CN112427591A

CN112427591A - Cold-heading device for metal processing

Info

Publication number: CN112427591A
Application number: CN202011105736.7A
Authority: CN
Inventors: 黄标彩; 陈伯瑜; 魏勇; 蔡常青; 王明娣; 严海峰; 陈正权
Original assignee: Fujian Sangang Minguang Co Ltd; Fujian Sangang Group Co Ltd
Current assignee: Fujian Sangang Minguang Co Ltd; Fujian Sangang Group Co Ltd
Priority date: 2020-10-15
Filing date: 2020-10-15
Publication date: 2021-03-02

Abstract

The invention relates to a cold heading device for metal processing, which comprises a cold heading machine, a cooling mechanism and a closed shell; a cooling chamber is formed inside the machine shell; the cold header carries out cold heading processing on the metal bar in a cooling chamber, and a cooling mechanism comprises a refrigerator, a refrigeration chamber, an output pipeline, a cyclone blow nozzle, an air compressor, a moisture absorber and a return pipeline; the refrigerator is cylindrical, and the cross section of the refrigerating chamber is also circular; one or more heat exchange blades are fixedly arranged on the peripheral surface of the refrigerator; the refrigerating chamber, the output pipeline, the cyclone blowing nozzle, the cooling chamber and the backflow pipeline are sequentially communicated end to form a closed circulation loop. This cold-heading device passes through gas as heat transfer medium, and its velocity of flow is fast and little to the impact nature of mould, can with the inside of mould, all outside surface direct contact and in time, quick heat transfer, reduce each local difference in temperature of mould, can greatly limit eliminate the inside stress because of the difference in temperature formation of product, ensure product property ability and quality.

Description

Cold-heading device for metal processing

Technical Field

The invention relates to the field of cold heading equipment, in particular to a cold heading device with low humidity and temperature reduction for metal processing.

Background

The cold heading is a forging method for upsetting and forming a metal bar at normal temperature by utilizing a die, and is usually used for manufacturing heads of screws, bolts, rivets and the like. In actual production, because the metal material can deform and work harden during cold heading, a large amount of heat can be generated in the process of rapid plastic deformation, and therefore the temperature of the die needs to be reduced in time; the cooling effect of the existing die is general, so that the temperature of the die is extremely high, the service life of the cold heading die is influenced to a great extent, and the manufacturing precision of the product is reduced.

In addition, the existing cooling devices mostly adopt a spraying or mist spraying mode using water as a heat absorbing medium, the humidity of the cooling environment is in a high value state for a long time, and the conditions of high temperature, sufficient oxygen and the like of the surface of the mold are combined, so that the surface of the mold is easy to rust and corrode, and further the processing quality of workpieces is influenced. In addition, the cooling method of the spray or mist method is not ideal in terms of cooling effect because the replacement speed of the heat absorbing medium is generally slow, and the heat absorbing medium is generally difficult to cover all surfaces of the mold, so that the mold is likely to have uneven cooling and heating at various portions, which is likely to affect the service life and product quality of the mold.

Disclosure of Invention

The invention provides a cold heading device for metal processing, which aims to solve the problems that most existing cold heading devices are poor in cooling effect, the surfaces of dies are easy to rust and corrode, the service life is short, and the product quality of workpieces is affected.

The invention adopts the following technical scheme:

a cold heading device for metal processing comprises a cold heading machine, a cooling mechanism and a closed shell; the interior of the cabinet forms a cooling chamber. The cold header carries out cold heading processing on the metal bar in the cooling chamber, and the cooling mechanism comprises a refrigerator, a refrigeration chamber, an output pipeline, a cyclone blow nozzle, an air compressor, a moisture absorber and a return pipeline; the refrigerator is cylindrical, the cross section of the refrigerating chamber is also circular, the refrigerator is coaxially and fixedly arranged in the refrigerating chamber, and the refrigerator is used for cooling gas flowing through the refrigerating chamber; the cooling gas is nitrogen, inert gas or air. One or more heat exchange blades are fixedly arranged on the peripheral surface of the refrigerator; the refrigerating chamber, the output pipeline, the cyclone blowing nozzle, the cooling chamber and the backflow pipeline are sequentially communicated end to form a closed circulation loop, and the inner walls of the output pipeline and the backflow pipeline are respectively and fixedly provided with the moisture absorber for dehumidifying flowing cooling gas; the air compressor machine is communicated with the output pipeline and is used for driving the cooling gas to continuously and unidirectionally circulate at high speed in the circulation loop.

