Calendering die for heat shield of heat pipe of automobile exhaust system

Abstract

In order to solve the problems of the existing calendering method of the heat shield of the heat pipe of the automobile exhaust system, such as the need for multiple calendering or stamping and the easy occurrence of twisting deformation or warping deformation, the utility model proposes a calendering die for the heat shield of the heat pipe of the automobile exhaust system, including a calendering lower die and a calendering upper die; characterized in that drawing ribs with the same direction as the edge of the forming part are respectively arranged on both sides of the forming part of the calendering die, that is, a slender lower die groove with the same direction as the edge of the main forming part is respectively arranged on both sides of the calendering lower die forming part, and a slender upper die protrusion is respectively arranged on both sides of the calendering upper die forming part, and the position, length and direction of the upper die protrusion match the lower die groove. The beneficial technical effect of the utility model is that before the calendering blank forming part begins to deform, the two sides are fixed, so that the deformation is more uniform; at the same time, the deformation amount of each pass can be increased, and the number of calendering or stamping times can be reduced.

Description

Technical Field

[0001] The utility model relates to a calendering technology for a heat insulation cover of a heat dissipation pipe of an automobile exhaust system, in particular to a calendering die for a heat insulation cover of a heat dissipation pipe of an automobile exhaust system. Background Art

[0002] The heat shield of the heat dissipation pipe of the automobile exhaust system is usually made of stainless steel sheet by rolling, and the thickness of the stainless steel sheet is usually only about 0.5mm. The shape of the heat shield of the heat dissipation pipe of the automobile exhaust system is relatively complex, which is two symmetrical curved semicircular shells (see attached Figure 1 , 2 ). Two curved semicircular shells are buckled into a curved cylinder. Heat insulation material is arranged inside the cylinder, and after being wrapped on the heat dissipation pipe, a heat insulation layer is formed, which can prevent the heat from damaging the parts around the heat dissipation pipe and prevent the heat insulation material from scattering. Since the shape of the heat insulation cover is relatively complex, it needs to be formed by multiple calendering or stamping during calendering. In addition, the sheet material is relatively thin, which causes local stress concentration after forming, resulting in distortion or warping. For thin-walled cylindrical parts, once distortion or warping occurs, it cannot be restored to a qualified state by means of re-pressing correction, and can only be scrapped.

[0003] Obviously, the existing calendering method for the heat shield of the heat dissipation pipe of the automobile exhaust system has the problems of requiring multiple calendering or stamping and being prone to distortion or warping. Summary of the invention

[0004] In order to solve the problems of the prior art automobile exhaust system heat pipe heat shield calendering method, such as the need for multiple calendering or stamping and the easy occurrence of twisting or warping deformation, the utility model provides an automobile exhaust system heat pipe heat shield calendering die.

[0005] The utility model provides a calendering die for a heat shield of a heat dissipation pipe of an automobile exhaust system, comprising a calendering lower die and a calendering upper die; the utility model is characterized in that drawing ribs having the same direction as the edge of the forming portion are respectively arranged on both sides of a forming portion of the calendering die, that is, a slender lower die groove having the same direction as the edge of the main forming portion is respectively arranged on both sides of the forming portion of the calendering lower die, and a slender upper die protrusion is respectively arranged on both sides of the forming portion of the calendering upper die, and the position, length and direction of the upper die protrusion match those of the lower die groove; and the closing point of the upper die protrusion and the lower die groove is higher than that of other parts; in addition, the width of the calendered blank used is wider than the width between the drawing ribs on both sides of the forming portion, and the length is longer than the total length of the contour of the forming portion; wherein the closing point being higher than that of other parts means that when the calendering die is closed, the upper die protrusion and the lower die groove contact each other earlier than other parts to form compression on the calendered blank.

[0006] Furthermore, the two end heads of the calendering lower die forming part and the calendering upper die forming part are respectively provided with closed sections, that is, the two ends of the calendering lower die forming part are respectively extended outward by a set length to form a lower die closed section, and the two ends of the calendering upper die forming part are respectively extended by a set length to form an upper die closed section; so that after the calendering dies are closed, the corresponding part of the blank is pressed into a downward sealed edge; the set length of the outward extension is 5-15mm.

