阅读说明：本技术 一种大尺寸近回转体发动机唇口成形方法 (Method for forming lip of large-size near-revolving-body engine ) 是由 李奎 李善良 倪兴屹 鲁帆 孟文博 于 2021-07-27 设计创作，主要内容包括：本发明公开了一种大尺寸近回转体发动机唇口成形方法,该方法使用旋压模和胀形模进行二次成形,旋压模具包括旋压胎和旋压轮,旋压胎的法兰面根据唇口零件模型可设置在不同平面,两个旋压轮分别位于环形唇口内圈和外圈,两个旋压轮可以实现协同运动,胀形模具包括凹模、压边圈、充液口、排液口、承压块,充液口设置在压料圈圆滑过渡区中间位置,排液口设置在凹模回转中心位置,承压块设置在发动机唇口零件的工序件法兰面的两侧,沿凹模回转轴线均匀分布。本发明结构简单,无复杂结构,制造成本低,周期短。回弹小,成形精度高。(The invention discloses a large-size near-revolving body engine lip forming method, which uses a spinning die and an expansion die to carry out secondary forming, wherein the spinning die comprises a spinning tire and spinning wheels, the flange surface of the spinning tire can be arranged on different planes according to a lip part model, the two spinning wheels are respectively positioned on an inner ring and an outer ring of an annular lip, the two spinning wheels can realize cooperative motion, the expansion die comprises a female die, a blank holder, a liquid charging port, a liquid discharging port and a pressure bearing block, the liquid charging port is arranged at the middle position of a smooth transition area of the blank holder, the liquid discharging port is arranged at the revolving center position of the female die, and the pressure bearing blocks are arranged at two sides of the flange surface of a process part of an engine lip part and are uniformly distributed along the revolving axis of the female die. The invention has simple structure, no complex structure, low manufacturing cost and short period. The rebound is small, and the forming precision is high.)

1. The utility model provides a big size nearly solid of revolution engine lip forming method, its characterized in that uses spinning die and bulging die to carry out the secondary forming, the spinning die includes spinning child and spinning wheel, the flange face of spinning child can set up in different planes according to lip part model, two spinning wheels are located annular lip inner circle and outer lane respectively, two spinning wheels can realize the concerted movement, the bulging die includes the die, the blank holder, fill liquid mouth, the leakage fluid dram, the bearing block, fill liquid mouth sets up in the pressure holder rounding off district intermediate position, the leakage fluid dram sets up in the die centre of gyration position, the bearing block sets up the both sides at the process spare flange face of engine lip part, along the die axis of gyration evenly distributed, the forming method includes the following step:

step 1, constructing a molded surface of a spinning die;

step 2, constructing a female die molded surface of the expansion die;

step 3, constructing a blank holder pressing surface;

step 4, manufacturing a spinning die by using the molded surface of the constructed spinning die;

step 5, manufacturing an bulging female die by using the structural bulging female die molded surface, and manufacturing a blank holder by using the structural blank holder pressing surface;

step 6, spinning and forming a standard revolving body engine lip process piece by adopting a mode of simultaneously spinning the inner side and the outer side of an annular lip according to the manufactured spinning die;

step 7, according to the manufactured bulging female die, bulging the formed rotary body engine lip process part to the required shape radian of the lip part in a liquid bulging mode;

and 8, cutting the expanded part along the contour line of the lip part to obtain the final contour of the engine lip part.

2. The method for forming a large-size near-rotary-body engine lip according to claim 1, wherein the step 1 is to construct a spinning die profile by the following specific process: the molded surface of the spinning die comprises a flange surface, a revolution surface and a transition part of the flange surface and the revolution surface, wherein the size of the normal section of the revolution surface is smaller than the minimum size of the normal section of the lip model, and the revolution central axis of the part is determined according to the projection surface of the annular lip model. The minimum width section of the lip part is measured and determined in a plane passing through the central rotation axis, the minimum width section is reduced and offset along the normal direction, the offset curve is rotated along the central rotation axis, the offset of the minimum width section is controlled to ensure that the revolution surface is enveloped in the annular lip model, the flange surface is expanded to the normal direction through the edge external extension line of the revolution surface, smooth transition is adopted between the revolution surface and the annular flange surface, and the constructed process profile is used as the spinning die profile.