Furthermore, the swirl blowing nozzle comprises a swirl section and a trumpet-shaped diffusion section which are sequentially communicated, at least one first air inlet connecting pipe is fixedly arranged on the outer peripheral surface of the swirl section, the first air inlet connecting pipe extends along the tangential direction of the inner peripheral wall of the swirl section, and the output pipeline conveys cooling gas to the swirl section through the first air inlet connecting pipe. Preferably, the cyclone section is provided with two, three, four or six first air inlet connecting pipes which are rotationally symmetrically distributed. The male die and the female die of the cold forging machine are respectively provided with at least one swirl blowing nozzle, the swirl blowing nozzles are fixedly assembled on the inner wall of the shell, and the swirl blowing nozzles blow cooling gas towards the corresponding male die and the female die in a die closing state.

In a further improvement mode, the heat exchange blades are in a spiral structure or are distributed in a spiral structure, and the distance between the outer edge of each heat exchange blade and the inner peripheral wall of the refrigeration chamber is 0.22-0.25 times of the inner diameter of the refrigeration chamber; the heat exchange blades are randomly distributed with a plurality of vent holes.

In a further improvement, a second air inlet connecting pipe is arranged on the end surface of the rotational flow section; the extending direction of the second air inlet connecting pipe and the axial direction of the rotational flow section form an included angle of 0-30 degrees, or the extending direction of the second air inlet connecting pipe and the axial direction of the rotational flow section are parallel and are not coaxially arranged.

In a further improvement, the cross-sectional area of the second intake connecting pipe is greater than or equal to the cross-sectional area of all the first intake connecting pipes.

In a further improvement, the swirl blowing nozzle is arranged at the high position of the cooling chamber, and the swirl section of the return pipeline is arranged at the low position of the cooling chamber.

Further improve ground, set respectively in above-mentioned output pipeline and the above-mentioned return duct above-mentioned air compressor machine, the air compressor machine of output pipeline assembly is bloied towards above-mentioned cooling chamber direction, and the air compressor machine of return duct assembly is bloied towards above-mentioned refrigeration chamber direction.

In a further improvement, the outer peripheral surfaces of the output pipeline and the swirl blowing nozzle are respectively coated with an insulating layer.

From the above description of the structure of the present invention, compared with the prior art, the present invention has the following advantages: the cold heading device of the invention takes gas as a heat exchange medium, has fast flow speed and small impact on the die, can directly contact with all the outer surfaces of the inside and the outside of all the dies to exchange heat in time and fast, reduces the temperature difference of each local part of the die, and ensures the product performance and the quality. In addition, this output pipeline jets into the whirl section with cooling gas along the tangent line and forms rotatory air current for cooling gas advances forward along the spiral path in the whirl blowing nozzle and through the diffusion of diffuser, is favorable to cooling gas can be fast and in all spaces in the cooling chamber of comprehensive diffusion, makes cooling gas can carry out comprehensive and quick high-efficient cooling to the mould in the cooling chamber. In addition, the cooling gas continuously and circularly flows in a unidirectional way in the closed circulating loop, so that the dryness of the cooling gas is ensured, the heat exchange stability of the cooling gas is facilitated, and the chemical attack on the die is reduced to ensure the product quality of the workpiece. Finally, the space structure and the shape of the refrigerator and the refrigeration chamber effectively improve the contact rate of the cooling gas and the heat exchange blades, effectively improve the cooling effect of the cooling gas, lower the temperature when the cooling gas is output, and the arrangement of the vent holes is favorable for improving the trafficability of the cooling gas and the contact area of the cooling gas and the heat exchange blades, and is favorable for improving the heat exchange efficiency.

