A device and process for solving wheel hub shrinkage defects

Abstract

The present invention discloses a device and a process method for solving the shrinkage defects of wheel hubs, which relates to the technical field of wheel hubs, including wheel hub castings, inner cavity sand cores, easy-separation sheet sand cores, risers, heating riser sleeves, process subsidies, and wheel hub flanges, wherein the wheel hub flange is arranged on the outer side of the inner cavity sand core, the easy-separation sheet sand core is arranged on the upper side of the wheel hub flange, the heating riser sleeve is arranged above the easy-separation sheet sand core, and the riser is composed of a recessed portion and a riser cavity. The present invention effectively shortens the shrinkage feeding distance from the shrinkage feeding source riser to the hot node of the shrinkage feeding object casting by arranging the easy-separation sheet sand core and the process subsidy, utilizes the heating effect of the thermite in the heating riser sleeve, continuously provides heat to the molten metal in the riser, and prolongs the shrinkage feeding flow time of the molten metal in the riser, and through the coordination of the above-mentioned process measures, the most economical riser is used to fully feed the hot node of the wheel hub annular casting, thereby avoiding the occurrence of concentrated shrinkage defects.

Description

Technical Field

[0001] The present invention relates to the technical field of wheel hubs, and in particular to a device and a process method for solving shrinkage defects of wheel hubs. Background Art

[0002] Wheel hub castings are one of the automotive safety parts. Most of the products are hollow annular castings, and the structure mainly consists of flanges and upper and lower bodies. A thick and large geometric heat node is formed at the junction of the flange and the cylinder, which is often the last part of the casting to solidify. Due to the long distance of shrinkage compensation and the large demand for shrinkage molten metal, it is difficult to continuously provide the molten metal required for shrinkage compensation to the hot node using traditional sand risers, which often forms concentrated shrinkage defects at this location, affecting the effective load-bearing cross-sectional area of ​​the casting. In particular, in recent years, with the implementation of the "energy conservation and emission reduction" policy, lightweight vehicle design has become more and more common, and there are many local and isolated heat nodes in automotive parts. How to ensure the internal density of wheel hub castings through reasonable process measures is an important guarantee for vehicle driving safety. Summary of the invention

[0003] 1. Technical issues to be solved

[0004] In view of the deficiencies in the prior art, the present invention provides a device and a process method for solving the shrinkage defects of hub castings, which has the advantages of being able to solve the shrinkage defects of hub castings and ensure internal density, and solves the problems raised in the background technology.

[0005] (II) Technical solution

[0006] In order to achieve the above-mentioned purpose of being able to solve the shrinkage defects of hub castings and ensure internal density, the present invention provides the following technical solutions: a device and a process method for solving the shrinkage defects of hub castings, comprising a hub casting, an inner cavity sand core, an easy-to-seperate sand core, a riser, a heat-generating riser sleeve, a process subsidy, and a hub flange, wherein the hub casting is a rotating body, the inner cavity sand core is arranged in the center hole of the hub casting, the hub flange is arranged on the outer side of the inner cavity sand core, the easy-to-seperate sand core is arranged on the upper side of the hub flange, the heat-generating riser sleeve is arranged above the easy-to-seperate sand core, a recessed portion is provided on the top of the easy-to-seperate sand core, a riser cavity matched with the recessed portion is provided below the heat-generating riser sleeve, the riser is composed of the recessed portion and the riser cavity, the process subsidy is arranged at the corner of the hub casting and the hub flange, and the process subsidy is matched with the easy-to-seperate sand core.

[0007] Preferably, the easy-to-isolate sand core is arranged at a position close to the hub flange thermal junction, the easy-to-isolate sand core is not in contact with the thermal junction, and a balanced solidification riser is arranged.

[0008] Preferably, the interior of the exothermic riser sleeve is filled with thermite, and the interior of the riser is filled with molten metal.

[0009] Preferably, an annular groove is provided on the inner wall of the wheel hub casting, the cross section of the annular groove is stepped, and the top wall thickness of the wheel hub casting is greater than the bottom wall thickness of the wheel hub casting.

[0010] Preferably, the position, shape and size of the process subsidy are adapted to the structure of the hub casting and the size of the hot spot.

