Cavity runner wax filling method

Abstract

The present application discloses a method for wax filling a mold cavity flow channel, comprising the following steps: placing a sleeve in the mold cavity flow channel of a workpiece, forming a wax filling cavity between the sleeve and the mold cavity flow channel, and forming a cooling cavity in the sleeve; injecting liquid wax into the wax filling cavity, the wax being injected multiple times, each wax injection forming a wax filling layer in the wax filling cavity, each wax filling layer covering the independent components in the mold cavity flow channel, and the injection interval between adjacent wax filling layers being a preset time; injecting coolant into the cooling cavity; and separating the sleeve and the workpiece after the wax in the wax filling cavity solidifies. The present application has the advantages of preventing fine sand from leaking, preventing the workpiece from being damaged by the entry of fine sand during the wax filling process, and shortening the working time of the wax filling process.

Description

Technical Field

[0001] The invention relates to the technical field of processing half casing components, in particular to a wax filling method for a cavity flow channel. Background Art

[0002] The half-casing assembly is a key component of a turboshaft engine. Its working principle is that the guide vanes and stator rings assembled on the half-casing work together with the rotor to provide compressed air to the combustion chamber. To ensure that the air compression ratio meets the engine's operating requirements, the clearance tolerance between the guide vane tips, the stator ring tips, and the wear-resistant coating on the rotor is generally around 0.1mm. To ensure the required clearance, the half-casing requires the blade tips to be ground after assembling the guide vanes and stator rings. Since the blades are all cantilever beam structures with poor rigidity, to ensure machining accuracy, the casing generally needs to be waxed before grinding to coat the blades with a wax layer and increase rigidity.

[0003] Reference Figure 1 At present, the wax filling process of the half receiver of each model adopts a simple tool made of foam board 10 and sandbags to fill the wax, such as Figure 1 As shown, a simple bottom plate is first made of foam pads to block the exhaust edge of the axial flow casing. A transparent plastic bag 9 is then placed inside the casing. Fine sand is then filled into the plastic bag 9 to fill the inner cavity, forming a sandbag and serving as a sand core. Finally, cooled yellow wax is poured into the wax filling area in batches. The current wax filling method has the following main problems: The current wax filling process involves pouring liquid wax into the wax filling area after filling the sand core. During this process, if the wax temperature is too high, the high temperature can easily melt the sand-filled plastic bag, causing the sand core to leak. Summary of the Invention

[0004] The invention provides a method for wax filling of a mold cavity flow channel, which solves the technical problem that wax filling using a sand core in the prior art easily causes leakage of the sand core and thus causes fine sand to enter a workpiece.

[0005] According to one aspect of the present invention, a method for wax filling a mold cavity runner is provided, comprising the following steps:

[0006] A metal sleeve is placed in the cavity flow channel of the workpiece to form a wax filling cavity between the sleeve and the cavity flow channel, and a cooling cavity is formed in the sleeve; liquid wax is injected into the wax filling cavity, and the wax is injected in multiple times. Each wax injection forms a wax filling layer in the wax filling cavity, and each wax filling layer covers the independent components in the cavity flow channel respectively. The injection interval of adjacent wax filling layers is preset time; coolant is injected into the cooling cavity; after the wax in the wax filling cavity solidifies, the sleeve and the workpiece are separated.

[0007] By adopting the above technical solution, on the one hand, a sleeve is placed within the cavity flow channel to form a wax filling cavity. Wax only needs to be poured into the wax filling cavity, which can effectively reduce the volume of wax filling and improve wax filling efficiency. At the same time, compared to the sand core method, this solution will not leak fine sand during operation, so that the workpiece will not be damaged by fine sand entering during the wax filling process. On the other hand, injecting coolant into the inner cavity of the sleeve can accelerate the cooling of the liquid wax, thereby shortening the working time of the wax filling process. Each layer of wax filling separately covers the independent components within the cavity flow channel, so that the precision components within the workpiece cavity flow channel can be covered by the same wax filling layer, without crossing multiple wax filling layers, avoiding deformation of the precision components due to inconsistent cooling stages of different wax filling layers.

