Analysis to increase aluminum production and extend extrusion die life

【China Aluminum Industry Net】 normal life of normal aluminum mold die before the normal failure of the mold, the number of qualified products produced, called the normal life of the mold, referred to as the mold life, the number of qualified products produced before the first repair of the mold, called the first life; The number of qualified products produced after a mold is repaired until the next repair is called repair life. Die life is the sum of the first life and each repair life.

Die life is related to the shape and structure of the mold. It is a comprehensive reflection of the mold material properties, mold design and manufacturing levels, mold heat treatment levels, and the level of use and maintenance within a certain period of time. The level of mold life reflects, to some extent, the level of a metallurgical industry and a machinery manufacturing industry in a region and a country.

The mold failure mode and mechanism but the failure form can be summed up in three ways: wear, fracture, and plastic deformation.

(1) Wear failure When the mold is in service, it comes into contact with the forming blank and generates relative motion. Due to the relative motion of the surface, the phenomenon of gradual loss of material at the contact surface is called wear. Wear failure can be divided into the following categories:

(2) Fracture Failure When the tool has a large crack or is separated into two parts and parts are lost to service, it becomes fracture failure. The fracture can be divided into plastic fracture and brittle fracture. The mold materials are mostly medium and high strength steels, and the fractures are mostly brittle fractures.

Brittle fracture can be divided into one-time fracture and fatigue fracture.

(3) Failure of plastic deformation The plastic deformation of the mold is the yielding process of the metal material of the mold. Whether plastic deformation occurs or not, the mechanical load and the room temperature strength of the mold play a dominant role. Whether or not a mold that is in service at high temperatures produces plastic deformation depends mainly on the operating temperature of the mold and the high temperature strength of the mold material.

With the development of aluminum industry trends, everyone has been seeking better and better development models in recent years to improve efficiency, save costs, and increase profits. The output extrusion die for aluminum profiles is undoubtedly an important control node. To increase its lifespan is of course a systemic problem. In the actual production and use process, general aspects such as optimization design, mold processing, and maintenance are generally used.

First, optimize the design For the extrusion die, the level of design directly affects the status of the discharge to a certain extent related to the life of the die. The design of the extrusion die is firstly to select a suitable extrusion ratio according to the profile conditions to determine the tonnage and the number of holes of the machine table, so that the designed diverting orifices form a state of discharging balance, and the stress concentration design should be avoided as much as possible. Construction, to make the various parts of the mold force to ensure its stability. The following is a brief description of some typical practical examples: For profiles such as (Fig. 1), the bridge position is usually designed to avoid straight punching in the design, because such molds tend to collapse.

The wall thickness difference between the two sides of the cantilever is generally designed as a high and low working belt (as shown in Figure 2). This can effectively regulate the flow on both sides and can avoid the collapse to some extent.

Some smaller forging tools are prone to yaw or break, and are usually designed as sub zero air knife (Figure 3), effectively increasing their strength.

For the foreman more complex screw holes and more foreman general upper empty knife will be properly lengthened, the purpose is to strengthen the screw hole position strength. In view of the fact that the heat treatment is better for the quenching dies, better stress release and better heating and thoroughness, boreholes will be added in the middle of some large square tubes and rectangular foremen (Fig. 4).

If the profile has a longer diagonal and a square pipe type, the thickness of the upper die will generally be thickened to better ensure its strength, and the bridge position will also be appropriately widened, thus effectively avoiding problems such as premature crack angles.

Second, the mold processing Extrusion die manufacturing is divided into mechanical processing and electrical processing. Basically, mechanical processing is rough machining, and the main structure of the mold is completed. Electromachining is the finishing process, and the main parts such as the working belt are mainly processed again. In order to increase the life of the extrusion die, it is important to note some details during the processing. In particular, through the situation after the rework, it is analyzed how the better processing can be performed when the next mold is added.

