Pouring system of multi-layer separated-cavity aircraft engine main engine box

Abstract

The utility model discloses a pouring system of a multi-layer separated-cavity aircraft engine main engine box, the upper end of a pressure regulating gate is connected with the circle center of a round-cake-shaped cross gate, a plurality of sprues are uniformly arranged at the center of the upper end face of the round-cake-shaped cross gate, and the sprues are respectively connected with the inner wall of an upper flange through inner gates; a plurality of inner circumference lower sprues are arranged on the circumference of the middle part of the cake-shaped cross gate and are connected with the circumference of the bottom of the casing shell; a plurality of peripheral lower sprues connected with the bottom circumference of the lubricating oil tank are arranged on the outer circumference of the upper end surface of the cake-shaped cross gate; two passing cylinders are connected to the peripheral wall of the cake-shaped cross gate, the top of each passing cylinder is connected with the periphery of the annular cross gate through a radial inner flow pouring gate, a plurality of radial outer flow pouring gates are connected to the periphery of the annular cross gate, and the inner side of the bottom of each radial outer flow pouring gate is connected with the outer end face of the lower flange through an inner side upper pouring gate. The system can simultaneously meet the pouring requirements of thick and large parts and partition cavity thin-wall parts in the multi-layer partition cavity magnesium alloy casting.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of casting systems, especially a kind of pouring system of multilayer cavity aircraft engine main case, belong to magnesium alloy casting technical field. BACKGROUND

[0002] As an indispensable part of aviation equipment, aircraft engine is the decisive factor of aircraft performance, reliability and cost, and its technical development plays an extremely important role in national defense and national economy. The main load-bearing part of the engine is the case, which has complex structure, high design difficulty, complex production process and relatively long production cycle. Therefore, the design and production efficiency of the engine case account for a large proportion of the development of this engine. With the rapid development of China's aviation industry, there is an increasing demand for lightweight, integrated and multifunctional cases, and the structure design is becoming more and more complex. It has become a trend to replace aluminum alloy with magnesium alloy. Currently, the mainstream engine main case is still mainly made of aluminum alloy, and the design structure is relatively simple. It is still a big problem to cast complex thin-walled cases with magnesium alloy, not only because magnesium is easy to burn and has high safety risk, but also because the qualified rate is low, the cost is high, and the cycle is long.

[0003] The engine main case casting has complex structure, with five layers of cavity. It is difficult to pour and form complex cavities, and the casting difficulty is extremely great. The traditional blades are solid blades, and the blades of the new case casting are all hollow blades. The traditional mold sand type is difficult to make, easy to break and deform, and has extremely poor casting process. Similar castings are usually made by mold, which has high production cost and long production cycle. Compared with other sand castings, the engine main case casting has very high requirements for size accuracy and surface roughness.

[0004] In addition, many non-machining surfaces of the engine main case casting cannot be connected to the sprue or placed with risers for feeding. If cold iron is placed on the non-machining surface, the surface roughness of the casting cannot meet the requirements of the design drawing. SUMMARY

[0005] The purpose of this section is to outline some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract of the specification and the utility model name, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0006] In view of the above and / or problems existing in the prior art, the utility model is proposed.

[0007] The utility model discloses a purpose at, overcome the problem in prior art, provide a kind of pouring system of multilayer cavity aircraft engine main casing, can simultaneously satisfy the pouring requirement of thick part and cavity thin wall part in multilayer cavity magnesium alloy casting, avoid air retention and non-machining surface shrinkage, realize the sequential solidification of casting, reliable and avoid pouring insufficient, improve casting quality.

[0008] To solve above technical problem, a kind of pouring system of multilayer cavity aircraft engine main casing of the utility model, aircraft engine main casing includes circular machine casing, the lower port of machine casing is equipped with lower flange, the lower outer circumference of machine casing is equipped with lubricating oil tank, the upper center of machine casing is equipped with the center tube extending upwards, the upper portion of center tube exceeds machine casing and is equipped with upper flange, the annular space between the lower outer wall of center tube and the upper inner wall of machine casing is connected by multiple hollow blades as a whole;The upper end of pressure regulating sprue is connected with the center bottom of round-pie-shaped cross sprue, the center of the upper end surface of round-pie-shaped cross sprue is evenly provided with multiple straight sprues extending upwards with concentric circles, the outer wall of each straight sprue is connected with the inner wall of the upper flange through straight sprue inner gate respectively;The upper end surface of round-pie-shaped cross sprue is evenly provided with multiple inner circumferential lower gates on the middle circumference, and the bottom circumference of the machine casing is connected;The upper end surface of round-pie-shaped cross sprue is evenly provided with multiple outer circumferential lower gates on the outer circumference, and the bottom circumference of the lubricating oil tank is connected;The outer wall of the round-pie-shaped cross sprue is connected with at least two upward extending through tubes, the top of each through tube is connected with the outer circumference of annular cross sprue through radial inner flow gate respectively, and the outer circumference of the annular cross sprue is connected with multiple radial outer flow gates, and the bottom inner side of each radial outer flow gate is connected with the outer end surface of the lower flange through inner side upper gate respectively.

