CN-122007192-A - Extrusion molding control method of automobile luggage rack profile and automobile luggage rack profile

CN122007192ACN 122007192 ACN122007192 ACN 122007192ACN-122007192-A

Abstract

The application relates to the field of aluminum alloy extrusion control, and provides an automobile luggage rack profile extrusion molding control method and an automobile luggage rack profile, which are used for obtaining a die cavity structural parameter, a profile section functional partition parameter and historical normal batch process data, determining radial preheating zone temperature reference values of different radial positions of a bar, axial heating zone temperature reference values of different axial positions and initial extrusion speed, wherein the position of the bar, which is radially close to a surface layer, corresponds to higher preheating temperature, the method is used for extruding a thick-wall area of a profile, the temperature near a core part is lower, the method is used for extruding a thin-wall area, the radial and axial actual temperatures are acquired in real time in the extrusion process, each section functional partition corresponds to the metal flow velocity of a discharge port, the difference value of the maximum and minimum flow velocities, namely the discharge flow velocity difference extreme value, is calculated, if the difference value is between a first threshold value and a second threshold value, the preheating temperature of the corresponding area is adjusted, the extrusion speed is reduced, and the effective quality control of the thick-wall area of the profile of the luggage rack can be realized.

Inventors

LEI XIAOHONG
LI WEIJIN
CAO XIAOJUN

Assignees

清远市钛美铝业有限公司

Dates

Publication Date: 20260512
Application Date: 20260323

Claims (10)