1. In terms of heat treatment, the hardness value of the general extrusion die is HRC47-HRC51, but for large die hardness values ​​of ¢560 or higher, the lower limit of HRC47 is generally taken. Because this can not only ensure the hardness of the mold but also maintain the toughness required by the mold.

2. For the processing of the diverging hole, especially the porous die, special attention should be paid to the symmetry after the diverging hole machining. The loss of the cutter should be taken into account in the machining process to ensure the final dimensional accuracy. Grinding work is to polish the mold, in the process of rough play must be knife marks, diversion, transition, etc. play well, all the bridge and the mold neck connection must arc, so better heat treatment . At this point, our company has made a substantial improvement in the surface finish of the mold in accordance with the process of hot roughing and hot playing, which is more conducive to the smooth discharge of materials and the reduction of friction.

3. Diversion plays an important role in the balance of feeding for extrusion dies, resulting in the processing of diversions becoming the focus of attention. The general diversion process is carried out according to the design drawings. However, in order to improve the on-time pass rate and to give full play to the advantage of on-site processing personnel, our company conducts general diversion and perforation processing based on the experience values ​​of field processing personnel (summarized from the normal mold rework condition).

4. The processing of the mold blank knife plays an important role in its strength, especially the empty knife at the top, end, cantilever, etc. Normally, to ensure its strength, the angle of the empty knife in the special part will be slightly increased and the value of the empty knife will be removed. In order to ensure that the mold does not produce excessive wall thickness as early as possible, the mold thickness is generally negative (0 to -0.03 MM).

Third, the subsequent use and maintenance of the mold 1. In the trial mode, the extrusion process should pay attention to the following aspects: A. Before the extrusion temperature rod temperature determination, whether to meet the extrusion temperature requirements, whether there is warming Transparent core (placement of the mold in the heating furnace is very important, there must be a certain warming gap between the mold and the mold). B. The extrusion die must be aligned with the center so as to avoid the phenomenon of collapse and plug. C. Use different extrusion speeds for different profile molds to avoid unsmooth discharging. D. We must also pay attention to the quality of aluminum rod during the extrusion process to avoid the occurrence of die collapse due to aluminum rod impurity problems.

2. Mold repair is a very important part, but the first thing to consider in repairing the mold is its strength. It is necessary to repair the mold on the basis of the strength of the mold. Less than the latter, welding is generally not used because the welding has a major influence on the life of the die. In particular, welding of the work belt can easily cause a shortened life. For the repair of profile speeds, it is generally faster to use slower speeds instead of slowing them down. At this point, the burden on the mold structure to a certain extent can guarantee its life. Of course, one of the ways to improve the service life of the mold is to increase the mold repairing level and reduce the number of test molds.

3. In the process of model sculpting, special attention should be paid to taking the blunt material, especially in some screw holes or more fragile places, otherwise, it is easy to smash the mold.

4. Carefully carry out the mold handling process, avoid bumping into the working belt and other places. Before the mold is put into the warehouse, be sure to clean it, carefully and thoroughly inspect the mold for fine cracks and breakage.

5. For the finished molds, it is necessary to manage the process data effectively, such as the mold repair program, the details of the processing, and the extrusion process. Because these can become the follow-up complementary mold or similar mold copy object, this can effectively improve the mold machine pass rate.

In short, the increase in the life of extrusion dies depends on the perfect link between design, manufacturing, use, and subsequent maintenance. Relying on a single link can not effectively achieve the goal. Through the effective integration of various links, it is believed that the mold life can be improved accordingly.

50mm EPS Sandwich Panels

polyurethane sandwich panel

polyurethane foam sandwich panel
1. Excellent price and quality
2.Light weight Sandwich Panel
3. Good quality Sandwich Panel

Eps Sandwich Panel,Pu Metal Decoration Panel,Insulation Metal Siding,50Mm Eps Sandwich Panels

Jinan Zhengtang Insulation Decoration Material Co.Ltd , https://www.ztwallsiding.com