[0009] Further, the outer wall of the lubricating oil tank is provided with multiple bosses, and the inner side wall of each through tube is connected with the corresponding boss through a through tube inner gate.

[0010] Further, one end of the inner cavity space of each hollow blade is connected with the lower cavity of the center tube, and the other end is connected with the annular cavity in the upper thin wall of the machine casing.

[0011] Further, the hot section of the engine main casing is provided with chills respectively, and the surface of each chill facing the non-machining surface of the casting is covered with a 5-8mm thick sand layer.

[0012] Further, the bottom of the center tube is provided with a center tube inner step with an expanded diameter, the outer circumference of the center tube inner step is evenly provided with multiple exhaust holes, each exhaust hole extends upwards and is higher than the top of the annular cross sprue.

[0013] With respect to the prior art, the utility model has obtained the following beneficial effects: 1, set the anti gravity pressure pouring mode, metal liquid flows under pressure, and the filling capacity is relatively improved, can provide stable adjustable flow rate and pressure, guarantees each separate cavity to pour full, obtains the compact organization, and the whole castings crystallize under pressure environment, has no pinhole and shrinkage porosity defect;

[0014] 2, the bottom adopts the whole big plane round cake shape ingate, on the one hand is favorable to alloy liquid filling when stable, on the hand increases the cross section area and can guarantee that all ingates are liquid simultaneously;The design of upper and lower horizontal gates can simultaneously supplement the castings from the upper and lower sides, increase the overall pressure, improve the supplementing effect, simultaneously reduce the heat node brought by traditional riser;

[0015] 3, the over cylinder design is in the outside one hand plays the role of connecting upper and lower horizontal gates, on the other hand according to the characteristics of product structure, set up point gate on it, supplement the thick side wall position.Multiple ingate design plays the role of stabilizing flow rate, directly connects horizontal gate, pressure is sufficient, improves the supplementing effect;Can directly supplement each thick position and each separate cavity, also can reduce the size of ingate, avoid the generation of large heat node, improve product quality;

[0016] 4, the design of exhaust hole one hand plays the role of exhaust, reduces the generation of blowhole type defects, on the other hand plays the role of slag collection, solves the problem of magnesium alloy castings gas retention and non machining surface shrinkage;The sand cooling of cold iron can improve the surface roughness and dimensional accuracy of castings, and the dimensional tolerance of castings is ±0.37mm, and the surface roughness is less than or equal to 3.2um. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the following will briefly introduce the drawings needed to be used in embodiment description, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without paying the creative labor, and the drawings are only provided for reference and illustration, not to limit the utility model. Among them:

[0018] Figure 1 It is the front view of the aircraft engine main case casting in the utility model;

[0019] Figure 2 It is the front view of the aircraft engine main case casting in the utility model; Figure 1 ;

[0020] Figure 3 It is the front view of the aircraft engine main case casting in the utility model; Figure 2 ;

[0021] Figure 4The utility model discloses an aircraft engine main casing casting upside-down stereogram;

[0022] Figure 5 The utility model discloses a multilayer compartment aircraft engine main casing's pouring system's perspective drawing;

[0023] Figure 6 The utility model discloses a multilayer compartment aircraft engine main casing's pouring system's front view;

[0024] Figure 7 For Figure 6 The top view;

[0025] In the drawing: 1. aircraft engine main casing;1a. upper flange;1b. center tube inner step;1c. hollow blade;1d. lower flange;1e. lubricating oil tank;1f. mounting seat;1g. support lug;1h. oil tank oil inlet;1j. oil tank oil outlet;

[0026] 2. pressure regulating gate;3. round cake shape cross runner;4. straight runner;5. straight runner inner gate;6. inner periphery lower gate;7. outer periphery lower gate;8. pass through cylinder;9. pass through cylinder inner gate;10. radial inner runner;11. annular cross runner;12. radial outer runner;13. inner side upper gate;14. outer side upper gate;15. exhaust hole;16. chill. DETAILED DESCRIPTION

[0027] In the following description of the utility model, the orientation or position relation indicated by the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer" and the like is based on the orientation or position relation shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and does not mean that the device must have a particular orientation.

[0028] In order to make the technical means, creative features, purposes and effects realized by the utility model easy to understand, the utility model is further described below in combination with specific drawings. Obviously, the described embodiments are only a part of the embodiments of the utility model, not all the embodiments.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the utility model belongs. The terms used in the specification of the utility model are only for the purpose of describing specific embodiments and are not intended to limit the utility model.