[0008] Optionally, the injecting of coolant into the cooling cavity comprises the following steps: the coolant is injected in multiple times, and the coolant is injected once after each wax filling layer is injected, and the height of the coolant in the cooling cavity corresponds to the thickness of the wax filling layer.

[0009] By adopting the above technical solution, the wax layer starts to solidify from the bottom. After the bottom wax layer cools and shrinks, the upper wax layer that has not yet solidified can continue to supplement the shrunken part of the lower layer, ensuring that the wax filling area is tighter and the blade fixation rigidity is stronger.

[0010] Optionally, before the step of placing the sleeve in the cavity flow channel of the workpiece, the following step is also included: placing the base at the bottom of the workpiece, and the surface of the base is adapted to the shape of the workpiece; after the step of placing the sleeve in the cavity flow channel of the workpiece, the following step is also included: connecting the base and the sleeve using a connector.

[0011] By adopting the above technical solution, the base can seal the bottom end of the workpiece cavity flow channel to prevent liquid wax from flowing out from the bottom end of the cavity flow channel. At the same time, after the base and the sleeve are connected using a connector, during the wax pouring process, the sleeve will not move due to the impact of the liquid wax, and the wax pouring process will be more stable.

[0012] Optionally, an elastic member is provided between the sleeve and the base, and during the step of injecting molten wax into the wax filling cavity, the elastic member supports the sleeve so that a gap is formed between the sleeve and the base; before the step of separating the sleeve and the workpiece, the following step is also included: moving the sleeve toward the base, compressing the elastic member, and separating the sleeve from the wax filling layer.

[0013] By adopting the above technical solution, due to the support of the elastic part, after the wax filling is completed, there is still a gap between the sleeve and the base. After the wax cools and solidifies, the sleeve can be separated from the wax by simply pressing down the sleeve until the sleeve contacts the base. The operation is relatively convenient. At the same time, due to the support of the base, the travel of the sleeve can be limited so that the sleeve will not move too far. After the downward pressure on the sleeve is released, the sleeve will be reset under the action of the elastic part.

[0014] Optionally, the connecting member includes a fastening rod, which passes through the sleeve and is threadedly connected to the base, and a pushing portion corresponding to the sleeve is provided on the fastening rod; moving the sleeve toward the base includes the following steps: rotating the fastening rod, and moving the fastening rod toward the base through the threaded cooperation between the fastening rod and the base, so that the fastening rod pushes the sleeve to move.

[0015] By adopting the above technical solution, the circumferential rotational motion is converted into the linear movement of the sleeve through threaded cooperation. On the one hand, it can generate a large thrust on the sleeve. When the sleeve is tightly adhered to the solidified wax, the sleeve can also be moved relative to the solidified wax to achieve the purpose of separating the sleeve. At the same time, the sleeve is pushed to move by threaded cooperation, which can keep the sleeve moving in a linear manner, and will not crush the solidified wax due to the displacement of the sleeve. At the same time, it can play a guiding role.

[0016] Optionally, the elastic member is a spring, a connecting rod is passed through the spring, the connecting rod is fixedly connected to the sleeve, and a connecting hole corresponding to the connecting rod is opened on the base; when the sleeve moves toward the base, the connecting rod slides in the connecting hole.

[0017] By adopting the above technical solution, when the connecting rod moves with the sleeve, the connecting hole can provide space for the movement of the connecting rod, so that the connecting rod will not collide with the base. At the same time, the connecting rod can position the spring, so that the spring can expand and contract along the connecting rod when under pressure without bending to one side, and can also play a guiding role.

[0018] Optionally, the outer wall of the sleeve is a conical surface that gradually expands from an end away from the base to an end close to the base.

[0019] By adopting the above technical solution, during the process of separating the sleeve from the solidified wax, the conical surface setting of the sleeve can effectively reduce the friction between the sleeve and the wax, and can make demoulding more labor-saving.