Drawings

Fig. 1 is a schematic front view of the cold heading device according to the embodiment.

Fig. 2 is a schematic sectional structure view of the swirling flow section of the present embodiment.

Fig. 3 is a right structural schematic view of the refrigerator with a single heat exchange blade according to the embodiment.

Fig. 4 is a schematic right-view structural view of a refrigerator having a plurality of heat exchange blades according to the present embodiment.

Detailed Description

The following describes embodiments of the present invention with reference to the drawings.

Referring to fig. 1, the cold heading apparatus for metal working of the present embodiment includes a cold heading machine 1, a cooling mechanism 2, and a housing 3 in a closed state; the metal workpiece is subjected to cold heading processing in the cold heading machine 1, a cooling chamber 30 is formed inside the housing 3, and the cold heading machine 1 is used for carrying out cold heading processing on the metal bar material in the cooling chamber 30.

With continued reference to fig. 1, the cooling mechanism 2 includes a refrigerator 21, a refrigerating chamber 22, an output duct 23, a swirl nozzle 24, a moisture absorber 28, an air compressor 25, and a return duct 26. With continued reference to fig. 1, 3 and 4, the refrigerator 21 is fixedly installed in the refrigerating chamber 22, the refrigerator 21 is used for cooling the cooling gas flowing through the refrigerating chamber 22, the refrigerator 21 is cylindrical, the cross section of the refrigerating chamber 22 is circular, and the refrigerator 21 is coaxially and fixedly installed in the refrigerating chamber 22; one or more heat exchange blades 27 are fixedly provided on the outer peripheral surface of the refrigerator 21. Further, the heat exchange blades 27 are in a spiral structure or are distributed in a spiral structure, and the distance between the outer edge of the heat exchange blade 27 and the inner peripheral wall of the refrigeration chamber 22 is 0.22-0.25 times of the inner diameter of the refrigeration chamber 22; referring to fig. 3, the heat exchange fins 27 are provided with a plurality of ventilation holes in a random distribution. The space structure and shape of the refrigerator 21 and the refrigerating chamber 22 effectively improve the contact rate of the cooling gas and the heat exchange blades 27, effectively improve the cooling effect of the cooling gas, lower the temperature when the cooling gas is output, and the vent holes are arranged to improve the trafficability of the cooling gas and the contact area of the cooling gas and the heat exchange blades 27, thereby being beneficial to improving the heat exchange efficiency.

With continued reference to FIG. 1, the swirl-blowing nozzle 24 is disposed at a high position in the cooling chamber 30, and the swirl section of the return conduit 26 is disposed at a low position in the cooling chamber 30. And it is preferable that the outer circumferential surfaces of the output duct 23 and the cyclone blowing nozzle 24 are coated with heat insulating layers, respectively. Preferably, the air compressor 25 is disposed in each of the outlet duct 23 and the return duct 26, the air compressor 25 attached to the outlet duct 23 blows air in a direction toward the cooling compartment 30, and the air compressor 25 attached to the return duct 26 blows air in a direction toward the cooling compartment 22. Refrigeration room 22, output pipeline 23, whirl blow gun 24, cooling chamber 30, return line 26 communicate end to end in proper order and form closed circulation circuit, and air compressor machine 25 communicates with this output pipeline 23, and air compressor machine 25 is used for driving this cooling gas and lasts unidirectional high-speed circulation flow in this circulation circuit. One or two swirl nozzles 24 are respectively arranged on the male die 11 and the female die 12 of the cold forging die of the cold forging machine 1, the swirl nozzles 24 are fixedly assembled on the inner wall of the shell 3, and the swirl nozzles 24 blow cooling gas towards the corresponding male die 11 and the female die 12 in a matched die state.

