1. Die casting process
1.1 Die casting process introduction
What is die casting? As we metal casting companies all know, it is a kind of metal casting process. Furthermore, using the mold cavity to apply high pressure to the molten metal is a property of die casting process. Generally speaking, the die casting mold is made of a alloy with higher strength. And this process is somewhat similar to injection molding process. Certainly, there is difference between die casting and injection moulding of metal parts.
The die casting equipment and die casting molds are expensive. Therefore, metal castings factory only uses the die casting process for mass production of a large number of metal products. Above all, it’s relatively easy to make metal parts. In general, it takes only four major die casting process steps. And the single step cost increment during die casting manufacturing process is very low.
Die casting process is particularly suitable for the manufacture of a large number of small and medium sized castings. Therefore, mold die casting is the most widely used one in various metal casting process. While comparing it with other alloy casting, it has a flatter surface and a higher dimensional consistency.
1.2 Die casting process steps
The high precision die casting uses high pressure to force metal melt into a complex shaped metal mold. Because Xuzhuo Industrial is a professional die casting manufacturer. And we use the traditional precision die casting, which has only four steps. Certainly, these four die casting process steps include mold preparation, filling, injection, and falling sand. Also, they are also the basis for various modified premier die casting processes.
In the preparation process of high pressure die casting, we need to spray the lubricant into the cavity. And the lubricant can help to not only control the metal mold temperature, but also release the die casting mould. Furthermore, the operator closes the die casting mold. Then we use the high pressure die casting to inject the molten metal into the mold die casting. In general, this pressure ranges from 10 to 175 MPa.
When we fill the molten metal, the pressure is maintained until the pressure die castings solidify. Next, the operator uses the pushrod to roll out all the gravity die castings. Therefore, there maybe are many pressure die castings during each die casting process. The sand falling process requires the separation of the residue, including the die casting mold making port, the runner, the gate, and the trimming. Furthermore, we usually finish this process of die casting step by step. And a special trimming die extrudes the gravity die castings, then we finish this die casting process step.
1.3 Die casting machine
According to the different types of die casting, we need to use cold chamber die casting machine and hot chamber die casting machine. And the difference of these two kind of die casting machines is the power they can bear. In general, the typical pressure range is from 400 to 4000 tons.
Advantages of hot chamber die casting include these three aspects. Firstly, the cycling speed of hot chamber die casting is fast, and it can finish 15 cycles for each minute. Secondly, it’s easy to realize the automotive operation for hot die casting. Thirdly, the metal molten process of hot chamber die casting is convenient. Similarly, there are also disadvantages of hot chamber die casting. On the one hand, it can’t cast metal with high melting point. Certainly, hot chamber die casting machine is used for zinc, tin, lead and die casting alloys. On the other hand, hot chamber die casting applications don’t include large metal products. Generally speaking, die casting companies use the hot chamber die casting for producing small castings.
While, we adopt cold chamber die casting for metals which can’t use hot die casting. For example, cold die casting applications of aluminum, magnesium, copper, and zinc alloy with high aluminum content.
In most cases, the advance die casting does not need lathe work, and can directly assemble. Even more, threaded metal parts can be casted directly. Finally, application of die casting includes small die casting needs of camera metal parts, typewriter metal parts, electronic computing devices and decorations. What’s more, it also includes complex metal parts of vehicles, locomotives, aircraft and other means of transport.
1.4 Advantages of die casting
Die casting process advantages include the following three aspects.
Firstly, good quality of die casting products. As we die casting companies all know, the precision die casting is pretty high. In general, it’s 6-7 grade, and can even be 4 grade. And metal products with die casting method have a good surface smoothness. Furthermore, it has high strength and hardness. And compared with common metal castings, the strength of metal die casting is 25%-30% higher and ductility is 70% less. Finally, its dimension is stable, and we can use the die casting tooling to produce complex and thick-wall castings.
Secondly, high production efficiency. China cold chamber die casting machine that we Xuzhuo Industrial has can die cast 600-700 times for each 8 hours. And small hot chamber die casting machine can die cast 3000-7000 times for each 8 hours. Furthermore, die casting parts have long service life. Finally, it’s easy to realize automation and mechanization for top die casting.
Thirdly, good economic effects. Because the pressure die castings have advantages of precise dimension and smooth surface. In general, there is no more mechanical processing and we directly use it. Or the quantity which need to process again after the mold die casting is a few. And then it not only increases the using rate of die casting materials, but also reduces the amount of processing equipment and working hours.
2. Die punch
2.1 Die punch definition
The metal punch machine and metal mold apply external force to rolled plate steel, strip, pipe and steel rolled sections. And then the material used for die and punch will produce plastic deformation or separation. Later, metal stamping die manufacturers get the required shape and dimension punch and die set. This is the whole process of die stamping press.
