GB/T 34640.3-2017Classification and recycling and utilization of wrought aluminium and aluminium alloy scraps—Part 3: Utilization of scraps (English PDF)

1 Scope

This Part of GB/T 34640 specifies the inspection and pretreatment, complexification, casting, and environmental monitoring and discharge of wrought aluminium and aluminium alloy scraps.

This Part applies to the utilization of wrought aluminium and aluminium alloy scraps (hereinafter known as scraps for short).

2 Normative references

The following documents are indispensable for the application of this document.

For the dated references, only the editions with the dates indicated are applicable to this document. For the undated references, the latest edition (including all the amendments) are applicable to this document.

GB/T 13586 Aluminum and aluminum alloys scraps

GB/T 32186 Test methods of cleanliness of aluminium and aluminium alloy ingots

GB/T 34640.1 Classification and recycling and utilization of wrought aluminium and aluminium alloy scraps - Part 1: Classification of scraps

GB/T 34640.2 Classification and recycling and utilization of wrought aluminium and aluminium alloy scraps - Part 2: Recycling of scraps

3 Inspection and pretreatment

5 Complexification

5.1 The equipment and complexification technology used in the complexification of scraps shall be carried out in a low-oxygen environment as much as possible. During the smelting process, the aluminium liquid shall be fully stirred, to accelerate the melting of the metal, reduce the burning loss, and make the temperature and chemical composition of aluminium liquid more uniform.

5.2 After the aluminium scrap is complexified, chemical composition analysis shall be carried out; and a report form shall be issued. If used directly, USE aluminium water bag to transport to the production site; and introduce into the smelting furnace. If casted into a complexified ingot, the smelting number, designation, or group shall be identified; and it shall be stored at the designated location. The weight of a single-block complexified ingot shall be 6 kg~20 kg.

5.3 The complexification equipment shall choose double-chamber furnace, environmentally friendly, and small burning loss smelting equipment. The requirements and process control of double-chamber furnace equipment are shown in Appendix A.

6 Casting

6.1 In the case of ingredients, according to the product technical requirements of the processing enterprise and the user's use situations, the process technical document shall be developed by itself, to clarify the use quantity of various scraps.

6.2 It shall use a charging hopper and a charging vehicle for charging the furnace. Heavier scraps shall be added with clamps. Charging shall be completed at a time as much as possible, to reduce energy loss during the smelting process.

6.3 After the furnace charge is melted, it shall be fully stirred. TAKE samples for on-the-spot quick analysis. According to the detection results, the chemical composition is adjusted. After meeting the standard requirements, furnace refining shall be carried out. LET stand for a period of time before casting begins.

6.4 For aluminium and aluminium alloy ingot products with different quality requirements, according to the use of the scraps, when casting, the corresponding online purification equipment shall be provided. If necessary, detecting instruments such as online hydrogen measuring, slag measuring can be used, to ensure the internal metal cleanliness of ingot. The cleanliness shall be carried out in accordance with the requirements of GB/T 32186.

Appendix A (Informative) Double-chamber furnace equipment and process control requirements