[0020] Optionally, the base includes a detachably connected base body and a connecting plate, the base body is provided with a sliding groove corresponding to the sleeve, the connecting plate is arranged in the sliding groove and fixedly connected to the base, the elastic member is located between the connecting plate and the sleeve, the fastening rod is threadedly connected to the connecting plate, and the connecting hole is provided on the connecting plate; in the step of moving the sleeve toward the base, the sleeve slides in the sliding groove, and the distance between the end face of the sleeve and the connecting plate gradually decreases until the sleeve contacts the connecting plate.

[0021] By adopting the above technical solution, during the assembly process of the tooling, the elastic member can be installed first and then the connecting plate can be installed on the base body, or the connecting plate can be removed from the base body after a period of use for easy inspection and maintenance.

[0022] Optionally, in the step of rotating the fastening rod, a movable handle is used to drive the fastening rod to rotate; the pushing portion is polygonal, a groove corresponding to the pushing portion is formed at one end of the movable handle, and the other end of the movable handle extends from the top of the sleeve.

[0023] By adopting the above technical solution, the push part is rotated by rotating the movable handle, thereby rotating the fastening rod, and the movable handle is extended out of the sleeve, which is convenient for staff to operate.

[0024] Optionally, before the step of injecting molten wax into the wax filling cavity, the following steps are also included: heating to melt the solid wax; and allowing the liquid wax to stand until a wax film appears on the surface of the liquid wax.

[0025] By adopting the above technical solution, when the temperature of the wax is too high, if it is directly poured into the wax filling chamber, after cooling for a period of time, the outer layer of wax solidifies, but the middle wax has not completely solidified. It is necessary to wait for the wax to completely solidify before the next wax filling. The waiting time is long, resulting in a long working time for the wax filling process. Cooling the wax first and then pouring the wax can shorten the cooling time.

[0026] In summary, this application includes at least one of the following beneficial technical effects:

[0027] 1. Compared with the sand core method, this solution will not leak fine sand during operation, so the workpiece will not be damaged by fine sand during the wax filling process;

[0028] 2. Only wax needs to be poured into the wax filling chamber, which can effectively reduce the volume of wax filling and improve the efficiency of wax filling;

[0029] 3. Injecting coolant into the inner cavity of the sleeve can accelerate the cooling of the liquid wax, thereby shortening the working time of the wax filling process.

[0030] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 It is a structural diagram of a medium-sized cavity flow channel wax filling tool in the prior art;

[0033] Figure 2 Schematic diagram of the cross-sectional structure of the cavity flow channel wax filling tooling according to the preferred embodiment of the present invention;

[0034] Figure 3 1. It is a bottom view of the mold cavity flow channel wax filling tooling of the preferred embodiment of the present invention;

[0035] Figure 4 This is a schematic structural diagram of the cooperation between the mold cavity flow channel wax filling tool and the workpiece in a preferred embodiment of the present invention;

[0036] Figure 5 It is a flow chart of the method for wax filling of the cavity runner according to the preferred embodiment of the present invention.

[0037] Legend:

[0038] 11. Base; 12. Connecting plate; 2. Sleeve; 3. Elastic member; 4. Fastening rod; 5. Movable handle; 6. Connecting rod; 7. Gasket; 8. Workpiece; 9. Plastic bag; 10. Foam board. DETAILED DESCRIPTION

[0039] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0040] The following is combined with Figure 1-5 This application is described in further detail.

[0041] The embodiment of the present application discloses a method for wax filling of a mold cavity runner.

[0042] Reference Figure 2 and Figure 3 The cavity runner wax filling method uses a cavity runner wax filling tool. The cavity runner wax filling tool includes a base and a sleeve 2. The upper surface of the base is used to support the workpiece 8, and the shape of the upper surface of the base is adapted to the shape of the workpiece 8, so that liquid wax is not easily leaked from the gap between the base and the workpiece 8. The sleeve 2 is used to be placed in the cavity runner. A cooling chamber for accommodating coolant is formed in the sleeve 2, and the bottom of the sleeve 2 is connected to the sleeve 2 via a connector. The sleeve 2 is made of metal.

