an accurate transient analysis model based on the drawn design variables, constraint conditions and objective functions of the pressing process to determine target pressing process parameters.

The target pressing technological parameters comprise the shape of the pressing die 1, the size of the pressing die 1, pressing technological parameters and size parameters of the semi-finished valve seat 2.

In the embodiment, an initial transient analysis pressing model is established through a one-time direct pressing processing mode, after experimental verification, an accurate transient analysis model can be obtained, based on a proposed pressing process design variable, constraint conditions and a target function, optimization analysis is performed by using the accurate transient analysis model, target pressing process parameters can be determined, and process design of the pressing die 1 and the semi-finished valve seat 2 can be completed according to the obtained parameters.

In an embodiment, the press process design variables may be determined by a sensitivity analysis of the initial design variables, and in particular, the proposed press process design variables (step S110) may include:

s1100, selecting an initial design variable of a pressing process;

selecting the initial design variables for the pressing process may include: the inclined plane distance D1 and the inclined plane included angle D2 of the pressing die 1; the section radius D3 (also called as the inner radius of the sealing groove), the free edge meat thickness included angle D4 and the free edge chamfer radius D6 of the semi-finished valve seat 2; the pressing distance D8 between the pressing die 1 and the semi-finished valve seat 2.

And S1102, drawing up an initial constraint condition and an objective function.

In this embodiment, the initial constraint conditions are as follows:

bevel distance D1 of pressing die 1: the initial size is 9, the range is set to be 8.5-9.5D 1, the unit is: mm;

inclined plane included angle D2 of pressing die 1: the initial size is 210 degrees, and the range is set to be more than or equal to 205 degrees and less than or equal to 215 degrees D2;

sealing groove inner radius D3 of semi-finished valve seat 2: initial size 2, range setting 1.8 ≤ D3 ≤ 2.2, unit: mm;

free edge included angle D4 of semi-finished valve seat 2: the initial size is 4 degrees, and the range is set to be more than or equal to 3 degrees and less than or equal to 5 degrees by D4;

free edge chamfer radius D6 of semi-finished valve seat 2: initial size 0.5, range setting 0.3 ≤ D6 ≤ 0.7, unit: mm;

pressing distance D8 between pressing die 1 and semi-finished valve seat 2: initial size 100, range 80 ≦ D8 ≦ 120, unit: mm.

The proposed objective function is the size of the opening of the cross section of the sealing groove after pressing is finished.

Specifically, the objective function is formulated as:

wherein: d5 is the opening size of the cross section of the sealing groove after pressing is finished, and the value is(x1, y1) and (x0, y0) are the plane coordinates of the two vertices of the opening, respectively.

The constraints on the opening size D5 are: d5 is not more than 4.5 mm.

And S1104, performing parameter sensitivity analysis by using an accurate transient analysis model based on the initial design variables, the initial constraint conditions and the objective function of the pressing process, and selecting high-sensitivity parameters.

In this step, parameter sensitivity analysis is performed to select high sensitivity parameters.

And S1106, drawing up design variables of the pressing process according to the high-sensitivity parameters.

In this step, the design variables are reset according to the high sensitivity parameters. And the value range of the 3 parameters with the maximum sensitivity is expanded. The remaining design parameters are given by the process designer within the value range.

The constraint of setting the objective function opening distance D5 is: d5 is not more than 4 mm.

In the embodiment, an initial transient analysis pressing model is established in a one-time direct pressing mode, an accurate transient analysis model can be obtained after experimental verification, target pressing process parameters can be determined by performing optimization analysis on the accurate transient analysis model based on a proposed pressing process design variable, constraint conditions and a target function, and process design of the pressing die 1 and the semi-finished valve seat 2 can be completed according to the obtained parameters.

The influence of each design parameter can be determined through parameter sensitivity analysis, so that the design variable with the largest influence on the target function can be known through parameter sensitivity analysis in the design process, the difficulty in selecting process parameters, structural parameters and the like is reduced, and the efficiency of design results is improved.

The method of the embodiment can be suitable for the production of series products. The repeated structural design, process design, experiment times and the like of similar products are reduced. The design cost is reduced, and the working efficiency is improved.

Referring to fig. 2 and 3, an embodiment of the present invention further provides a semi-finished valve seat 2 for an all-welded ball valve, including: the valve seat comprises a valve seat body 21, a through hole 22 is formed along the central axis of the valve seat body 21, and one end of the through hole 22 is opened on the end face of the first end of the valve seat body 21; an annular seal groove 23 is formed in the end face of the first end of the valve seat body 21 around the opening of the through hole 22 in the end face of the first end of the valve seat body 21; the section of the annular sealing groove 23 is V-shaped; an annular free edge 24 is formed on the end face of the first end of the valve seat body 21 in an extending manner at the outer side edge of the opening of the annular sealing groove 23; the free edge 24 is in a conical cylinder shape, and the inner diameter of the free edge 24 close to the end face of the first end of the valve seat body 21 is larger than that of the free edge 24 at the free end;

the inner sidewall 241 of the free edge 24 corresponds to the first inner wall 231 of the annular seal groove 23, and the first inner wall 231 of the annular seal groove 23 is the inner sidewall of the annular seal groove 23 close to the central axis of the valve seat body 21.