3. The method for forming the lip of the large-size near-revolving body engine according to claim 1, wherein the step 2 is to construct the female die surface of the expansion die by the following specific process: the flange surface of the female die molded surface is of a plane structure, the flange surface is constructed according to the outward insertion extension line of the edge line of the lip model along the normal direction of the rotation axis, the flange surface and the flange surface are in the same plane, and the flange surface and the lip model are in smooth transition to construct the bulging female die molded surface.

4. The method for forming the lip of the large-size near-revolving body engine according to claim 1, wherein the step 3 is to construct a blank holder pressing surface, and the concrete process is as follows: the blank holder pressing surfaces are obtained by the deflection of the flange surfaces of the female die molded surfaces, and smooth transition is adopted among the blank holder pressing surfaces.

5. The method for forming the lip of the large-size near-revolving-body engine according to claim 1, wherein in the step 6, the number of the spinning rollers is 2, the spinning rollers are respectively arranged on the inner ring and the outer ring of the annular lip part, and the 2 spinning rollers can cooperatively act to spin the inner ring and the outer ring of the annular lip part at the same time.

Technical Field

The invention relates to a forming method of a large-size engine lip, in particular to an integral forming method of a lip part with an annular structure, wherein the shape of the lip part is similar to that of a revolving body.

Background

The turbofan engine has the advantages of large thrust, high propulsion efficiency, low noise, low fuel consumption rate, long airplane range and the like, and is widely applied to large and medium military and civil airliners and transport planes. In order to meet the requirement of engine light weight, engine lip parts are mostly formed by adopting 2-series aluminum alloy plates with the thickness of 1-2 mm, and patent CN 110899501A and patent CN 109692911A provide a sheet material engine lip integral forming method. Taking 1.2mm of 2A12 aluminum alloy as an example, in the material specification GJB 2053A-2015, the maximum width of a 1.2mm 2A12 aluminum alloy plate is 2000mm, so the maximum annular lip part size which can be formed by adopting the plate with the specification is not more than 1600mm, for a lip part which is larger than 1600mm, the plate integral forming process cannot be adopted due to the limitation of the material width, if a special aluminum alloy plate is specially rolled, the plate cost is sharply increased due to the processing capacity of a supplier, the mold cost and other factors, and the special plate is not cited in the material specification, so that difficulties are caused to aeronautical manufacturers in process management, factory acceptance, quality record and other aspects. Therefore, no proper process method is found when large-size and oversized annular engine lip parts are formed at present.

Aiming at the problems, a process method for integrally forming a lip of a near-revolving body engine is developed, and the restriction of the width of a plate is solved. The manufacturing problem of large-size and oversized annular lip parts is solved by a rigid-flexible combined forming mode.

Disclosure of Invention

A large-size near-revolving body engine lip forming method uses a spinning die and an expansion die to carry out secondary forming, the spinning die comprises a spinning tire and two spinning wheels, the flange surface of the spinning tire can be arranged on different planes according to a lip part model, the two spinning wheels are respectively positioned on an inner ring and an outer ring of an annular lip, the two spinning wheels can realize cooperative motion, the expansion die comprises a female die, a blank holder, a liquid filling port, a liquid discharging port and a bearing block, the liquid filling port is arranged in the middle of a smooth transition area of the blank holder, the liquid discharging port is arranged in the revolving center position of the female die, the bearing blocks are arranged on two sides of the flange surface of a process part of the engine lip part and are uniformly distributed along the revolving axis of the female die, and the forming method comprises the following steps:

