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Solar frame aluminum extrusion production control

Solar frame aluminum extrusion production control
Solar energy is a new type of pollution-free green energy.The frame of the battery plate and its supporting structure, such as the pillars, tie rods and supporting legs, can be extruded with the most economical and durable aluminum alloy materials at present, and it is a new market for the application of aluminum alloy materials, and has been applied in the world.

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1. Optimize the design and manufacture of aluminium extrusion die

Aluminium extrusion die is an important tool to ensure the shape and dimension precision of solar photovoltaic aluminum profile products. The design and manufacturing quality of extrusion die is important to achieve high quality, high yield, low consumption, high efficiency and low cost. Therefore, to produce high precision photovoltaic aluminum alloy profile, it is necessary to optimize the design and manufacture of extrusion die.

1.1 Use advanced extrusion die manufacturing equipment

For extrusion die processing the advanced equipment with high precision is the prerequisite for ensuring the extrusion die to be qualification. Therefore, advanced processing equipment such as CNC, slow wire cutting, three axis machining center and EDM center should be used to improve the precision and performance of the die in the production of PV aluminum profiles.

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1.2 reasonable feeding holes

In order to ensure the good symmetry of photovoltaic aluminum profile and improve the production efficiency and the yield, the die feeding holes must follow the central symmetry principle and adopt the symmetrical arrangement of multi-cavity holes. During the design of die, the bridge position shall be designed on the non decorative surface of profile to avoid the defects exposed.

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1.3 Optimize the bearing design

The die bearing is the part of stabilizing the product size and ensuring the surface quality. When designing the bearing length, the difference should be minimized, the length change should be even, and the obstruction angle and the flow promotion angle should be adopted to reduce the aluminium flow rate, so as to achieve the goal of uniform metal flow and improving the surface quality of the profile.

2. Chemical composition control

6063 aluminum alloy has become an important choice for the production of high precision photovoltaic aluminum alloy profiles. The alloy is Mg2Si series, which has good extrusion property and low quenching sensitivity. It has good high temperature plasticity, wide quenching temperature range and small critical quenching speed. In the range of 6063 aluminum alloy composition specified in GB/T3190 standard, different values of chemical composition will obtain different material properties. When the range of chemical composition is large, the performance difference will fluctuate in a large range, so that the comprehensive properties of profiles will be difficult to control. In order to ensure the precision of photovoltaic aluminum alloy profile, it is necessary.The chemical composition of the alloy must be determined in strict accordance with the enterprise control standards.

3. Smelting, casting and ingot homogenization process

3.1 Smelting and refining process

The temperature of the smelting is 720-760 ℃ by rotary regenerative melting furnace. At temperature above 720 ℃, high purity nitrogen was used to blow into the refining agent for 15min, the refining agent dosage was 0.08% of the melt weight, electromagnetic stirring was conducted for 15min after refining, and the aluminum liquid was kept for 20-30min. The chemical composition of aluminum alloy solution is strictly controlled by sampling inspection, so that the material can meet the required mechanical properties.

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3.2 Casting process

Semi continuous direct water cooling casting method was used. The direct water cooling method has the advantages of high cooling strength and fast cooling speed, which makes the casting structure fine and increases the density of the structure, and then improves the mechanical properties and heat treatment effect of the ingot. The casting temperature is 710-730 ℃, casting speed is 50-70mm/min, and cooling water pressure is 0.1-0.3mpa. In order to reduce the tendency of thermal crack and improve the chemical composition of the alloy, aluminum titanium boron wire was added online, and the adding speed was 1700-2000mm / min.

3.3 Homogenization of cast rod structure

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In order to reduce and eliminate the segregation in the ingot and improve the inhomogeneity of its chemical composition and structure, the aluminum alloy bar was homogenized. The technical conditions of control are heating the casting rod to 540-550 ℃, holding heat for 8-10h, cooling by strong wind and water mist cooling. After homogenization annealing, cooling should be accelerated to ensure the uniformity of color after anodizing.

4. Technical control of extrusion and aging process

The extrusion, on-line quenching and aging of 6063 aluminum alloy profile were studied. The heating temperature of the casting rod was controlled: 440-480 ℃; The heating temperature of the mould: 450-480 ℃, the heating time of the mold is less than 5 hours; The heating temperature of extrusion cylinder is 460-500 ℃; Extrusion speed: 12-18m/min; The temperature of discharge port is 510-550 ℃; The cooling mode is on-line air cooling or water mist cooling; Aging treatment for extrusion profile after on-line quenching: control temperature is 200 ± 5 ℃, holding time: 3 hours. The combination of solid solution treatment and extrusion process of 6063 aluminum alloy can avoid grain growth and improve the physical and mechanical properties of the profile products.