[0030] As Figures 1 to 3As shown, the multi-layer cavity aircraft engine main casing of the utility model comprises a circular casing shell, the lower end of the casing shell is provided with a lower flange 1d, the lower part of the casing shell is integrated with a lubricating oil cavity to form a lubricating oil tank 1e covering the lower part of the casing shell, the outer wall of the lubricating oil tank 1e is provided with a mounting seat 1f, a lug 1g, an oil inlet 1h and an oil outlet 1j and the like, thereby forming a plurality of outer bosses on the outer wall of the lubricating oil tank 1e.

[0031] The upper part of the center of the casing shell is provided with a center cylinder extending upward, the upper part of the center cylinder exceeds the casing shell and is provided with an upper flange 1a, and the lower end of the center hole of the center cylinder is provided with a center cylinder inner step 1b with an expanded diameter. The annular space between the lower part of the outer wall of the center cylinder and the inner wall of the upper part of the casing shell is connected by a plurality of hollow blades 1c to form an integral whole. One end of the inner cavity space of each hollow blade 1c is connected with the lower cavity of the center cylinder, and the other end is connected with the annular cavity in the thin wall of the upper part of the casing shell.

[0032] As shown, Figures 4 to 7 When pouring, the engine main casing is inverted, that is, the upper flange 1a is located at the lower end, and the lower flange 1d is located at the upper end.

[0033] The lower part of the upper flange 1a is provided with a round cake-shaped cross gate 3, the bottom center of the round cake-shaped cross gate 3 is provided with a pressure regulating gate 2, the upper end surface of the round cake-shaped cross gate 3 is uniformly provided with seven upward extending straight gates 4 in concentric circles, and the outer wall of each straight gate 4 is connected with the inner wall of the upper flange 1a through a straight gate inner gate 5.

[0034] A plurality of inner circumferential lower gates 6 are uniformly arranged on the middle part of the upper end surface of the round cake-shaped cross gate 3 and connected with the bottom circumference of the casing shell; a plurality of outer circumferential lower gates 7 are uniformly arranged on the outer circumferential surface of the upper end surface of the round cake-shaped cross gate 3 and connected with the bottom circumference of the lubricating oil tank 1e.

[0035] The outer wall of the round cake-shaped cross gate 3 is connected with at least two upward extending through cylinders 8, the inner wall of each through cylinder 8 is connected with the corresponding boss through a through cylinder inner gate 9; the top of each through cylinder 8 is connected with the outer circumference of an annular cross gate 11 through a radial inner flow gate 10, the outer circumference of the annular cross gate 11 is connected with a plurality of radial outer flow gates 12, the bottom inner side of each radial outer flow gate 12 is connected with the outer end surface of the lower flange 1d through an inner side upper gate 13, and the bottom outer side of each radial outer flow gate 12 is connected with the corresponding boss through an outer side upper gate 14.

[0036] The molten magnesium alloy liquid flows upward from the pressure regulating gate 2 into the round cake-shaped cross gate 3, the magnesium alloy liquid in the central area of the round cake-shaped cross gate 3 flows upward along each straight gate 4, and fills the upper flange 1a part through each straight gate inner gate 5.

[0037] The larger plane of the disc-shaped horizontal runner 3 allows the liquid to rise synchronously from each sprue 4, each inner circumferential gate 6, each outer circumferential gate 7, and the transom 8. The inner circumferential gate 6 fills the bottom circumference of the casing, and the outer circumferential gate 7 fills the bottom circumference of the lubricating oil tank 1e. At the same time, the magnesium alloy liquid rises to the top through the two transoms, enters the annular horizontal runner 11 along the radial inner runner 10, and then enters each radial outer runner 12 from the annular horizontal runner 11. Each radial outer runner 12 fills the circumference of the lower flange 1d through the inner upper gate 13, and the inner gate 9 and outer upper gate 14 of the transom fill the boss.

[0038] The anti-gravity casting method is used to enhance the fluidity of the solution, improve the filling capacity, ensure that each cavity is filled, and allow the casting to crystallize and solidify under pressure, resulting in a denser structure and preventing the formation of defects such as porosity and shrinkage.

[0039] Multiple chills 16 are evenly spaced on the circumference of the lower flange 1d, spaced apart from the inner upper gate 13; chills 16 are also placed on hot spots such as bosses on the outer periphery of the casting. For the machined surfaces of the casting, the chills 16 can be in close contact with the casting to enhance the chilling effect and improve the internal quality of the casting.

