Control of Key Processes in Aluminum Profile Extrusion Workshop

1. According to the homework plan, select the mold that meets the plan. Flat mold: 460 ℃ -480 ℃ B. Split mold: 480 ℃ -500 ℃. The retention time of the mold in the furnace should not exceed 8 hours, and the mold installation process should be rapid and fast, and the mold should be prevented from cooling.

2. The ingot container must be kept clean and free from severe wear or large belly, otherwise the extruded product will have slag inclusions or bubbles.

3. Aluminum alloy round ingots are not allowed to roll on the ground. Any surface with sediment or dust should be cleaned before being heated in the furnace.

The temperature setting of the aluminum rod heating furnace is set at 300 ℃ -450 ℃ during the heating stage. When the aluminum rod is put on the machine, the temperature should be controlled according to the wall thickness, which should be T ≥ 1.4mm. The temperature should be controlled at 440 ℃ -540 ℃, and T<1.4mm should be controlled at 400 ℃ -540 ℃. The specific situation depends on the variety, mold structure, and alloy type.

4. Before heating in the furnace, aluminum alloy round ingots should undergo surface quality self inspection, which is the responsibility of the host operator. Any round ingots with obvious slag inclusions, cold shuts, central cracks, and bends should not be heated in the furnace, and should be selected and returned to the melting and casting workshop.

5. Use a temperature gradient of 100 ℃/1 hour to heat the ingot container to 380 ℃ -420 ℃. The end face temperature of the ingot cylinder is 280 ℃ -360 ℃

6. The end face of the ingot cylinder and the mold should be flat and free from damage and aluminum adhesion, otherwise material may run off during extrusion. During the extrusion process, the extrusion team leader should use a handheld thermometer to measure the temperature every 10-20 ingots and record it properly, so as to keep track of the temperature changes of the ingots and maintain normal extrusion temperature.

7. When squeezing, pay attention to the changes in pressure. When starting, the pressure should not exceed 210kg/cm2. During normal extrusion, the pressure will decrease with the process. If the pressure does not decrease for more than 1 minute after starting, the extrusion should be stopped to prevent damage to the equipment and mold.

8. The extrusion speed should be controlled based on the different characteristics of different alloys. Low impurity alloys can have a higher extrusion speed, while high impurity alloys can have a slower extrusion speed. If the temperature of the aluminum rod is too high, the extrusion speed should be reduced. If you want to increase the extrusion speed, the temperature of the aluminum rod should be controlled lower.

In order to control the mechanical properties well, the temperature of the discharge port must be ≥ 500 ℃.

10. First article inspection: The first profile extruded from the upper mold should have its material head cut 500mm long for mold repair as a basis. The first and second bars should be cut 500mm long and handed over to the inspector for appearance dimension and positional tolerance inspection to confirm whether they meet the requirements of the drawing size and assembly relationship, thus determining whether the mold can continue production.

11. In order to prevent aluminum sticking to the end faces of the mold, ingot cylinder, and extrusion gasket, it is allowed to apply a small amount of mold release grease on the end faces of the mold and gasket, but it should be applied as little or no as possible, and it is not allowed to apply it to the mold cavity and inner wall of the ingot cylinder to prevent grease from polluting the profile.

12. Use extruded gaskets correctly to protect them from damage. When the compression gasket is worn too much, becomes a rounded corner, and the cylinder cleaning is not clean, it should be replaced with a new gasket in a timely manner. During each extrusion, special attention should be paid to whether the gasket is properly placed to prevent equipment accidents caused by the improperly placed gasket.

During the aluminum extrusion process, attention should be paid to the changes in hydraulic oil temperature: when the oil temperature rises to about 45-50 ℃, the extrusion pressure will greatly decrease, and the extrusion opportunity will become weak. At this time, the machine should be stopped and efforts should be made to lower the oil temperature before starting the machine again for extrusion.

14. The tonnage of the aluminum profile extrusion machine is 60010001650, and the number of ingots extruded per mold set is 100-15060-8040-80.

15. In order to prevent the gas and dirt from entering the aluminum profile in the dead zone of extrusion and to protect the extrusion rod from damage, the length of the excess pressure should not be too thick or too thin, and the excess pressure should be controlled to a thickness of 15-30mm.

16.6063 Forced air cooling and T5 Free cooling shall be adopted for T6 quenching of extruded aluminum profiles, and the profile shall be cooled to below 170 ℃ at a rate of not less than 80 ℃/min. 6061 extruded profiles are quenched using strong wind, water mist, or direct water cooling methods, and the temperature should be reduced to below 200 ℃ within 2-3 minutes.

17. Aluminum profiles must be cooled to below 50 ℃ on a cooling bed before being straightened. When straightening profiles, the straightening amount should be controlled at around 1-2%. The straightening deformation of ultra thick profiles is allowed to be slightly larger, but it should not exceed 3%., When straightening, attention should be paid to protecting the decorative surface from scratches, and it is best to contact the conveyor belt of the scaffold with the non decorative surface.

18. Before sizing aluminum profiles, their length tolerance requirements should be clearly understood. If the customer has special requirements, they should follow the customer's requirements; If there are no special requirements, the length tolerance shall be controlled by+15mm. When delivering in multiples, the total deviation is+20mm. After calibrating the fixed length position, when cutting out the first profile, check whether the length meets the requirements. It must be a positive deviation and not a negative deviation. After confirming that there are no errors, start batch fixed length sawing.

19. To prevent scratches on aluminum profiles, do not stack and saw the profiles. When the profiles move forward, the aluminum shavings on the saw table should be blown clean first.

When sawing, the saw blade should be lubricated with oil, but it should be prevented from sticking to the surface of the aluminum profile. After 20 saws, the saw edge of the aluminum profile should be perpendicular to the axis, and the saw edge should be free of burrs, burrs, and twisted deformation. In order to have a beautiful saw blade, the sharpness of the saw blade should be regularly maintained, and attention should be paid to removing aluminum deposits on the saw blade. When the saw blade is not sharp enough, it should be replaced and polished in a timely manner or replaced with a new saw blade.

21. After sizing, the aluminum profile should be blown clean with compressed air and then framed.

22. After the aluminum profile is sized, the large materials are inspected one by one, and the small and medium-sized materials are randomly inspected at a ratio of 10%. The inspection content includes flatness, bending, torsion, opening, closing, and surface quality.

23. After the aluminum profile is sized and inspected to be qualified, it should be gently lifted and placed in the frame by two people, carefully arranged neatly, and not collided or rubbed with each other. When framing, clean gauze gloves should be worn, and the gloves should not contain oil, water, or other dirt. When framing, long and heavy materials are placed in the lower layer of the frame, while short and light materials are placed in the upper layer of the frame.

24. After placing one layer, according to the length of the aluminum profile and its degree of self weight bearing, 4-8 horizontal bars should be appropriately placed, and then the second layer of aluminum profile should be placed. Vertical bending and stacking of profiles are not allowed.

25. For solid aluminum profiles that cannot be ventilated longitudinally with fine materials, small square tubes with ventilation holes should be used to separate them in layers, in order to facilitate efficient ventilation and heat transfer.

26. The plane of the upper layer of aluminum profile should be lower than the plane of the material frame to prevent compression during frame stacking