Both stamping die and metal forging are pressure forming. And the material used for die and punch is mainly hot rolled steel VS cold rolled steel. As punch and die manufacturers all know, the 60%-70% of the world rolled steel are panel. Furthermore, most of rolled steel sheet is made into finished products by metal punch press. The application of punch and die includes car body, chassis, fuel tank, and radiator fin. What’s more, the shell of the container, motor, electrical core silicon steel sheet and so on. And there are also many stamping die components among instruments, household appliances, bicycles, office machinery, and household utensils.
First of all, punch company uses the power of general or special punch press. Then, the sheet metal stamping dies are directly deformed in the metal stamping dies. Finally, we get the metal parts with certain shape, dimension and performance. As a result, this is the whole progressive die stamping process. Furthermore, sheet, mould and equipment are three elements of die stamping process.
According to the different progressive die stamping temperature, punch press dies suppliers divide it into hot metal stamping die and cold metal stamping die. The former is suitable for processing sheet metal punch dies which have high deformation resistance and poor plasticity. Likewise, the latter works at the room temperature, and it’s a commonly used method of metal stamping dies.
2.2 Die punch introduction
The mold used during the stamping process is called stamping die. And the metal stamping dies are special thermoforming tools which batch thermoforming materials into required metal stamp dies. Above all, metal stamping dies are pretty important for die stamping process. On the one hand, it’s hard to go on the batch stamping production with no metal punch dies to meet the requirement. On the other hand, we can’t make the advanced die stamping process come true. As we all know, punches and dies engineering, punch dies press and punching materials constitute three elements of stamping process. Only when these three elements combine, and punch dies suppliers can get the die punch set.
When comparing the stamping die components with die casting parts and forging metal parts, they have characteristics of thick, uniform, light and strong. Also, it can produce molded parts with reinforcing rib, costal region, ups or downs to improve its rigidity. Because we use high precise die mold, the precision of stamping die components can reach micron level. Also, it has high repeat precision and consistent specification. Generally speaking, we no longer machine metal hole punch dies or they only need a small amount of machining. While, the precision and surface state of hot die punches is lower than cold die punches. Of course, it’s still better than casting part and forging metal parts.
2.3 Die punch characteristics
2.3.1 High efficient production method
Stamping process is a kind of efficient die production method. And we usually use compound die and progressive die. Especially for the multi-position progressive die, punch press dies suppliers can finish multiple stamping process on one punch press machine. Furthermore, punch company can make the full automatic production of stripping, flattening, blanking to forming and finishing during progressive die stamping progress.
The progressive die stamping has properties of high production efficiency, good labor condition and low production cost. Generally speaking, punch and die manufacturer can produce hundreds of progressive die for every minute. Compared with other methods of mechanical and plastic process, punching process has many advantages. What’s more, it not only shows the advantages in the aspect of technology, but also economics.
2.3.2 Four die punch characteristics
Firstly, the stamping process has high production efficiency, convenient operation and is easy to realize mechanization and automation. As we punch and die manufacturer all know, this is because stamping process is accomplished by stamping die and punch press machine. Ordinary punch machines trips can reach dozens of times per minute. Also, high speed punch press machines can reach hundreds of or even thousands of times per minute. Furthermore, we can get a punch press die for each die punch trip.
Secondly, the stamping die ensures the shape and dimension precision of stamping die components. In general, it won’t destroy the surface quality of punches and dies. And the service life of metal mold is long. Therefore, the metal stamping die has a stable quality and good interchangeability. Even more, hole punch die has the feature of “all the same”.
Thirdly, with the die stamping process, punch dies suppliers can produce die parts of large dimension range and complex shape. For example, small to the stopwatch, big to auto girder, cover piece and so on. When we add the punch, the die material cold deformation hardening effect, strength and rigidity are high.
In general, there is no chip broken material produced during the stamping process. And the consumption of thermoforming materials is little. What’s more, it doesn’t need any heating equipment. Therefore, it’s a kind of provincial material, energy-saving processing method. Finally, the cost of punch die set is low.
2.4 Die punch application
It has so many advantages of making a metal stamping die. Therefore, we use the die stamping process widely in various fields of national economy. For example, there is punching process in aerospace, aviation, military industry, machinery, agricultural machinery, electronic, information, railway, telecommunications, transportation, chemical, medical equipment, daily appliances, light industry and other departments.
Not only is it used by the entire industry, but everyone has direct contact with metal stamping die sets. Such as planes, trains, cars, and tractors, there are many punches and dies on them. Also, the auto metal parts of body, frame and ring are all produced by die punches. Then, 80% parts of bicycles, sewing machines, and watches are metal stamp dies. And 90% parts of television, radio, and camera are punches and dies. What’s more, food metal can shell, molten steel boiler, enamel bowl and stainless steel tableware. They are all stamping products using metal mold.