[0040] Magnesium alloys are easily combustible and generate a large amount of gas. Combined with the large amount of gas produced during traditional sand casting, this can easily lead to gas trapping. The bottom of the center cylinder has an enlarged inner step 1b, and multiple vent holes 15 are evenly distributed along the outer periphery of the inner step 1b. Each vent hole 15 extends upwards and is higher than the top of the annular horizontal runner, guiding the gas out and reducing gas trapping, thus significantly improving the product yield.

[0041] The thin-walled sections of this main casing casting are mostly unmachined surfaces. The overall structure is only 3mm thick, and the dimensional tolerance is only allowed within ±0.5mm. Furthermore, the surface roughness of the unmachined surfaces must be less than 3.2μm, which presents very high design requirements and challenges.

[0042] In conventional methods, the chill is placed close to the casting, resulting in a relatively rough surface. Due to the high surface roughness and dimensional tolerance requirements of this main casing casting, the surface of this casting cannot be placed close to the chill and gate.

[0043] However, shrinkage porosity will occur if the gate and chill are not placed. Therefore, the following technical solution is adopted: placing a steel or iron chill with strong cooling effect in the sand layer, with a sand layer 5-8mm away from the non-machined surface of the casting, can not only play the role of cooling and heat absorption to prevent shrinkage porosity, but also ensure the size and surface roughness of the product and prevent shrinkage porosity from occurring.

[0044] By adopting the way of vacuum, the exhaust pipeline is designed in advance on the 3D sand mold, the cold iron groove is designed between the casting cavity and the sand mold, through the comparison of test, the shrinkage is reduced by 1 / 2, the problems of gas retention and shrinkage of non-machining surface of magnesium alloy castings are completely solved.

[0045] The above only describes the preferred embodiments of the present application, and shows and describes the basic principles, main features and advantages of the present application, and does not limit the patent protection scope of the present application. It should be understood by those skilled in the art that the present application is not limited by the above embodiments. In addition to the above embodiments, other embodiments of the present application can be provided without departing from the spirit and scope of the present application. The present application can also have various changes and improvements. Any technical solution formed by equivalent replacement or equivalent transformation falls within the scope of protection required by the present application. The scope of protection required by the present application is defined by the appended claims and their equivalents. The technical features not described in the present application can be realized by or using the existing technology, and will not be described here.

Claims

1. A multiple layer, cavity walled, aircraft engine main housing casting system, characterized by: The engine main casing of the aircraft comprises a circular casing shell, the lower end of the casing shell is provided with a lower flange, the lower outer circumference of the casing shell is provided with a lubricating oil tank, the upper center of the casing shell is provided with a center cylinder extending upward, the upper part of the center cylinder exceeds the casing shell and is provided with an upper flange, and the annular space between the lower outer wall of the center cylinder and the upper inner wall of the casing shell is connected into one by a plurality of hollow blades. The upper end of the pressure regulating gate is connected with the center bottom of the circular cake-shaped cross gate, a plurality of straight gates extending upward are uniformly arranged on the center of the upper end surface of the circular cake-shaped cross gate in a concentric circle, and the outer walls of the straight gates are respectively connected with the inner walls of the upper flanges through straight gate inner gates. A plurality of inner circumferential lower gates are uniformly arranged on the upper end surface of the circular cake-shaped cross gate, and the lower gates are connected with the bottom circumferences of the casing shells. The outer circumferential walls of the circular cake-shaped cross gates are connected with at least two upward extending through cylinders, the top parts of the through cylinders are respectively connected with the outer circumferences of the annular cross gates through radial inner flow gates, the outer circumferences of the annular cross gates are connected with a plurality of radial outer flow gates, and the bottom inner sides of the radial outer flow gates are respectively connected with the outer end surfaces of the lower flanges through inner side upper gates.

2. The multiple layer cavity muff system of claim 1 wherein: The outer walls of the lubricating oil tanks are provided with a plurality of bosses, the inner walls of the through cylinders are connected with the corresponding bosses through through cylinder inner gates, and the bottom outer sides of the radial outer flow gates are respectively connected with the corresponding bosses through outer side upper gates.

3. The multiple layer cavity muff for an aircraft engine of claim 1 wherein: One end of the inner cavity space of each hollow blade is connected with the lower cavity of the center cylinder, and the other end is connected with the annular partition cavity in the upper thin wall of the casing shell.

4. The multiple cell aircraft engine main housing casting system of claim 1 wherein: The hot section of the engine main casing is respectively provided with a cold iron, and the surface of each cold iron facing the non-machining surface of the casting is respectively covered with a 5-8mm thick sand layer.

5. The multi-layered cell phone case of claims 1 to 4, wherein: The bottom of the center cylinder is provided with a center cylinder inner step with an expanded diameter, the outer circumference of the center cylinder inner step is uniformly provided with a plurality of exhaust holes, and each exhaust hole extends upward and is higher than the top of the annular cross gate.

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