Introduction of several molding methods in the mos

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Several modeling methods in modern mold casting during the period of China, the modeling methods adopted by foundry factories now have made great progress in modeling technology without major changes in the past decade. Wet sand molding, precision sand molding and lost foam casting are described as follows

1. Wet sand molding method. Mount company believes that among the molding methods applicable to most metal materials and mass production, clay wet sand molding is the most economical molding method. If the foundry is equipped with the latest technology control device, it should be done step by step. The best performance can be obtained repeatedly with the green sand control technology. These control devices include screening and separating metals, stable operation of cold domestic coke market of recycled sand, accurate release of additives during mixing of recycled sand, etc

vulcan company believes that the current clay wet sand molding machine has excellent performance, and can manufacture wet sand molds at a speed never reached two years ago, with strict requirements and little difference allowed. In addition, the sand supply device with accurate control and high efficiency keeps the clay wet sand mold in the most important position in the modeling of iron-based alloys and non-ferrous alloys

macler Assoc believes that in wet sand molding, vertical parting and horizontal parting are compared. For large-scale production of small and medium-sized gray iron or ductile iron castings, heavy direct parting molding is advantageous because of its advantages such as low equipment cost, high-speed molding, less personnel required, and small deviation of compactness. However, the vertical parting process is limited in the gate scheme, gate shape and shape, as well as the use of complex cores, filter sheets, chills, casings and pounding cores. In addition, when the alloy with good fluidity is used for casting, due to the high static pressure of metal, it is easy to cause metal penetration and sand sticking

in the manufacturing of non-ferrous alloy castings, a vertical parting molding method suitable for mass production of such alloy castings with various characteristics has been designed and is now being popularized. However, for castings with required mechanical properties, as a production method of large-scale aluminum alloy castings, the metal mold casting method still has an advantage before reaching a high degree of mass production with this modeling method

macler Assoc believes that the horizontal parting wet sand casting method is one of the favorable molding methods for medium and small batch casting plants. Whether it is the upper mold, lower mold or double-sided formwork, it is adaptable to the production of complex castings. The pattern can be changed within a cycle period, and the production can be effectively carried out in both short-term and long-term operation. However, the manual operation needs to be mechanized. In order to ensure the production of castings with good surface and high dimensional accuracy, the whole set of equipment needs to be transformed. For the selection of warm sand molding method, the following points should be considered:

◆ there should be molding equipment capable of molding high-quality molds with uniform hardness

◆ the template can be replaced quickly

◆ mechanized loading and unloading of lower core and mold

macler Assoc said that in order to make the modeling degree uniform, a variety of technologies were adopted. Several automatic double-sided formwork machines adopt sand shooting and compaction methods. At this time, in order to obtain uniform mold density, sand shooting and compaction methods are adopted. At this time, in order to obtain uniform mold density, the direction of sand shooting should be perpendicular to the plate. There is also an upper molding machine and a lower molding machine. In order to make the mold density uniform, micro vibration is also adopted. With the automation of modern production equipment, the level of compaction and compaction is getting higher and higher. In addition, in order to have strong impact when filling sand to the pattern, high compressed gas is also used. However, in order to obtain uniform mold hardness, a variety of methods have been adopted, and one method cannot be solved for various molding methods. In the selection of molding machine, we should investigate the foundry currently in use, and test with our own pattern to observe the results

◆ precision sand mold

the key point of this molding method is to use the chemical bonding mold of the cold box method. Vulcan believes that this is the revival of the casting process of aluminum alloy cylinder block and cylinder head. The reason is that this method can cast the cylinder liner in the cylinder block. At the same time, it also has the advantage of using cold iron to realize directional solidification. This method appeared in the 1970s and is used for casting near net shape castings and castings with complex shapes that need to add cores by wet sand casting. Now, when casting accurate castings with complex shapes and sizes, the standard method is to use the cold box molding method. Moreover, it is suitable for more alloys than sand casting. In the core making operation, it can be seen that due to the innovation of resin chemistry and molding device, the casting quality can be reduced at a lower price, and the automatic production line of liquid pump and manipulator for parts and components can be further improved, the labor required can be reduced, and high-quality and low-cost castings can be produced. The cold box molding machine is a major variant of the core making machine. Some molding machines shape the upper mold and the lower mold at the same time, and some molding machines can produce mold stacking casting with two cavities. The third variant is to use two sets of molding machines, one for the upper mold and the other for the lower mold

in order to improve the accuracy and minimize the flash of the parting line, these molding machines are characterized by tightening the casting mold to nb5.19 in the whole process. Large molding machine is completely driven by oil pressure in order to make its action smooth and reliable. It is equipped with a manipulator to carry out coating, drying, core lowering, adhesive coating and box closing. With these devices, the required labor force can be reduced to ensure the highest quality and production efficiency. The mold condition of this cold box molding machine not only affects the surface quality and cleaning operation of the casting, but also affects the correct assembly of the core and the position where the core makes the molding sand fluidized in the sand shooting head. Therefore, the design of the mold is very important

macler Assoc said that the cold box molding machine has several sand shooting technologies. Most of the molding machines, this type of molding machine, use low pressure and large air volume to shoot sand. After each cycle, it can shoot sand. There are two or three machinery factories that do not fluidize the sand, but use the extrusion method, use the patented sand shooting, low air volume and high pressure sand shooting. Some machinery factories believe that the sand is also easy to flow when making complex molds by extrusion. It is better to try and compare these two techniques with your own appearance to select the best method

the cold box molding method can produce complex molds with very accurate dimensions, but the mold cost, sand binder and catalyst cost are higher than those of the sand and binder used in the green sand mold, and the molding speed of the cold box molding method is low

lost foam casting mold

vulcan lost foam casting has developed due to the improvement of equipment and raw materials, and the rate of adoption is expanding. New technologies such as multi-directional filling working point and immediate filling of filling sand (follow-up sand) have improved the casting quality and molding speed while reducing the cost

the advantages of lost foam casting are: the foaming mold can have no slope or very small slope. Sometimes, the slope can be used to make complex shapes shape, and there are degrees of freedom in design. In addition, the weight of castings can be reduced, even without machining, and castings can be made without cores. The innovation of equipment and the new development of components, coatings and filling media have improved the casting quality and production efficiency, thus expanding the market

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