With continued reference to fig. 1, the inner walls of the output duct 23 and the return duct 26 are respectively fixedly equipped with two moisture absorbers 28 for dehumidifying the cooling gas flowing through, and the moisture absorbers 28 are preferably mounted on the inner walls of the ducts in a non-isolated manner, that is, the outer surface of the moisture absorber 28 and the corresponding inner wall of the duct form a channel with a smaller cross-sectional area than other positions, and the cooling gas passes through the channel in a crossing manner, so as to gradually dehumidify most of the cooling gas through continuous circulation.

With continued reference to fig. 1, the heat exchange in the cooling mechanism 2 works as follows: as shown by the flowing direction of the cooling gas indicated by the solid arrows in fig. 1, the refrigerator 21 operates to absorb the ambient heat and lower the ambient temperature, the heat exchange blades 27 on the periphery of the refrigerator 21 are also cooled synchronously, the cooling gas blown into the refrigerating chamber 22 by the return pipe 26 transfers the heat to the cooling gas flowing through the refrigerator 21 and the heat exchange blades 27, so that the temperature of the cooling gas is rapidly lowered and is delivered into the cooling chamber 30 by the output pipe 23 and the cyclone blowing nozzle 24, the low-temperature cooling gas passes through the outer surfaces of the inner and outer parts of each mold and rapidly takes away the heat on the surface passing through the low-temperature cooling gas, so that the surface of each mold is cooled, and the cooling gas carrying the heat is input into the refrigerating chamber 22 by the return pipe 26 to complete a primary circulation. The cooling gas continuously and circularly flows in a unidirectional way in the closed circulating loop, so that the dryness of the cooling gas is ensured, the heat exchange stability of the cooling gas is facilitated, and the chemical attack on the die is reduced to ensure the product quality of the workpiece.

With continued reference to fig. 1, the swirl blowing nozzle 24 includes a swirl section 241 and a flared diffuser section 242 which are sequentially communicated, at least one first air inlet connecting pipe 243 is fixedly arranged on the outer peripheral surface of the swirl section 241, the first air inlet connecting pipe 243 extends along the tangential direction of the inner peripheral wall of the swirl section, and the output pipeline 23 conveys cooling gas to the swirl section 241 through the first air inlet connecting pipe 243; preferably, the cyclone segment 241 is provided with two, three, four or six first air inlet connecting pipes 243 which are rotationally symmetrical. The cooling gas may be air, but is preferably nitrogen, an inert gas.

With reference to fig. 1 and 2, the cold heading device of the present embodiment uses gas as a heat exchange medium, and has a fast flow rate and a small impact on the die, so that the cold heading device can directly contact with all the external surfaces inside and outside the die to exchange heat in time and quickly, thereby reducing the temperature difference of each local part of the die, eliminating the stress formed by the temperature difference inside the product to the maximum extent, and ensuring the product performance and quality. In addition, the output pipeline 23 injects the cooling gas into the cyclone section along a tangent line to form a rotating airflow, so that the cooling gas is propelled forwards along a spiral path in the cyclone blowing nozzle 24 and is diffused by the diffusion section 242, which is beneficial to rapidly and comprehensively diffusing all spaces in the cooling chamber 30, and the cooling gas can comprehensively and rapidly and efficiently cool the mold in the cooling chamber 30.

A second air inlet connecting pipe 244 is arranged on the end surface of the rotational flow section 241; the extending direction of the second air inlet connecting pipe 244 forms an included angle of 0-30 degrees with the axial direction of the rotational flow section 241, or the extending direction of the second air inlet connecting pipe 244 is parallel to the axial direction of the rotational flow section 241 and is not coaxially arranged. And the cross-sectional area of the second air inlet connection pipe 244 is greater than or equal to the cross-sectional area of all the first air inlet connection pipes 243. The second air inlet connection pipe 244 is configured such that the cooling gas blown into the second air inlet connection pipe is the main stream gas, and the first air inlet connection pipe 243 is the auxiliary stream gas, and the auxiliary stream gas and the main stream gas can collide with each other and be guided to form a rotationally advancing air stream after meeting each other, so that the flowing speed of the air stream can be increased, the flowing smoothness of the air stream can be improved, the cooling gas newly blown into the cooling chamber 30 can be promoted to quickly and comprehensively replace the old air in the cooling chamber 30, the air stream circulation efficiency in the circulation loop can be effectively promoted, and the heat exchange efficiency between each mold and the cooling gas can be ensured.

