Extrusion Aluminum's mold maintenance method

Extrusion Aluminum is to put aluminum ingots into a container and apply a certain pressure to form profiles of various shapes through the die holes. This container is an appliance made of steel, which is also called a mold. In the process, the quality and size of the mold directly affect the quality of Extrusion Aluminum. Because the mold will continue to wear under the harsh environment of high temperature and high pressure, the daily maintenance of the mold is very important.

The current market competition of Extrusion Aluminum is very fierce, and companies are doing everything possible to manage the use and maintenance of Extrusion Aluminum's molds in order to reduce production costs, because mold costs account for 35% of profile extrusion production costs. Although the mold has high heat resistance and wear resistance, due to the high friction frequency of the mold, the service life of many molds is very short, and the scrap rate is quite high, which causes great economic losses to aluminum profile manufacturers. In response to this phenomenon, how should we pay attention to the use and maintenance of Extrusion Aluminum molds in daily production?

In order to extend the service life of Extrusion Aluminum's molds, we have to proceed from the following aspects:

1. Nitriding treatment should be carried out before the mold is used. The purpose is to ensure the toughness of the mold, increase the hardness and wear resistance. A mold must undergo nitriding treatment 3-4 times in its lifetime, not more than 5 times, otherwise it will easily cause a working belt Delamination. The specific operation is the first nitridation of the qualified mold; the second nitridation after extrusion of 5-10 aluminum rods; the third nitridation after the second extrusion of 40-80 aluminum rods, and the third nitridation After that, 100-120 aluminum rods can be extruded, and the thickness of the nitride layer must reach 0.15mm each time.

2. The working belt should be polished before the mold is put on the machine. The quality of the front nitriding will affect the polishing finish of the working belt. Blow the dust and debris in the mold cavity with an air gun or clean it with a brush to prevent the aluminum alloy from straining the work belt when it flows, causing scratches on the surface of Extrusion Aluminum.

3. Pay attention to the correct cooking method. Do not wash the mold immediately in alkaline water, because the temperature of the mold is as high as 500°C, which is much higher than the temperature of alkaline water. Put it in alkaline water immediately to cool down quickly , But it can also cause mold cracking. After unloading the mold, the temperature of the mold should be naturally reduced to 150°C and then rinsed in alkaline water.

4. The holding time of the mold is within the range of 2-3h, not more than 8h. Too long time will cause the hardness of the nitride layer of the mold to decrease, resulting in poor appearance such as Extrusion Aluminum surface roughness or scribing.

5. Strictly control the alloy composition of the aluminum ingot and optimize the extrusion process. When the mold is just put into use, because the internal structure is not stable, the strength should not be too high. It must first transition from low to high for a period of time, and then The strength is reduced from high to low to extend the service life of Extrusion Aluminum molds.

6. According to the cross-sectional shape and complexity of Extrusion Aluminum, select the appropriate tonnage of the extruder. When selecting, it should be calculated according to the wall thickness and extrusion coefficient of the profile to determine the tonnage of the extruder. The cross-sectional shape of many profiles is very complicated. , Causing great difficulties to the design of the mold, if it is not planned in advance, it will increase a lot of unnecessary work and even cause economic losses for the enterprise.

7. From the time period from mold acceptance to use to scrapping, it is necessary to make various records and establish a corresponding file for each set of Extrusion Aluminum molds. The service life of each mold is different. Record the various molds during the service period. This use and maintenance situation also reflects the production situation of Extrusion Aluminum from the side.

8. After the production of Extrusion Aluminum has finished using the mold, the inside and outside of the mold cavity should be cleaned, oil and dust should be removed, and the label should be recorded and stored for next use.