Waste: an unwanted or unwanted substance or material (Wikipedia: online encyclopedia). To an outsider, looking at the metal smelting industry, it seems that the substances we most often waste are time and energy, and they may be right! In some foundries, these non-replaceable resources are wasted, not recklessly or intentionally, but because their design and production methods are based on outdated production processes.
Past engineering process
In the past, paper and pencil were the most important tools a foundry designer had, and developing a foundry was a tedious and time-consuming process. A design was created on paper; The project was presented to the Die Caster, who partnered with a tool maker. Together, a die casting machine was selected; the process and the mold design developed and the estimated costs. Appointments were made. The winner of the tender gave his tooling supplier permission to order die steel and begin mold design. When finished, the mold was sent to the foundry for a first test. After being incorporated into the machine, castings were made and imperfections checked.
It was not until this point in the process that those involved had any idea about the quality of the casting. If the casting did not meet the desired standards, changes would have to be made. Different process adjustments and small die corrections could be made on the die casting machine right away, but if the first test showed that the mold had to be changed, the steel had to be ground and welded elsewhere, and that job had to be done. to be necessary. performed at the tool supplier’s facilities. The mold traveled back and forth between the toolmaker and the foundry until an acceptable casting quality was achieved. The time between the start of the foundry design and the shipment of a good cast can take weeks, months or years, depending on complexity and size.
Also, mold designs could, and did, change even after production started, and those changes meant that molds could have different designs, different ages and usage patterns, and different casting qualities. In addition to mold changes, variations in production parameters such as die casting machine pressures, pour speeds and transitions, lubrication volumes and locations, solidification, and cycle times changed throughout. of the casting process. The never-ending need to adjust and improve casting ended only when casting was no longer needed. Working towards better casting quality kept a large team active with the participation of the process engineer, machine operator, mold maintenance and tool maker, quality office, casting designer, machining foundry, including assembly and planning and materials handling group.
While there was a time when this type of ‘engineering’ was necessary, today’s economic realities make it financially unfeasible to continue in this way, but still, this ‘engineering’ can be found in companies that are struggling to break through. in difficult situations. times.
“The capacity of the die casting industry in the US was reduced … with the closure of plants that could not keep up with technology …” Daniel L. Twarog, President of NADCA, letter from editor, LINKS, February 2009
Process optimization today
With the addition of computers to factories, the engineering process is continually changing and simplifying. Casting is no longer drawn on paper and tool dimensions no longer have to be transformed into mold drawings. Computer-aided designs available in three-dimensional volume models allow information to be transferred with the push of a button and used as input directly into steel machining equipment. Changes to models can be made quickly and easily and shared with all design departments.
The great value of computerization lies in the opportunity to develop, design and build almost at the same time. These parallel working conditions reduce development time and accelerate ‘time to market’ to a level not even dreamed of years ago. Computerization within the engineering and manufacturing process has also enabled more precise machining equipment in tool shops, custom die steels, and heat treatment processes that allow changes based on factors such as: production cycle length and material in direct contact with the melt or for the better. heat transfer and heat flow.
One of the biggest changes has occurred in the field of process improvement. With MAGMASOFT (r) simulation software, the entire casting process can be simulated, changed and optimized in the short period of time available to the toolmaker. Simulations made of cast iron models provide information on the quality to be expected during cast production, prior to launch. Based on the simulation results, you can easily make changes to the casting, channel system, mold, or process parameters and quickly review the results.
Similarly, casting can be optimized to fill better and solidify more uniformly, avoiding porosities; the channel system can be modified to reduce the amount of trapped air, which leads to porosity; the internal cooling design is developed to minimize solidification times and allow for faster production cycles, and simulations that include stress calculations can be used to predict die life, cracked castings, or distortions. Consistent use of MAGMASOFT (r) during casting and process development creates good castings and stable processes from the first die test onward.
Additional adjustments during casting production are only on a minor scale and should not change the mold or the casting design at all. The result is a cast, mold and process design that can be used until castings are no longer needed, significantly reducing design and production time and costs. Reducing the time and effort involved in the design and production areas allows the improvement team time to focus on other important tasks, such as the effects of different die steels or better heat treatment to extend the life of the dies. , implementation of more sophisticated equipment to increase the opportunity to mold more complex castings or save fusion energy, increase automation and educate workforces, and all this without disrupting good production.
Committing to these changes leads to greater competitiveness and strengthens the position of the industry in the world market.
“The optimization has the potential to significantly amplify the usefulness of the simulation and the simulation results for launchers.” R. Allen Miller, Computer Modeling Worldwide Literature Review, LINKS, February 2009
More time and energy to save
The area that can be least improved is that of human work speed. Computers run hundreds of times faster than they did years ago, but that’s a transformation humans can never duplicate. However, unlike machines, humans are intelligent and capable of using those software and hardware enhancements to our advantage. Yes, getting out of the office, flying into a meeting, having a great lunch, and staying in a good hotel is great, but in most cases it is also inefficient and a waste of time and money. Today, with easy access to the Internet, industries have the availability of email, ftp, conference calling, or web, and those technologies are making their way into the engineering process. Gone are the times when people had to drive for hours for a short meeting or travel abroad to visit foreign sources. This is not to say that the designer, the caster, and the toolmaker should not know each other, but at a time when engineering has been reduced to a basic product and available globally, the personal, “one-on-one” visit. , it will be reduced. or even removed.
With the ever shorter time frame allowed for engineering, development, construction and implementation, process travel time is no longer feasible or economical. That time is necessary to work on the project. Every day on hold can jeopardize the delivery date. Sending large digital files over the Internet can take a few hours, but once transmitted, they are instantly available for a web conference. However, some businesses still require face-to-face meetings to evaluate results, wasting time and money for almost all participants. But the biggest waste of time hasn’t even been discussed yet. This is the hesitation when making decisions on the part of the buyer to place the project order. Even when casting and tool supplier quotes have been made in a timely manner, company finances or policies may require a second or third round of quotes in an attempt to save an additional dollar here or there.
Even when the total ‘time to market’ is severely limited, more than half of that time can be spent on the selection process to take up to four months, resulting in insufficient time for the caster and toolmaker. to create a process. build the die and deliver good castings. Buyer hesitation in determining a source reduces available engineering time and can add significant costs to the process, canceling out any short-term savings with additional production costs and time-to-market delays. As long as a department only looks at direct costs and does not consider the total cost of casting, the project never realizes its full financial potential for the company.
Summary
Streamlining the high pressure die casting engineering process can save a lot of time and energy, which will be seen as a huge money saver. With up-to-date computer equipment and software, travel times and costs can be greatly reduced, while communication can be made faster and more effective. Making faster decisions for sources will give engineers more time developing more stable processes that produce better castings. By adopting available technologies, companies can conserve their irreplaceable resources (time and energy) while at the same time being more efficient and, most importantly, in this economy, more profitable.