Factors determined by the mold designer:The profile extrusion mold designer must consider the structure of the aluminum profile extrusion press, the selection of the mold machine, and the customer's product surface requirements and usage conditions. The complexity of the product drawing, the structure and dimensions of the mold, the mold material, the number of die holes and the extrusion coefficient, the extrusion ratio, the shape, size and allowable tolerances of the product, the shape, orientation and size of the die hole, and the size of the die hole Shrinkage, deformation deflection, strength and deformation, performance ratio, ratio of sizing belt to obstructed velocity, split flow, etc.
Mold manufacturing includes turning, milling, drilling, grinding, beating, cutting, polishing and welding. The accuracy of mold size and shape must be based on drawings. Main parameters: the processing accuracy of the profile sizing belt and the barrier system, surface finish, heat treatment hardness, surface carburization, decarburization and surface hardness changes, end-face parallelism, etc.
Quality factors affecting extrusion productionMold assembly and support, heating temperature of ingot, mold and extrusion cylinder, extrusion speed, process lubrication, product variety and batch. Alloy and ingot quality, traction condition, tensile strength and stretching amount, specifications of extruded alloy ingot. The cooling condition of the product exit, the neutralization of the mold, the control and adjustment of the industrial aluminum extrusion press, the setting of the guide path, the length of the output table and the straightening machine. The capacity of the industrial aluminum extrusion press and the specific pressure of the extrusion cylinder, the length of the residual material of the extrusion, etc.
The material of aluminum extrusion die is H13 steel. The mold can be used after nitriding. The whole set of mold is composed of three parts: positive mold, mold pad and mold sleeve. The following focuses on the structure of the positive model.
1. Working belt
The cavity size functions, the working belt is perpendicular to the working end face of the mold and forms the shape of the profile. The length of the working belt is too short, and the size of the aluminum profile is difficult to stabilize. If the working belt is too long, it will increase the friction of the metal, increase the squeezing force, and easily bond the metal.
2. The position of the blank knife of the profile mold
Ensure the extrusion of the profile, ensure the quality of the aluminum material and the life of the die.
3. Deflector (groove)
Set a transition shape between the aluminum rod and the aluminum product to reduce the deformation process.
4. Diversion hole
The passage, shape, cross-sectional size, number and different arrangement of aluminum material through the hole directly affect the quality of extrusion, extrusion force, and life. The number of shunt holes should be as small as possible to reduce the welding line, increase the area of the shunt holes, and reduce the extrusion force.
5. Die shunt bridge
Its width is related to mold strength and metal flow.
6. Mold core
Determine the size and shape of the cavity.
7. Welding room
A place where metal gathers and is welded together.
In addition, whether the mold structure design is reasonable depends on its split ratio and extrusion ratio.
Extrusion split ratio: The ratio of the cross-sectional area of the split hole to the cross-sectional area of the profile directly affects the size of the extrusion resistance, the forming quality and the welding quality.
Extrusion ratio: The ratio of the cross-sectional area of the extrusion cylinder to the cross-sectional area of the profile is one of the important parameters to measure whether the profile is suitable for production on the extruder.