1, constructing a molding surface of a spinning die: the molded surface of the spinning die comprises a flange surface, a revolution surface and a transition part of the flange surface and the revolution surface, wherein the size of the normal section of the revolution surface is smaller than the minimum size of the normal section of the lip model, and the revolution central axis of the part is determined according to the projection surface of the annular lip model. The minimum width section of the lip part is measured and determined in a plane passing through a revolution axis, the minimum width section is shifted along a normal direction, a shifted curve rotates along the revolution axis, the envelope of a revolution surface in an annular lip model is ensured by controlling the shift of the minimum width section, a flange surface is expanded to the normal direction through an edge external extension line of the revolution surface, smooth transition is adopted between the revolution surface and the annular flange surface, and the constructed process profile is used as a spinning die profile.

2, constructing a female die molded surface of the bulging die: the flange surface of the female die molded surface is of a plane structure, the flange surface is constructed according to the outward insertion extension line of the edge line of the lip model along the normal direction of the rotation axis, the flange surface and the flange surface are in the same plane, and the flange surface and the lip model are in smooth transition to construct the bulging female die molded surface.

3, constructing a blank holder pressing surface: the blank holder pressing surfaces are obtained by the deflection of the flange surfaces of the female die molded surfaces, and smooth transition is adopted among the blank holder pressing surfaces;

and 4, manufacturing the spinning die by using the molded surface of the constructed spinning die.

5, manufacturing the bulging female die by using the structural bulging female die molded surface, and manufacturing the blank holder by using the structural blank holder pressed surface.

6 according to the manufactured spinning die, a standard revolving body engine lip process part is spun and formed in a mode that the inner side and the outer side of the annular lip are spun and formed simultaneously, the number of spinning wheels during spinning and forming is 2, the spinning wheels are respectively positioned on the inner ring and the outer ring of the annular lip part, the 2 spinning wheels can act in a synergistic mode, and meanwhile, the inner ring and the outer ring of the annular lip part are spun and formed.

And 7, according to the manufactured bulging female die, bulging the formed rotary body engine lip process part to the required shape radian of the lip part in a liquid bulging mode.

And 8, cutting the expanded part along the contour line of the lip part to obtain the final contour of the engine lip part.

The invention has the beneficial effects that:

the mold has simple structure and low manufacturing cost. The die structure related to the annular lip forming method provided by the patent CN 110899501A and the patent CN 109692911A is complex, the manufacturing cost is high, and the spinning die and the bulging die in the large-size near-revolving body engine lip forming method provided by the invention are simple in structure, free of complex structures, low in manufacturing cost and short in period.

The rebound is small, and the forming precision is high. Because the lip part is similar to a revolving body structure, after the lip part is spun, the revolving body working procedure part is close to a part product, and then the sheet material is tightly attached to the molded surface of the female die through the bulging effect of the liquid medium to generate uniform plastic deformation, and the stress state is a bidirectional tensile stress state, so that the rebound phenomenon after the part is formed can be effectively reduced.

The lip part of the large-size and oversized near-revolving body engine can be formed. If a thin plate is used to form the engine lip part, the larger diameter lip requires the larger width of the sheet material. Because of the economical efficiency and the practicability, the ultra-wide plate needs to be specially made, the cost is higher, and the period is longer. The mode of spinning first and then bulging is adopted, so that the restriction on the width of a thin plate is reduced, a thick plate with small width can be selected for forming, and the maximum size of part forming can be improved.

Drawings

FIG. 1 is a schematic view of an aircraft engine annular lip component.

Fig. 2 is a schematic view of a first step of spin forming.

FIG. 3 is a schematic view of a process element.

Fig. 4 is a schematic diagram of the second step bulging.

The numbering in the figures illustrates: 1 lip inner ring, 2 lip outer ring, 3 lip model edge line, 4 spinning wheel, 5 annular thick plate, 6 spinning tire, 7 flange face, 8 revolution curved surface, 9 engine lip process piece, 10 blank holder, 11 bearing block, 12 concave die, 13 flange face, 14 liquid medium, 15 liquid filling port, 16 liquid discharging port.