1. An extrusion control method of a luggage rack profile of an automobile, which is characterized by comprising the following steps: The method comprises the steps of obtaining a die cavity structural parameter, profile section functional partition parameters and historical normal batch process data, determining radial preheating zone temperature reference values of bar stocks at different radial positions, axial heating zone temperature reference values of bar stocks at different axial positions and initial extrusion speeds according to the die cavity structural parameter, the profile section functional partition parameters and the historical normal batch process data, starting a preheating system and an extrusion feeding mechanism according to the radial preheating zone temperature reference values at different radial positions, the axial heating zone temperature reference values at different axial positions and the initial extrusion speeds before bar stocks are fed, wherein the profile section functional partition comprises a profile thin-wall region and a profile thick-wall region, the position of the bar stocks, which are close to a surface layer in the radial direction, corresponds to a higher preheating zone temperature reference value, the position of the bar stocks, which are close to a bar stock surface layer in the radial direction, corresponds to a lower preheating zone temperature reference value, and the position of the bar stocks, which are close to a core part in the radial direction, corresponds to a thin-wall section of the extrusion molding profile; In the extrusion process, acquiring actual temperatures of the bar stock in radial preheating areas at different radial positions and actual temperatures of the bar stock in axial heating areas at different axial positions, acquiring a plurality of discharge port metal flow rates corresponding to the section functional partitions of the plurality of profiles, and determining the maximum flow rate and the minimum flow rate in the plurality of discharge port metal flow rates; When the discharge flow velocity difference extreme value is smaller than the first flow velocity difference extreme value, the temperature reference values of the radial preheating areas at different radial positions are kept unchanged, when the discharge flow velocity difference extreme value is larger than the first flow velocity difference extreme value and smaller than the second flow velocity difference extreme value, a first temperature increment and a first extrusion speed reduction amplitude are obtained, a low flow velocity cross-section area and a high flow velocity cross-section area are determined, the first temperature increment is increased for the radial preheating area corresponding to the low flow velocity cross-section area, the first temperature increment is reduced for the radial preheating area corresponding to the high flow velocity cross-section area, and the first extrusion speed reduction amplitude is reduced for the extrusion speed.
2. The method of claim 1, wherein determining a low flow cross-sectional area and a high flow cross-sectional area comprises: the method comprises the steps of obtaining a thick-wall cross section corresponding to a thick-wall cross section and a bar cross section, determining a preheating area factor of the thick-wall cross section and the bar cross section corresponding to the thick-wall cross section, and determining the product of the bar radius and the preheating area factor as a high-flow-rate cross section radius; And determining the area of the cross section of the bar except the high flow rate cross section area as the low flow rate cross section area.
3. The method according to claim 2, wherein the method further comprises: increasing a first temperature increment for a radial preheating zone corresponding to a low-flow-rate cross-section area, reducing the temperature of the radial preheating zone corresponding to a high-flow-rate cross-section area by the first temperature increment, reducing the extrusion speed by a first extrusion speed reduction amplitude, and acquiring an adjusted discharge flow speed difference extreme value; When the discharge flow velocity difference extreme value is greater than the first flow velocity difference extreme value and smaller than the second flow velocity difference extreme value, increasing a preset preheating area factor for the preheating area factor to obtain an adjusted preheating area factor, redefining a low flow velocity cross section area and a high flow velocity cross section area according to the adjusted preheating area factor, increasing a first temperature increment for a radial preheating area corresponding to the low flow velocity cross section area, reducing the temperature of the radial preheating area corresponding to the high flow velocity cross section area by the first temperature increment, and reducing the extrusion speed by a first extrusion speed reduction width.
4. A method according to claim 3, characterized in that the method further comprises: the method comprises the steps of obtaining a supplementary preheating power factor and a supplementary preheating time factor, obtaining the preheating power of a radial preheating zone corresponding to a high-flow-rate cross-section area as initial preheating power, obtaining the preheating time of the radial preheating zone corresponding to the high-flow-rate cross-section area as initial preheating time, determining the product of the supplementary preheating power factor and the initial preheating power as supplementary preheating power, and determining the product of the supplementary preheating time factor and the initial preheating time as supplementary preheating time; When the discharge flow velocity difference extreme value is adjusted to be larger than the first flow velocity difference extreme value and smaller than the second flow velocity difference extreme value, the radial preheating zone corresponding to the high flow velocity cross section area is subjected to supplementary preheating according to the supplementary preheating power and the supplementary preheating time, so that the surface layer flow of the high flow velocity cross section area is improved.
5. The method according to claim 4, wherein the method further comprises: And when the radial preheating zone corresponding to the high-flow-rate cross section area is subjected to supplementary preheating according to the supplementary preheating power and the supplementary preheating time, synchronously reducing the supplementary extrusion speed and reducing the amplitude of the extrusion speed at different stages.
6. The method of claim 5, wherein the method further comprises: the supplementary preheating power factor is 1.2-1.5, the supplementary preheating time factor is 0.1-0.2, and the supplementary extrusion speed is reduced by 0.05-0.1.
7. The method of claim 6, wherein the method further comprises: When the discharge flow velocity difference extreme value is larger than the second flow velocity difference extreme value, acquiring a second temperature increment and a second extrusion speed amplitude reduction, determining a low flow velocity cross section area and a high flow velocity cross section area, increasing the second temperature increment for a radial preheating area corresponding to the low flow velocity cross section area, reducing the second temperature increment for a radial preheating area corresponding to the high flow velocity cross section area, and synchronously reducing the second extrusion speed amplitude reduction for the extrusion speed until the discharge flow velocity difference extreme value falls back to be smaller than the first flow velocity difference extreme value, wherein the second temperature increment is larger than the first temperature increment, and the second extrusion speed amplitude reduction is larger than the first extrusion speed amplitude reduction.
8. The method of claim 7, wherein the method further comprises: determining the difference value of the metal flow rates of the plurality of discharge ports at adjacent moments as a flow rate absolute difference value; when the absolute difference of the flow velocity is larger than the absolute difference of the preset flow velocity, or the reference flow velocity difference is larger than the preset reference flow velocity difference, synchronously increasing the temperature reference value of the radial preheating zone of the bar at different radial positions by the first temperature reference value, and reducing the temperature reference value of the axial heating zone at different axial positions by the second temperature reference value.
9. The method of claim 8, wherein the method further comprises: Synchronously increasing a first temperature reference value for the temperature reference value of a radial preheating zone of the bar at different radial positions, reducing a second temperature reference value for the temperature reference value of an axial heating zone at different axial positions, reducing the extrusion speed by a first extrusion speed reduction width, acquiring a flow velocity absolute difference value as an adjustment flow velocity absolute difference value, and acquiring a reference flow velocity difference value as an adjustment reference flow velocity difference value; And when the adjustment flow velocity absolute difference is larger than the preset flow velocity absolute difference or the adjustment reference flow velocity difference is larger than the preset reference flow velocity difference, increasing the preset initial extrusion velocity for the initial extrusion velocity.
10. An automotive luggage rack profile, characterized in that it is manufactured by the extrusion control method of an automotive luggage rack profile according to any one of claims 1 to 9.

