Analysis on the Use and Maintenance of Aluminum Alloy Profile Extrusion Tool and Die

(1) Use advanced instruments to detect the dimensional accuracy, hardness and surface roughness of the mold online and offline. The molds that pass the inspection and acceptance are registered, put on the shelf in the warehouse, and the polishing mold hole working belt is taken out when used, and the guide mold, profile mold, and mold pad are assembled and checked, and sent to the machine for heating when they are confirmed to be correct;

(2) The heating temperature requirements before the tool and die are put on the machine: extrusion cylinder: 400～450℃, extrusion pad: 350℃, mold cushion: 350～400℃, flat die: 450～470℃, split die: 460～480℃, the holding time is calculated according to the thickness of the mould (1.5～2 minutes/mm);

(3) The heating time of the mold in the furnace is not allowed to exceed 10 hours. If the time is too long, the working belt of the mold hole is easy to corrode or deform;

(4) At the beginning of extrusion of aluminum alloy profiles, pressure is slowly applied because the impact force is likely to cause mold blockage. If mold blockage occurs, stop the machine immediately to prevent the mold hole working belt from being crushed;

(5) After the mold is unloaded from the machine, it will be cooled to 150～180℃ and then put in the caustic tank for cooking, because the mold will be easily cracked by the impact of heat waves when it is boiled in alkali at high temperature. And should adopt advanced corrosion washing methods to recover and save lye, shorten the corrosion time and realize pollution-free cleaning;

(6) When assembling the split mold, the mold repairer should use a copper rod to lightly hit, and it is not allowed to hit with a big hammer to avoid excessive force and shake the mold;

(7) Before mold nitriding, the working belt of the mold hole must be carefully polished to the surface roughness Ra0.8～0.4μm;

(8) The mold must be cleaned before nitriding, and oil stains are not allowed to be brought into the furnace; the nitriding process must be reasonable (depending on the characteristics of the equipment and the mold material), and the surface hardness after nitriding is HV900～1200, nitrogen Too thick and hard coating will cause the nitride layer to peel off. A set of molds generally allow nitriding for 3 to 5 times; the nitriding process is not carried out for the complex high-magnification radiator profile mold;

(9) Nitriding treatment can be directly applied to the new molds, rod molds, and round tube molds of old products without trial molds; new products and complex profile molds must pass the trial molds before they can be nitrided;

(10) After the new mold test is qualified, up to 10 ingots should be squeezed and the machine should be unloaded for nitriding to avoid pulling the working belt out of the groove; excessive production is not allowed between the two nitriding, generally flat The mold is 60-100 ingots, and the split mold is 40-80 ingots. Too much will pull through the nitride layer.

(11) After the used molds are polished, they should be kept in a warehouse.