[0011] A process method for solving wheel hub shrinkage defects, comprising: a wheel hub casting is arranged outside an inner cavity sand core, a riser is arranged between an easy-to-seperate sand core and a heat-generating riser sleeve, the position, shape and size of the process subsidy are matched and arranged according to the actual structure and the size of the heat node, and the heat-generating riser sleeve is fixed by interference fit with the sand tire or by inserting steel nails into the sand tire;

[0012] The molten iron is introduced into the mold cavity from the flange through the dispersed inner runner. During the pouring process, the molten iron first enters the riser cavity inside the heating riser sleeve, and then overflows through the process subsidy. In the process, the high-temperature molten metal enters the heating riser sleeve to ignite the heating riser sleeve, causing the thermite in the heating riser sleeve to react exothermically, continuously replenishing heat to the molten metal in the riser, and at the same time continuously providing liquid metal for shrinkage compensation to the hot section of the hub casting to replenish the volume vacancy caused by the solidification shrinkage of the hot section.

[0013] Three beneficial effects

[0014] Compared with the prior art, the present invention provides a device and a process method for solving the shrinkage defect of hubs, which has the following beneficial effects:

[0015] The device and process method for solving the shrinkage defects of hubs effectively shorten the shrinkage feeding distance from the shrinkage feeding source riser to the hot spot of the shrinkage feeding object casting by arranging the easy-separation sand core and the process subsidy, and continuously provide heat to the molten metal in the riser by utilizing the heating effect of the thermite in the heating riser sleeve, thereby prolonging the shrinkage feeding flow time of the molten metal in the riser; through the coordination of the above process measures, the hot spot of the hub annular casting is fully fed with the most economical riser, thereby avoiding the occurrence of concentrated shrinkage defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the cross-sectional structure of the present invention.

[0017] In the figure: 1. wheel hub casting; 2. inner cavity sand core; 3. easy-to-spacer sand core; 4. riser; 5. exothermic riser sleeve; 6. process allowance; 7. wheel hub flange. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] See also Figure 1 A device and a process method for solving the shrinkage defects of wheel hubs include a wheel hub casting 1, an inner cavity sand core 2, an easy-to-spacer sand core 3, a riser 4, a heat-generating riser sleeve 5, a process subsidy 6, and a wheel hub flange 7, characterized in that: the wheel hub casting 1 is a rotating body, the inner wall of the wheel hub casting 1 is provided with an annular groove, the cross section of the annular groove is a stepped type, the top wall thickness of the wheel hub casting 1 is greater than the bottom wall thickness of the wheel hub casting 1, the inner cavity sand core 2 is arranged in the center hole of the wheel hub casting 1, the wheel hub flange 7 is arranged on the outer side of the inner cavity sand core 2, the easy-to-spacer sand core 3 is arranged on the upper side of the wheel hub flange 7, and the easy-to-spacer sand core 3 is arranged near the heat junction of the wheel hub flange 7 The position of the easy-separator sand core 3 is that the easy-separator sand core 3 is not in contact with the hot node, and a balanced solidification riser is used. The heat-generating riser sleeve 5 is arranged above the easy-separator sand core 3, and a recessed portion is provided on the top of the easy-separator sand core 3. A riser cavity matching the recessed portion is provided below the heat-generating riser sleeve 5. The riser 4 consists of a recessed portion and a riser cavity. The interior of the heat-generating riser sleeve 5 is filled with thermite, and the interior of the riser 4 is filled with molten metal. The process subsidy 6 is arranged at the corner of the hub casting 1 and the hub flange 7. The process subsidy 6 is matched with the easy-separator sand core 3. The position, shape and size of the process subsidy 6 are matched with the structure of the hub casting 1 and the size of the hot node.