Description

Extrusion molding control method of automobile luggage rack profile and automobile luggage rack profile Technical Field The application relates to the technical field of aluminum alloy extrusion control, in particular to an extrusion molding control method of an automobile luggage rack profile and the automobile luggage rack profile. Background The profile structure of a vehicle roof rack usually has both thin-walled regions and thick-walled regions. In the prior art, the processing and the preparation of the automobile luggage rack are mainly finished by adopting extrusion molding, namely, an external force is applied to a bar through an extrusion die, so that the bar is promoted to flow through a molding cavity of the die to obtain the luggage rack profile with the corresponding cross-section shape. As a core component in the process, the cavity structure and the runner design of the extrusion die directly determine the dimensional accuracy and the appearance quality of the extruded profile, and the conventional extrusion die can generally meet the molding requirement when facing the profile processing requirement of uniform wall thickness, so that the extrusion die is widely applied to batch production links of various aluminum profiles and alloy profiles for a long time. In the existing luggage rack profile extrusion process, the whole preheating temperature of bars is always consistent and is influenced by the difference of metal flow resistance corresponding to different wall thickness areas, the blank flow rate of the thin wall area is possibly lower than that of the thick wall area, the problem that the thin wall area is easy to be filled with the material and the thickness is not up to the design requirement is possibly caused, the problem that the thick wall area is easy to be filled with the material and the thickness is not up to the design requirement is also possibly caused, and the defects of surface bulge and size out-of-tolerance caused by overfilling of the thick wall area are also possibly caused. Meanwhile, the cooling shrinkage rates of the thin-wall area and the thick-wall area are different, when the same preheating temperature is adopted in the thin-wall area and the thick-wall area, the situation of uneven internal stress distribution easily occurs after the profile is demolded, so that the profile is integrally warped and deformed, and the structural strength and the assembly precision of the automobile luggage rack are seriously affected. Therefore, the existing extrusion dies cannot achieve effective quality control for the thin-walled region and the thick-walled region of the automobile luggage rack profile. Disclosure of Invention The application aims to provide an extrusion molding control method of an automobile luggage rack profile and the automobile luggage rack profile, which solve the technical problem that the existing extrusion mold cannot control the effective quality of the profile thin-wall area and the profile thick-wall area of the automobile luggage rack, and achieve the technical effect of controlling the effective quality of the profile thin-wall area and the profile thick-wall area of the automobile luggage rack. In a first aspect, an embodiment of the present application provides a method for controlling extrusion molding of a profile of an automobile luggage rack, where the method includes obtaining a mold cavity structural parameter, a profile section functional partition parameter, and historical normal batch process data; determining a radial preheating zone temperature reference value of a bar at different radial positions, an axial heating zone temperature reference value of the bar at different axial positions and an initial extrusion speed according to a die cavity structural parameter, a plurality of profile section functional partition parameters and historical normal batch process data, starting a preheating system and an extrusion feeding mechanism according to the radial preheating zone temperature reference value of the different radial positions, the axial heating zone temperature reference value of the different axial positions and the initial extrusion speed before feeding the bar, wherein the plurality of profile section functional partition comprises a profile thin-wall area and a profile thick-wall area, the position of the bar at the radial position close to a surface layer corresponds to a higher preheating zone temperature reference value, the position of the bar at the radial position close to the bar surface layer corresponds to a lower preheating zone temperature reference value, the position of the bar at the radial position close to the core part is used for extruding a thin-wall section of the profile, acquiring the actual temperature of the bar at the radial preheating zone at the different radial positions and the axial heating zone temperature of the bar at the different axial positions during extrusion, acquiring a plurality of