In this embodiment, the cross-sectional shape of the annular seal groove 23 is V-shaped, and the inner sidewall 241 of the free edge 24 corresponds to the first inner wall 231 of the annular seal groove 23, so that when the free edge 24 is pressed from the outer side surface of the free edge 24, the seal ring is pressed in the V-shaped annular seal groove 23 by the inner sidewall of the free edge 24.

The semi-finished valve seat 2 of the embodiment can be designed and processed according to the target pressing process parameters determined by the method embodiment, repeated experiments are not needed when similar products are designed, the succession of the series products is strong, the design cost is reduced, and the working efficiency is improved.

In one embodiment, the distance D05 between the inner edge of the opening of the annular sealing groove 23 and the inner wall of the free edge 24 is greater than or equal to 3mm and less than or equal to 4.5 mm; the inner radius of the annular sealing groove 23 is more than or equal to 1.8mm and less than or equal to 2.2 mm. In one example, the distance between the inner edge of the opening of the annular sealing groove 23 and the inner wall of the free edge 24 is 4mm, and the inner radius of the annular sealing groove 23 is 2mm, so that after the free edge 24 is pressed, a part of the sealing ring leaks out of the opening of the annular sealing groove 23, and the majority of the sealing ring is pressed in the annular sealing groove 23, so that the sealing ring can be prevented from being accidentally removed from the annular sealing groove 23.

In an embodiment, the distance between the inner edge of the opening of the ring-shaped sealing groove 23 and the inner wall of the free edge 24 is smaller than the distance between the first inner wall of the ring-shaped sealing groove 23 and the inner wall of the free edge 24, so that the sealing ring can be pressed towards the bottom of the V-shaped ring-shaped sealing groove 23 when the free edge 24 is pressed.

In an embodiment, the annular sealing ring 3 with a circular cross section is arranged in the annular sealing groove 23, the annular sealing ring 3 is respectively contacted with the first inner wall 231, the second inner wall 232 and the inner wall 241 of the free edge 24 of the annular sealing groove 23, a reserved space is arranged between the bottom of the annular sealing ring 3 and the bottom of the annular sealing groove 23, so that when the free edge 24 is pressed, the sealing ring can be extruded towards the bottom of the V-shaped annular sealing groove 23, after the pressing is completed, the annular sealing groove 23 is trapezoidal, that is, the sealing ring pressed in the annular sealing groove 23 is deformed, the cross section of the sealing ring is trapezoidal, the deformed sealing ring can be firmly embedded in the sealing groove, accidental disengagement is prevented, and the sealing reliability is increased.

The semifinished valve seats 2 of the above-described embodiments can be applied to the above-described method embodiments.

Referring to fig. 2 and 3, an embodiment of the present invention further provides a processing apparatus for a semi-finished valve seat of an all-welded ball valve, including: the semi-finished valve seat punching device comprises a workbench and a punching head, wherein a semi-finished valve seat 2 is fixed on the workbench, a pressing die 1 is arranged on the punching head, and the pressing die 1 corresponds to the semi-finished valve seat 2 up and down; wherein the semi-finished valve seat 2 is the semi-finished valve seat 2 of any one of the previous embodiments.

The pressing die 1 and the semi-finished valve seat 2 of the embodiment can be designed and processed according to the target pressing process parameters determined by the method embodiment, repeated experiments are not needed when similar products are designed, the inheritance of serialized products is strong, the design cost is reduced, and the working efficiency is improved.

The pressing die 1 is disc-shaped, the pressing die 1 and the semi-finished valve seat 2 are coaxially arranged, a through hole 11 is formed in the center of the pressing die 1, a groove 12 is formed in the pressing surface of the pressing die 1, and the side wall 121 of the groove 12 is an inclined plane.

In one example, the included angle D2 between the slope 121 and the plane of the groove bottom (also referred to as the slope included angle) is greater than: 205 DEG-D2-215 DEG, and the distance D1 from the edge of the through hole 11 in the center of the pressing die 1 to the intersection of the inclined surface 121 and the groove bottom (also referred to as inclined surface distance) is in the range of: d1 is more than or equal to 8.5mm and less than or equal to 9.5 mm.

The pressing distance between the pressing die 1 and the semi-finished valve seat 2 is within the range of D8: d8 is more than or equal to 80mm and less than or equal to 120 mm.

The embodiment of the invention firstly establishes a finite element transient analysis model aiming at the pressing process, and obtains an accurate transient analysis model through correcting boundary conditions through proper experiments; based on an accurate transient analysis model, parameter sensitivity analysis is carried out on design variables, technological parameters with the highest sensitivity (namely the design variables with the largest influence on the target function) are found out, and the technological parameters of the valve seat and the pressing die 1 can be obtained after the technological parameters to be optimized are optimized and analyzed by using the accurate transient analysis model, so that the problems that the design of the existing pressing process is difficult and the experiment is excessively depended on are solved. The process design method of the embodiment of the invention applies the parameter optimization analysis of the finite element technology to the process design, and is a reverse design.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments.

In particular, as for the apparatus embodiment, since it is substantially similar to the method embodiment, the description is relatively simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

For convenience of description, the above devices are described separately in terms of functional division into various units/modules. Of course, the functionality of the units/modules may be implemented in one or more software and/or hardware implementations of the invention.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.