Metal Casting Zone Info Blog

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Every day in our lives we use die casting material but are completely oblivious to the process that is in place. Thousands of manufactures use this die casting to come up with daily items such as toys for children and even equipments that change our very method of working. Die casting has certainly provided the human race with a plethora of products that are incorporated into major appliances and automobile industry.

Conceptually, casting is a manufacturing process and requires articulate calculations to create the required outputs. This process injects liquid material into different moulds to solidify the mould. The amalgamation results in different fabricated parts. The primal benefit of casting process allows manufactures to create specific parts that are not economically feasible to create on the general assembly line. Million of parts that are made via die casting process could not have been achieved otherwise since the cost of producing certain items are not economical or even production possible. Any form of casting is a labor intensive process that requires a specific skill set. All processes from temperature building, quantity and quality of the liquid to be injected, form and shape of the mould, to the coolness technique of the output products all require specific skill sets. Without an accomplished team, it become very difficult for die casting manufactures to delivery quality products.

Die casting is a similar process in which molten metal is put under high pressure into the cavities of steel molds. The molds are called dies. The dies also come in different shapes and varieties in properties. Die casting process is heavily used in the automotive industry to create different body parts. Australia’s auto industry supports a large local die casting business, manufacturing parts that include cylinders, pistons and engine sumps etc. A very similar growing industry also flourishes in Korea as well since Korea is home to a large number of automotive manufactures. Die casting is one of the most efficient means of producing car parts since it is more feasible than the older versions of liquid casting and other strenuous techniques. Die casting has allowed for the substantial growth in mass production of automotives as well as parts for airplanes and trains as well.

Flourishing economies of scale also come with its price and challenges. Mergers and alliances are now a common practice in die casting manufacturing countries to streamline and hone processes to cater to the booming economy and mass productivity requirements. The die process entails four major steps that are required to be followed sequentially. The first step is to spray the mold with any form of lubricant and then close the mould. Different lubricants are used as per the requirement of the finished good. There are several benefits of using lubricant in the process. The lubricant both helps control the temperature of the die and it also assists in the removal of the casting. Effective lubricant can be the differentiator factor of average versus customer centric products. Molten metal is then injected into the die under high pressure. The high pressure assures a casting as precise and as smooth as the mold. This stage requires extreme caution in regarding to the pressure and checking of any defects in the mold. Once the cavity is filled then the pressure is maintained until the casting has become solid (though this period is usually made short as possible by water cooling the mold). There are also different ways of cooling the mold water cooling being one of them. It typically takes a lengthy amount of time to cool down the molds if left simply to nature. In order to expedite the end product, different cooling techniques are used. Finally, the die is opened and the casting is ejected. This is the entire process of the die casting procedures.

The clamping efficiency defines the quality of the machines that are used in the die casting manufacturing process. Typical sizes of the die casting machines range from 100 to 4,000 tons. Along with the massive weights also comes a gigantic size associated with the machines. Majority of the machines can be as large as regular home sizes in any city of the world. Irrespective of size, there are primarily two types of categories of die casting machinery. One is the hot chamber machines for zinc, magnesium and lower melting-point metals and the other is the cold chamber machines for aluminum (http://automobile.dmc.co.kr/eng/Aluminum-Die-Casting-Manufacturer.asp ) and higher melting-point metals. A die casting machine automatically opens and closes the mold and injects the liquid metal, all under high pressure and as rapidly as possible, in the case of zinc up to several hundred times an hour. This time line is also dependent upon the machinery features and the vendor. Extensive research and work has taken place to hone the die casting manufacturing machine features and make it more simple and cost effective both in terms of pricing and productivity. There are several key milestones that all die manufactures are looking anxiously to reduce. Time to produce the end product, minimize quantity of goods used in the entire process and enhance the overall skill set of individuals are all the key elements that need improvement. The anticipated reduction is approximately 30% – 40%, but the overall reduction is around 20% and that too in the human resource department. Engineers are now being trained on specialized avenues in die casting which helps in reducing the overall human resources required.

One of the ongoing challenges with die casting is detecting surface and sub surface defects within specific timelines. Defects and variances in the final products are still on the high end. Due to the high number of defects and variance, a large amount of raw material is lost and put forth as waste. Vendors have realized this gap in identifying the defects and variances during the process. Fully automatic machines are now being manufactured to cater to this ongoing challenge. A fully automatic fault detecting machine named CAST vision has been produced and a prototype process is in place for extended in-plant on-line trials. This is the third year of this project and it is giving good results. The result of algorithm which was designed and developed in 2nd year has been put to test now. By prototyping the CAST team had designed and developed a working system CAST vision. This can discriminate between good and defective parts.

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