What are the key technologies to be solved in the development and production of aluminum alloy cables?
Aluminum alloy rod conductor rod with excellent continuous casting and rolling process is the decisive factor of electrical and mechanical properties of aluminum alloy cables. Stable production of aluminum alloy rods that meet the requirements mainly starts from the following links. 1)
Calculate and determine the usage amount of aluminum ingot, intermediate alloy and Additive. After melting into the holding furnace in turn, add additive to refine and stir. At the same time, sample and analyze different points in the furnace and make corresponding adjustments when necessary. 2)
Due to the high temperature after alloy refining, it is difficult for liquid aluminum to crystallize. Pay attention to adjusting the cooling water pressure at any time to keep the crystallization wheel bright and clean so that the liquid aluminum can be crystallized smoothly. 3)
The tensile strength and elongation of the aluminum rod are strictly controlled during rolling, which is convenient for subsequent drawing and tightening of the stranded wire process.
Because the aluminum rod has internal stress, it must be stored for more than 48 hours before it can be used.
Conductor compaction process, aluminum alloy cable conductor adopts 8000 series aluminum alloy, and adopts special compaction process. In order to control the outer diameter of the cable, the compaction coefficient is generally controlled at 0.
More than 92, through the tightening of the maximum limit, make up for the shortage of aluminum alloy in volume conductivity, so that the stranded conductor wire core is like a solid conductor, obviously reducing the outer diameter of the wire core and improving the conductivity, considering the hardness of aluminum alloy material, in the process of compaction and annealing, it is necessary to select the appropriate mold, twisting speed and annealing temperature to ensure the uniform shape of aluminum alloy conductor and excellent Compaction effect.
In order to achieve better Compaction effect, different equipment can be selected according to the cross section of the wire core for twisting compaction, and the small cross section wire core adopts tubular stranding machine; Medium section wire core adopts roll forming stranding machine; The large cross-section wire core adopts frame stranding machine.
Conductor annealing process conductor annealing should follow three principles: annealing temperature, annealing time and plate loading amount.
Annealing temperature: The annealing temperature is higher than the full recrystallization temperature, but lower than the temperature of excessive grain growth.
Annealing Time: under the condition of ensuring that both internal and external conductor monofilaments are fully recrystallization, try to take the lower limit of time to improve production efficiency and reduce power consumption.
Loading quantity: the size of the conductor loading quantity has a direct impact on the performance of the conductor after annealing. Try to choose the annealing treatment with the same loading quantity, try to avoid daytime annealing, and the furnace loading quantity is best filled at one time.
Aluminum alloy belt interlocking armored process interlocking armored is a single-layer armored structure, which is characterized by the aluminum alloy belt pre-pressed into an 'S' curved surface, with the cable core as the center to rotate outside the cable core, each section of 'S' type curved surface is fastened with each other to form a layer of self-locking armored protective layer.
Armor belt adopts 5000 series aluminum alloy belt, which has good forming and processing performance, high strength, especially high fatigue strength, good corrosion resistance and weldability, but poor cutting performance.
In addition to equipment factors in the process of armor, the material performance, section geometry, size and buckle clearance of alloy belt are the technical keys. The pitch of armor is required to be consistent, uniform and flat, without cracking or disconnection, can withstand the detection related to armor.
Mold design and processing, mold station and tension adjustment, as well as the operator's experience accumulation is very important.