[0020] The hub casting 1 is arranged outside the inner cavity sand core 2, the riser 4 is arranged between the easy-to-isolate sand core 3 and the heat-generating riser sleeve 5, the position, shape and size of the process subsidy 6 are matched and set according to the actual structure and the size of the heat node, and the heat-generating riser sleeve 5 is fixed by interference fit with the sand tire or by inserting steel nails into the sand tire;

[0021] The molten iron is introduced into the mold cavity from the flange through the dispersed inner runner. During the pouring process, the molten iron first enters the riser cavity inside the heating riser sleeve 5, and then overflows through the process subsidy 6. In the process, the high-temperature molten metal enters the heating riser sleeve 5 to ignite the heating riser sleeve 5, so that the thermite in the heating riser sleeve 5 undergoes an exothermic reaction, and heat is continuously added to the molten metal in the riser 4. At the same time, liquid metal for shrinkage compensation is continuously provided to the hot node part of the hub casting 1 to supplement the volume vacancy caused by the solidification shrinkage of the hot node.

[0022] In summary, the device and process method for solving the shrinkage defects of hubs effectively shorten the shrinkage feeding distance from the shrinkage feeding source riser 4 to the hot node of the shrinkage feeding object casting by setting the easy-to-isolate sand core 3 and the process subsidy 6, and continuously provide heat to the molten metal in the riser 4 by utilizing the heating effect of the thermite in the heating riser sleeve 5, thereby extending the shrinkage feeding flow time of the molten metal in the riser 4; through the coordination of the above-mentioned process measures, the hot node of the hub annular casting is fully fed with the most economical riser 4, thereby avoiding the occurrence of concentrated shrinkage defects.

[0023] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise one" do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0024] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for solving the shrinkage defect of a wheel hub, comprising a wheel hub casting (1), an inner cavity sand core (2), an easy-to-seperate sand core (3), a riser (4), a heat-generating riser sleeve (5), a process subsidy (6), and a wheel hub flange (7), characterized in that: The wheel hub casting (1) is a rotating body, the inner cavity sand core (2) is arranged in the center hole of the wheel hub casting (1), the wheel hub flange (7) is arranged on the outer side of the inner cavity sand core (2), the easy-to-break sand core (3) is arranged on the upper side of the wheel hub flange (7), the heat-generating riser sleeve (5) is arranged above the easy-to-break sand core (3), a recessed portion is provided on the top of the easy-to-break sand core (3), a riser cavity matching the recessed portion is provided below the heat-generating riser sleeve (5), the riser (4) is composed of the recessed portion and the riser cavity, the process subsidy (6) is arranged at the corner between the wheel hub casting (1) and the wheel hub flange (7), and the process subsidy (6) is matched with the easy-to-break sand core (3); The easy-to-isolate sand core (3) is arranged at a position close to the heat junction of the hub flange (7), the easy-to-isolate sand core (3) is not in contact with the heat junction, and a balanced solidification riser is arranged; The interior of the exothermic riser sleeve (5) is filled with thermite, and the interior of the riser (4) is filled with molten metal; The position, shape and size of the process subsidy (6) are adapted to the structure and the size of the heat node of the wheel hub casting (1); A process method for solving wheel hub shrinkage defects based on the above device: the wheel hub casting (1) is arranged on the outside of the inner cavity sand core (2), the riser (4) is arranged between the easy-to-isolate sand core (3) and the heat-generating riser sleeve (5), the position, shape and size of the process subsidy (6) are matched and set according to the actual structure and the size of the heat node, and the heat-generating riser sleeve (5) is fixed by interference fit with the sand tire or by inserting steel nails into the sand tire; The molten iron is introduced into the mold cavity from the flange through the dispersed inner runner. During the pouring process, the molten iron first enters the riser cavity inside the heating riser sleeve (5), and then overflows through the process subsidy (6). During the process, the high-temperature molten metal enters the heating riser sleeve (5) to ignite the heating riser sleeve (5), causing the thermite in the heating riser sleeve (5) to react exothermically, continuously replenishing heat to the molten metal in the riser (4), and at the same time continuously providing liquid metal for shrinkage compensation to the hot section of the hub casting (1), thereby replenishing the volume vacancy caused by the solidification and shrinkage of the hot section.

2. The device for solving the shrinkage defect of wheel hub according to claim 1, characterized in that: The inner wall of the wheel hub casting (1) is provided with an annular groove, the cross section of the annular groove is stepped, and the top wall thickness of the wheel hub casting (1) is greater than the bottom wall thickness of the wheel hub casting (1).

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