Most of the aluminum tubes on the market are produced using conventional combined die welding and extrusion processes, which cannot completely avoid welding lines, especially after oxidation, which is prone to dark lines. In extrusion production, short round rods, high temperature, and slow speed extrusion processes are used. In particular, the "three temperatures" must be controlled. The aluminum rod, extrusion barrel, and mold must be kept clean. The aging time and temperature are determined according to the thickness of the tube wall. Just make appropriate adjustments to the pipe diameter.
The aluminum tube extrusion machine currently used includes an extrusion box and a cylinder. The heated aluminum block is put into the extrusion box from the feed port. The cylinder starts to work so that the extrusion beam pushes the aluminum block toward the extrusion die. The high temperature The aluminum block in the state has good plasticity. When the temperature of the aluminum block decreases, the plasticity will also decrease. Under the action of a certain pressure and speed of the extrusion beam, the extrusion pad pushes the aluminum block to generate plastic flow and is extruded from the extrusion die. , thereby obtaining an aluminum tube with the required cross-sectional shape and size; during the extrusion process, the aluminum block is under strong pressure in the extrusion deformation zone, which can fully exert its plasticity and obtain large deformation. At the same time, the extrusion deformation can be improved. The structure of metal materials improves their mechanical properties,
especially for aluminum blocks with extrusion effects. After quenching and aging, the longitudinal (extrusion direction) mechanical properties of extruded products are much higher than similar products produced by other processing methods. Press processing also has great flexibility. Products with different shapes, sizes, and varieties can be produced on the same equipment by simply changing the extrusion die. The operation of changing the extrusion die is simple, convenient, less time-consuming, and highly efficient. However, there are still big problems with the forming of some double-layer seamless aluminum tubes. Therefore, it is necessary to improve this situation.
Seamless aluminum pipes generally use the perforation extrusion method. Since seamless aluminum pipes have the characteristics of small specific gravity, easy processing, and high mechanical strength, in fact, the production process requirements of seamless aluminum pipes are relatively strict and precise.
