The actual production, some dies fail to achieve the scheduled output in the extrusion processing , badly extruding less than 20 billets or less than 2 times then be rejected, as a resut,expensive die cannot bring its due benefits, which not only caused a lot of economic losses, but also a waste of energy, so to improve the aluminum extrusion die,you can do a good job from die statistical analysis and cost management.Below tips for you:
1,Polishing to mirror Dies before the working must be polished, die bearing should be polished mirror. The flatness and verticality of the mold work belt should be checked before assembly. The quality of nitriding determines the degree of polishing of the work with a certain degree of finish. Die cavity must be used to clean up the high pressure gas and brush, no dust or impurities in foreign matter, or easily driven by the metal flow under the work of the belt, so that the extrusion of the profile products appear rough or crossed and other defects.
2,Heating 2-3 hours Extrusion production die holding time is generally 2-3 hours, but not more than 8 hours, otherwise the die nitriding layer hardness will be reduced and lead to wear on the machine caused by rough surface rough, even cause crossed and other defects.3, Correct alkali washing method Using the correct alkali washing (boiling die) method. When die unload, its temperature is above 500 ° C, if immediately immerse in alkaline water, die maybe break. The correct way is to cool die in the air to 100 ° -150 ° C and then immersed in alkaline water.
4,Optimize the extrusion processing.
To scientifically extend die life , the rational use of mold production can not be ignored one aspect. As the extrusion die working conditions are extremely poor, in the extrusion production must take reasonable measures to ensure that the die's organizational properties.
5,Nitriding process Die must need to do nitriding process. nitriding treatment can improve die hardness.Nitriding treatment need more times,3-4 times is required,nitrding thickness should reach 0.15mm.
6, Control die working intensity The use of molds from low to high to low use of strength. When the die has just entered the service period, the internal metal structure is still in the floating stage, during which the low intensity operation plan should be adopted to make the mold transition to the stationary period.
7,Establish die maintenance records Improve the record of each set of die records and management. Extrusion die life from the acceptance to the life end , which is short in a few months, long for more than a year. Basically, the use of die records also records die working processing.
8,Select the appropriate extrusion press tonnage for productionBefore the extrusion production, the profile section should be fully calculated, according to the complexity of profile section, wall thickness and extrusion coefficient λ to determine the size of the press tonnage.
9,Reasonable die design Aluminum cross-section itself on the ever-changing, and the development of aluminum extrusion industry today, aluminum has a light weight, good strength and other important advantages, there are many industries have used aluminum instead of the original material. Due to the special profiles the die design and production are more difficult.
10,Choose good quality billet and control heating temperature
The alloy composition of aluminum billet should be strictly controlled. At present, the general enterprises require grain size of the ingot to meet the primary standard, to enhance the plasticity and reduce the opposite natures.
(Thank you Mr. Frederick Diekman,your contributions are very important.Below points from Mr. Frederick Diekman)
11. Shot peen before polishing.
Use progressively smaller shot during each shot peening. Start with 230 size, then go to 110, then go to glass bead shot.
12. Cryogenically treat after shot peening but before polishing.
This will make polishing faster and give you a better surface. It will also give you much more wear resistance. Use deep cryogenic treatment wit a slow reduction in temperature down to -300F, hold for a time appropriate for the metal, and do a slow increase to room temperature. Temper twice at an appropriate temperature.