[0043] The base includes a detachably connected base body 11 and a connecting plate 12. A sliding groove corresponding to the sleeve 2 is opened on the base body 11. The connecting plate 12 is arranged in the sliding groove and fixed to the base by bolts. The sleeve 2 can slide up and down in the sliding groove. When the sleeve 2 slides down to the lowest position, the upper surface of the connecting plate 12 contacts the bottom end surface of the sleeve 2 to limit the sleeve 2.

[0044] In order to facilitate the demoulding of the sleeve 2, optionally, an elastic member 3 is provided between the sleeve 2 and the base. The elastic member 3 supports the sleeve 2 so that a gap is formed between the sleeve 2 and the base. After the wax filling is completed, the sleeve 2 can be demoulded by pushing it downward. After the demoulding is completed, the sleeve 2 will be reset under the action of the elastic member 3.

[0045] The connecting member includes a fastening rod 4, which passes through the sleeve 2 and is threadedly connected to the connecting plate 12 of the base. The fastening rod 4 is provided with a pushing portion corresponding to the sleeve 2. When the fastening rod 4 is rotated, the fastening rod 4 and the pushing portion are moved toward the base through the threaded cooperation between the fastening rod 4 and the connecting plate 12, thereby causing the pushing portion to push the sleeve 2 downward. Optionally, in order to facilitate the rotation of the fastening rod 4, a movable handle 5 is used to drive the pushing portion to rotate. The pushing portion is polygonal, such as a regular hexagon or a square. A groove corresponding to the pushing portion is formed at one end of the movable handle 5, and the other end of the movable handle 5 extends from the top of the sleeve 2. The staff only needs to rotate the handle outside the sleeve 2 to drive the pushing portion to rotate, thereby rotating the fastening rod 4. Optionally, in order to improve waterproofness and prevent water from leaking from the bottom of the sleeve 2, an elastic gasket 7 is provided between the connecting rod 6 and the sleeve 2.

[0046] The elastic member 3 is a spring, in which a connecting rod 6 is passed. The connecting rod 6 is fixedly connected to the sleeve 2, and a connecting hole corresponding to the connecting rod 6 is opened on the connecting plate 12. When the sleeve 2 moves downward, the elastic member 3 is compressed and the connecting rod 6 slides in the connecting hole.

[0047] Reference Figure 4 and Figure 5 The method for wax filling of the cavity runner includes the following steps:

[0048] In step S100, the sleeve 2 is placed in the cavity flow channel of the workpiece 8 to form a wax filling cavity between the sleeve 2 and the cavity flow channel, and a cooling cavity is formed in the sleeve 2; the wax filling cavity is used for filling wax, and the cooling cavity is used for containing coolant.

[0049] Step S200, inject liquid wax into the wax filling cavity, and the liquid wax is injected in multiple times. Each time the wax is injected, a wax filling layer is formed in the wax filling cavity. Each wax filling layer covers the independent components in the cavity flow channel respectively, and the filling interval of adjacent wax filling layers is preset time; optionally, taking the wax filling of half-casing parts of an aircraft engine as an example, there are multiple layers of blades distributed from bottom to top in the cavity flow channel of the half-casing. When pouring wax, pour the liquid wax into the wax filling area at a uniform speed until the liquid wax covers the first layer of blades by 3-5mm, wait for 5-10 minutes, and then continue to wax the second layer of blades. Repeat the above operation until all blade areas are waxed and the wax layer covers the topmost blades by 3-5mm.

[0050] Liquid wax is obtained by heating and melting solid wax. Optionally, after the wax is completely melted, the wax is allowed to stand for 5-10 minutes, and wax filling is started after the liquid wax cools down until a wax film begins to appear on the wax surface. When the temperature of the wax is too high, if it is directly poured into the wax filling chamber, after cooling for a period of time, the outer layer of wax solidifies, but the middle wax has not completely solidified. It is necessary to wait for the wax to completely solidify before the next wax filling. The long waiting time results in a long working time for the wax filling process. Cooling the wax before wax filling can shorten the cooling time. Optionally, in order to ensure that the liquid wax can accurately enter the wax filling chamber during the wax filling process, in step S200, a funnel is used to guide the wax to prevent the wax from spilling outside the wax filling chamber.