Detailed Description

As shown in FIGS. 1-4, in this embodiment, the annular lip part has an outer diameter of 1810mm, an inner diameter of 1420mm, a material thickness of 1.2mm, and a lip part depth of 210mm, and 2A12 aluminum alloy is selected. Spinning mould includes spinning child 6 and spinning wheel 4, the flange face 7 of spinning child 6 can set up in the coplanar according to the lip model, two spinning wheels 4 are located annular lip inner circle 1 and lip outer lane 2 respectively, two spinning wheels 4 can realize concerted movement, bulging mould includes die 12, blank holder 10, liquid filling port 15, the leakage fluid dram 16, bearing block 11, liquid filling port 15 sets up in blank holder 10 rounding off district intermediate position, leakage fluid dram 16 sets up in die 12 centre of gyration position, bearing block 11 sets up in the both sides of engine lip process spare 9 flange face 7, along die 12 gyration axis evenly distributed, the forming method includes following step:

1, constructing a molding surface of a spinning die: the blank is an annular thick plate 5, the molded surface of the spinning die comprises a flange surface 7, a revolution surface 8 and a transition part of the flange surface 7 and the revolution surface 8, wherein the normal section size of the revolution surface 8 is smaller than the minimum size of the normal section of the annular lip model, and the revolution central axis of the part is determined according to the projection surface of the annular lip model. The minimum width section of the lip part is measured and determined in a plane passing through a revolution axis, the minimum width section is shifted along a normal direction, a shifted curve rotates along the revolution axis, the envelope of a revolution curved surface 8 in an annular lip model is ensured by controlling the shift of the minimum width section, a flange surface 7 is expanded to the normal direction through an edge external extension line of the revolution curved surface 8, smooth transition is adopted between the revolution curved surface 8 and the annular flange surface 7, and a constructed process molded surface is used as a spinning mold surface.

2, constructing a female die molded surface of the bulging die: the flange surface 13 of the die 12 is a plane structure, the flange surface 13 is constructed according to the extrapolation extension line of the lip model edge line 3 along the normal direction of the rotation central axis, the flange surface 13 and the flange surface 7 are in the same plane, and the smooth transition is adopted between the flange surface 13 and the outer surface of the lip model, so that the die 12 is constructed.

3, constructing a blank holder pressing surface: the pressing surfaces of the blank holder 10 are obtained by offsetting flange surfaces 13 of the molded surface of the female die 12, and smooth transition is adopted among the pressing surfaces;

and 4, manufacturing the spinning die by using the molded surface of the constructed spinning die.

5, manufacturing an expansion female die 12 by using the structural expansion female die molded surface, and manufacturing a blank holder 10 by using the structural blank holder pressed surface.

6 according to the spinning die manufactured, a standard revolving body engine lip process piece 9 is formed in a spinning mode that the inner side and the outer side of an annular lip are simultaneously spun, spinning grains exist on the surface of the process piece 9 after spinning, the surface quality of the lip part is affected, the spinning grains can be processed through machining modes such as polishing and finish turning, meanwhile, in order to further improve the strength of the lip part, the process piece 9 after spinning is subjected to heat treatment, and the internal stress is eliminated. The number of the spinning wheels 4 is 2 during spinning forming, the spinning wheels are respectively positioned on the inner ring and the outer ring of the annular lip part, and the 2 spinning wheels 4 can act in a synergistic manner and spin the inner ring and the outer ring of the annular lip part at the same time.

7 according to the manufactured bulging female die 12, bulging the formed rotary body engine lip process part 9 to the required shape radian of the lip part by adopting a liquid medium 14 bulging mode.

And 8, cutting the expanded part along the contour line of the lip part to obtain the final contour of the engine lip part.

The above description is a specific embodiment 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.