[0007] Furthermore, the distance between the draw rib and the edge of the forming portion is set at an equal distance, that is, the distance between any point on the draw rib and the corresponding point on the edge of the forming portion is equal.

[0008] Furthermore, a plurality of nitrogen springs are arranged at the bottom of the calendering lower die, thereby forming a floating lower die.

[0009] The beneficial technical effect of the calendering die for the heat shield of the heat pipe of the automobile exhaust system of the utility model is that before the forming part of the calendering blank begins to deform, both sides are fixed, so that the deformation is more uniform, and the distortion or warping deformation that may be caused by local stress concentration is avoided. At the same time, the deformation amount of each pass can be increased, and the number of calendering or stamping times can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Attached Figure 1 It is a three-dimensional schematic diagram of the heat shield of the radiator pipe of the automobile exhaust system;

[0011] Attached Figure 2 This is a three-dimensional schematic diagram of the heat shield of the automobile exhaust system cooling pipe from another angle.

[0012] Attached Figure 3 It is a three-dimensional schematic diagram of the calendering lower die of the heat shield of the radiator pipe of the automobile exhaust system of the utility model;

[0013] Attached Figure 4 It is a three-dimensional schematic diagram of another angle of the calendering lower die of the heat shield of the automobile exhaust system heat dissipation pipe of the utility model;

[0014] Attached Figure 5 It is a three-dimensional schematic diagram of the upper die of the calendering die of the heat shield of the radiator pipe of the automobile exhaust system of the utility model;

[0015] In the figure, 1 is a calendering lower die, 1-1 is a lower die forming part, 1-2 is a lower die groove, and 1-3 is a lower die closed section; 2 is a calendering lower die, 2-1 is an upper die forming part, 2-2 is an upper die protrusion, and 2-3 is an upper die closed section; 3 is a nitrogen spring.

[0016] The calendering die for the heat shield of the heat dissipation pipe of the automobile exhaust system of the utility model is further described below in conjunction with the accompanying drawings and specific embodiments. DETAILED DESCRIPTION

[0017] Depend on Figure 3 ,4 5. It can be seen that the calendering die for the heat shield of the heat dissipation pipe of the automobile exhaust system of the utility model comprises a calendering lower die 1 and a calendering upper die 2; it is characterized in that drawing ribs with the same direction as the edge of the forming part are respectively arranged on both sides of the forming part of the calendering die, that is, a slender lower die groove 1-2 with the same direction as the edge of the main forming part is respectively arranged on both sides of the calendering lower die forming part 1-1, and a slender upper die protrusion 2-2 is respectively arranged on both sides of the calendering upper die forming part 2-1, and the position, length and direction of the upper die protrusion match the lower die groove; and the closing point of the upper die protrusion and the lower die groove is higher than other parts; in addition, the width of the calendered blank used is wider than the width between the drawing ribs on both sides of the forming part, and the length is longer than the total length of the contour of the forming part; wherein, the closing point higher than other parts means that when the calendering die is closed, the upper die protrusion and the lower die groove contact each other earlier than other parts to press the calendered blank. When the calendering die of the heat shield of the heat pipe of the automobile exhaust system of the utility model is calendering and closing the die, the drawing ribs on both sides of the main forming part first press the two sides of the calendering blank, so that the two sides of the calendering blank are fixed before the main forming part begins to deform. Since the direction of the drawing ribs is the same as that of the main forming part, when the main forming part is deformed, the deformation and force of each part along the direction of the main forming part are similar, thereby avoiding local stress concentration of the calendering blank; at the same time, wrinkles or folds of the calendering blank are also avoided. In this way, not only can the torsion deformation or warping deformation of the calendered product be avoided, but also the deformation amount of each pass can be increased, and the number of calendering or punching times can be reduced.