[0051] Step S300: Inject coolant into the cooling chamber. Optionally, water is used, which is readily available and relatively inexpensive. Alternatively, if coolant is not added, the wax can be cooled at room temperature for 30-50 minutes, until the wax is substantially solid. Optionally, after wax injection, use a bamboo blade to gently scrape off any excess wax, leaving 1-2 mm of wax exposed at the leaf tip.

[0052] Step S400: After the wax in the wax filling chamber solidifies, the sleeve 2 and the workpiece 8 are separated.

[0053] The step S100 of placing the sleeve 2 in the cavity flow channel of the workpiece 8 to form a wax filling cavity between the sleeve 2 and the cavity flow channel includes the following steps:

[0054] Step S110, placing the base on the bottom of the workpiece 8 so that the upper surface of the base is in close contact with the bottom of the workpiece 8 to prevent leakage of the liquid wax;

[0055] Step S120 , the sleeve 2 is placed in the cavity flow channel of the workpiece 8 , so that a wax filling cavity is formed between the sleeve 2 and the cavity flow channel;

[0056] Step S130, use a connector to connect the base and sleeve 2, leaving a gap between the connector and the base; connecting the sleeve 2 to the base can make the sleeve 2 more stable after being placed in the mold cavity flow channel, and is not easy to move due to the impact of wax during wax pouring. The reserved gap is to facilitate demolding after the wax solidifies.

[0057] Step S300 of injecting coolant into the cooling chamber includes the following steps: The coolant is injected multiple times, one after each wax layer. The height of the coolant in the cooling chamber corresponds to the thickness of the wax layer. This cooling method ensures that the wax layer solidifies from the bottom. As the bottom wax layer cools and shrinks, the unsolidified wax layer above it can continue to fill the shrinkage below, ensuring a tighter wax filling area and stronger blade fixation.

[0058] After the wax in the wax filling chamber solidifies, step S400 of separating the sleeve 2 and the workpiece 8 includes the following steps:

[0059] Step S410: Move the sleeve 2 toward the base to compress the elastic member 3, so that the sleeve 2 is separated from the wax layer.

[0060] Step S420: Move the workpiece 8 with the wax filling layer upward to separate the sleeve 2 and the workpiece 8.

[0061] The step S410 of moving the sleeve 2 toward the base to compress the elastic member 3 and separate the sleeve 2 from the wax layer includes the following steps:

[0062] In step S411, the movable handle 5 is mounted on the push portion. The movable handle 5 is rotated to rotate the fastening rod 4, which in turn rotates the fastening rod 4. The fastening rod 4 is moved toward the base by the threaded engagement between the fastening rod 4 and the base, causing the fastening rod 4 to push the sleeve 2 to move. As the sleeve 2 moves toward the base, the connecting rod 6 slides in the connecting hole. Optionally, the outer wall of the sleeve 2 is a tapered surface that gradually expands from the end away from the base to the end near the base. The tapered surface of the sleeve 2 can effectively reduce the friction between the sleeve 2 and the wax, allowing for more labor-saving demolding.

[0063] In the step of moving the sleeve 2 toward the base, the sleeve 2 slides in the slide groove, and the distance between the end surface of the sleeve 2 and the connecting plate 12 gradually decreases until the sleeve 2 contacts the connecting plate 12 .

[0064] Through the above solution, the processing efficiency of the wax filling process was improved by more than 50%, while the risk of excess materials in the wax filling process was avoided, ensuring that the quality of the wax filling was well controlled.

