The process of heating and extrusion of aluminum bars & rods

Apr 18, 2023

The aluminum bar should be pre heated before entering the extruder. Traditionally, aluminum rods must be heated to a solid solution temperature in a furnace, but experience shows that this is not necessarily true. As long as the aluminum bar is properly inlaid and homogenized, it is not necessary to achieve the solid solution temperature in the aluminum rod preheating furnace. In the modern aluminum extrusion plant, the only purpose of the furnace is to soften the metal. If the metal is not heated enough to sell aluminum rolls, the formula for the calculation of aluminum rolls will not be able to pass the mold smoothly. If the aluminum bar is overheated and effectively released, the typical problems of temperature measurement in the preheating zone of aluminum rods are:

A two point type of the rmocouple will be on the low side
The daily maintenance of a two point thermocouple is often ignored
The temperature of homogenizing heat treatment is the key parameter of aluminum rod
The operator tends to overheat the aluminum rod
The operator tends to reduce the extrusion speed to fine tune the temperature changes of the aluminum bar during extrusion.

Excessive heating and slow extrusion waste the energy of preheating.
The aluminum bar should be heated to the lowest temperature that can be extruded. The aluminum roll sales specification must also ensure that the outlet temperature of the extruder reaches the target value. By reducing the preheating temperature of the aluminum bar, the extrusion speed can be raised, and the energy consumption of the reheating furnace will be reduced. Practice has proved that economic data can save energy consumption of 15-20% in gas fired furnace.
For the cheap imported products of gas heater, the temperature of the aluminum rod is measured by two point thermocouple. Because such instruments have high requirements for maintenance, V. using the superiority of such an instrument itself, or the high cost of maintenance of aluminium rolls, the aluminum volume sales test report will either lose accuracy. Some aluminum extrusion plants have started using non-contact sensors to detect and control the temperature of the heating section of the aluminum rod region. It not only reduces the dependence on the contact thermocouple thermometer, but also reduces the maintenance and accuracy problems caused by the limitations of the instrument itself.