[0018] As one of the preferred solutions, the two ends of the calendering lower die forming part and the calendering upper die forming part are respectively provided with closed sections, that is, the two ends of the calendering lower die forming part are respectively extended outward by a set length to form the lower die closed section 1-3, and the two ends of the calendering upper die forming part are respectively extended by a set length to form the upper die closed section 2-3; so that after the calendering die is closed, the corresponding part of the blank is pressed into a downward sealing edge; the set length of the outward extension is 5-15mm. The purpose of setting the closed section is to restrict the two ends of the calendering blank during the calendering forming process, ensure that the deformation and force of the two ends of the calendering blank are similar, and avoid local stress concentration of the calendering blank.

[0019] As one of the preferred solutions, the distance between the draw rib and the edge of the forming part is set to be equal, that is, the distance between any point on the draw rib and the corresponding point on the edge of the forming part is equal. The purpose of setting the distance between the draw rib and the edge of the forming part to be equal is to further ensure that when the forming part is deformed, the deformation and force of each part along the forming part are similar, thereby effectively avoiding local stress concentration.

[0020] In order to further improve the calendering quality and ensure that the calendered blank does not produce wrinkles or folds, as one of the preferred solutions, a plurality of nitrogen springs 3 are arranged at the bottom of the calendering lower die, thereby forming a floating lower die. One of the main characteristics of the nitrogen spring is that as the compression amount increases, the elastic resistance also increases. The closing point of the drawing rib of the calendering die of the heat shield of the automobile exhaust system heat pipe of the utility model is higher than other parts. When closing the die, the grooves and protrusions of the drawing ribs first contact each other; at this time, the nitrogen spring is in an uncompressed or slightly compressed state, and the calendered blank is not completely compressed, and can also move slightly between the upper and lower dies; when the main forming part begins to deform in large quantities, the nitrogen spring will also be in a relatively large amount of compression state, and the calendered blank has been completely compressed and can no longer move between the upper and lower dies, thereby ensuring that the deformation and force of each part of the calendered blank are similar.

[0021] Obviously, the beneficial technical effect of the calendering die for the heat shield of the heat pipe of the automobile exhaust system of the utility model is that before the forming part of the calendering blank begins to deform, both sides are fixed, so that the deformation is more uniform, and the distortion or warping deformation that may be caused by local stress concentration is avoided. At the same time, the deformation amount of each pass can be increased, and the number of calendering or stamping times can be reduced.

Claims

1. A calendering die for a heat shield of a heat pipe of an automobile exhaust system, characterized in that: The calendering die comprises a calendering lower die and a calendering upper die; it is characterized in that drawing ribs with the same direction as the edge of the forming part are respectively arranged on both sides of the calendering die forming part, that is, a slender lower die groove with the same direction as the edge of the main forming part is respectively arranged on both sides of the calendering lower die forming part, and a slender upper die protrusion is respectively arranged on both sides of the calendering upper die forming part, and the position, length and direction of the upper die protrusion match the lower die groove; and the closing point of the upper die protrusion and the lower die groove is higher than other parts; in addition, the width of the calendered blank used is wider than the width between the drawing ribs on both sides of the forming part, and the length is longer than the total length of the contour of the forming part; wherein, the closing point higher than other parts means that when the calendering die is closed, the upper die protrusion and the lower die groove contact each other earlier than other parts to press the calendered blank.

2. The calendering die for the heat shield of the heat dissipation pipe of the automobile exhaust system according to claim 1, characterized in that: The two ends of the calendering lower die forming part and the calendering upper die forming part are respectively provided with closed sections, that is, the two ends of the calendering lower die forming part are respectively extended outward by a set length to form a lower die closed section, and the two ends of the calendering upper die forming part are respectively extended by a set length to form an upper die closed section; so that after the calendering dies are closed, the corresponding part of the blank is pressed into a downward sealed edge; the set length of the outward extension is 5-15mm.

3. The calendering die for the heat insulation cover of the automobile exhaust system heat pipe according to claim 1, characterized in that: The distance between the draw rib and the edge of the forming portion is set at an equal distance, that is, the distance between any point on the draw rib and the corresponding point on the edge of the forming portion is equal.

4. The calendering die for the heat shield of the heat dissipation pipe of the automobile exhaust system according to any one of claims 1 to 3, characterized in that: A plurality of nitrogen springs are arranged at the bottom of the calendering lower die, thereby forming a floating lower die.

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