[0065] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for wax filling of a cavity runner, characterized in that: The steps include: A sleeve (2) made of metal is placed in a cavity flow channel of a workpiece (8), so that a wax filling cavity is formed between the sleeve (2) and the cavity flow channel, and a cooling cavity is formed in the sleeve (2); Liquid wax is injected into the wax cavity in multiple injections. Each injection forms a wax layer in the wax cavity. The wax layer is distributed along the flow direction of the cavity flow channel. Each wax layer covers the independent components in the cavity flow channel. The injection interval between adjacent wax layers is preset. Inject coolant into the cooling chamber; After the wax in the wax filling cavity solidifies, the sleeve (2) and the workpiece (8) are separated; Before the step of placing the sleeve (2) in the cavity flow channel of the workpiece (8), the following steps are also included: The base is placed at the bottom of the workpiece (8), and the surface of the base is adapted to the shape of the workpiece (8) to position the workpiece (8); After the step of placing the sleeve (2) in the cavity flow channel of the workpiece (8), the following steps are also included: Connect the base and the sleeve (2) using a connector; An elastic member (3) is provided between the sleeve (2) and the base. During the step of injecting molten liquid wax into the wax filling cavity, the elastic member (3) supports the sleeve (2) so that a gap is formed between the sleeve (2) and the base. Before the step of separating the sleeve (2) and the workpiece (8), the following steps are also included: The sleeve (2) is moved in a direction close to the base to compress the elastic member (3) so as to separate the sleeve (2) from the wax filling layer.

2. The method for wax filling of a mold cavity runner according to claim 1, characterized in that: Injecting coolant into the cooling chamber comprises the following steps: The coolant is injected in multiple times, and the coolant is injected once after each wax layer is injected. The height of the coolant in the cooling cavity corresponds to the thickness of the wax layer.

3. The method for wax filling of a mold cavity runner according to claim 1, characterized in that: The connecting member comprises a fastening rod (4), the fastening rod (4) passes through the sleeve (2) and is threadedly connected to the base, and a pushing portion corresponding to the sleeve (2) is provided on the fastening rod (4); The step of moving the sleeve (2) toward the base comprises the following steps: The fastening rod (4) is rotated, and the fastening rod (4) is moved toward the base through the threaded engagement between the fastening rod (4) and the base, so that the fastening rod (4) pushes the sleeve (2) to move.

4. The method for wax filling of a mold cavity runner according to claim 3, characterized in that: The elastic member (3) is a spring, a connecting rod (6) is inserted into the spring, the connecting rod (6) is fixedly connected to the sleeve (2), and a connecting hole corresponding to the connecting rod (6) is opened on the base; During the process of the sleeve (2) moving toward the base, the connecting rod (6) slides in the connecting hole.

5. The method for wax filling of a mold cavity runner according to claim 3, characterized in that: The outer wall of the sleeve (2) is a conical surface that gradually expands from an end away from the base to an end close to the base.

6. The method for wax pouring into a mold cavity runner according to claim 4, characterized in that: The base comprises a detachably connected base body (11) and a connecting plate (12); the base body (11) is provided with a sliding groove corresponding to the sleeve (2); the connecting plate (12) is arranged in the sliding groove and fixedly connected to the base; the fastening rod (4) is threadedly connected to the connecting plate (12); and the connecting hole is provided on the connecting plate (12); In the step of moving the sleeve (2) toward the base, the sleeve (2) slides in the slide groove, and the distance between the end face of the sleeve (2) and the connecting plate (12) gradually decreases until the sleeve (2) contacts the connecting plate (12).

7. The method for wax pouring into a mold cavity runner according to claim 5, characterized in that: In the step of rotating the fastening rod (4), the fastening rod (4) is driven to rotate using a movable handle (5); The pushing portion is polygonal, one end of the movable handle (5) is formed with a groove corresponding to the pushing portion, and the other end of the movable handle (5) extends from the top of the sleeve (2).

8. The method for wax pouring into a mold cavity runner according to claim 5, characterized in that: Before the step of injecting molten liquid wax into the wax filling cavity, the following steps are also included: Heat to melt solid wax; Let the liquid wax stand until a wax film appears on the surface of the liquid wax.

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