The above description is only an embodiment of the present invention, but the design concept of the present invention is not limited thereto, and any insubstantial modifications made by using the design concept should fall within the scope of infringing the present invention.

Claims

1. A cold heading device for metal processing comprises a cold heading machine, a cooling mechanism and a closed shell; a cooling chamber is formed inside the machine shell; the method is characterized in that:

the cold header performs cold heading processing on the metal bar in the cooling chamber, and the cooling mechanism comprises a refrigerator, a refrigeration chamber, an output pipeline, a cyclone blow nozzle, an air compressor and a return pipeline; the refrigerator is cylindrical, the cross section of the refrigerating chamber is also circular, the refrigerator is coaxially and fixedly arranged in the refrigerating chamber, and the refrigerator is used for cooling gas flowing through the refrigerating chamber; one or more heat exchange blades are fixedly arranged on the peripheral surface of the refrigerator; the refrigerating chamber, the output pipeline, the cyclone blowing nozzle, the cooling chamber and the backflow pipeline are sequentially communicated end to form a closed circulation loop; the air compressor is communicated with the output pipeline and is used for driving the cooling gas to continuously and unidirectionally circulate and flow in the circulation loop at a high speed;

the cyclone blowing nozzle comprises a cyclone section and a flared diffusion section which are sequentially communicated, at least one first air inlet connecting pipe is fixedly arranged on the outer peripheral surface of the cyclone section, the first air inlet connecting pipe extends along the tangential direction of the inner peripheral wall of the cyclone section, and the output pipeline conveys cooling gas to the cyclone section through the first air inlet connecting pipe;

the male die and the female die of the cold forging machine are respectively provided with at least one swirl blowing nozzle, the swirl blowing nozzles are fixedly assembled on the inner wall of the shell, and the swirl blowing nozzles blow cooling gas towards the corresponding male die and the female die in a die closing state.

2. The cold heading apparatus for metal working according to claim 1, wherein: the heat exchange blades are in a spiral structure or are distributed in a spiral structure, and the distance between the outer edge of each heat exchange blade and the inner peripheral wall of the refrigeration chamber is 0.22-0.25 time of the inner diameter of the refrigeration chamber; the heat exchange blades are randomly distributed with a plurality of vent holes.

3. The cold heading apparatus for metal working as claimed in claim 2, wherein: a second air inlet connecting pipe is arranged on the end face of the rotational flow section; the extending direction of the second air inlet connecting pipe and the axial direction of the rotational flow section form an included angle of 0-30 degrees, or the extending direction of the second air inlet connecting pipe and the axial direction of the rotational flow section are parallel and are not coaxially arranged.

4. A cold heading device for metal working according to claim 3, wherein: the cross-sectional area of the second air inlet connecting pipe is larger than or equal to that of all the first air inlet connecting pipes.

5. The cold heading apparatus for metal working according to claim 1, wherein: and the inner walls of the output pipeline and the return pipeline are respectively fixedly provided with a moisture absorber for dehumidifying cooling gas flowing through.

6. The cold heading apparatus for metal working according to claim 1, wherein: the swirl blowing nozzle is arranged at the high position of the cooling chamber, and the swirl section of the backflow pipeline is arranged at the low position of the cooling chamber.

7. The cold heading apparatus for metal working according to claim 1, wherein: the outer peripheral surfaces of the output pipeline and the cyclone blowing nozzle are respectively coated with heat insulation layers.

8. The cold heading apparatus for metal working according to claim 1, wherein: the cooling gas is nitrogen, inert gas or air.