How to improve the quality of mold processing through tools and chucks

With the rapid development of my country's automobile industry and mold industry in recent years, automobile panel molds have also developed rapidly in my country. Therefore, the gap between the level of some high-end molds in China and foreign countries is narrowing, and the middle and high-end car molds are all dependent on imports. It is also gradually being changed. The development cycle of new models has been shortened from the past 10 years to 2 to 3 years. All this is due to the improvement of equipment level and processing technology, plus the improvement of personnel quality and some new technologies. Applications. However, the automotive panel mold directly affects the appearance quality of the final automotive product, so how to ensure and improve the quality of mold processing by selecting suitable tools and chucks is particularly important. This article will discuss from the perspective of tools.

Selection of knife bar and blade

In today's mold industry, with the increasing pressure on the delivery cycle, it is very important to choose the best cutting tool. For the finishing tools of automobile cover molds, the indexable inserts with cemented carbide tool holders are generally used (Figure 1). In addition, depending on the mold shape and processing area, a tool with a diameter of 20mm or 25mm is generally selected.

There are many cast iron materials commonly used in drawing dies for automobile panels, such as HT300, QT600, MoCr and MoV, Japanese TGC600, FCD250 and FCD540, and GGG70L commonly used in German cars. The general material hardness is about 40HRC, plus The processing area of u200bu200bthe surface of the automobile cover mold is often large, so the selection of the blade is mainly based on the wear resistance.

As a tool supplier, Sandvik Coromant has successively launched a series of tools for mold processing since 2008. Among them, GC1010 blade material is introduced for the finishing blade of automobile panel mold. GC1010 blade material is a This is a milling material used for hardened steel roughing to finishing. Due to the combination of thin PVD coating and fine-grained hard matrix, it provides the blade with sufficient toughness and wear resistance at the same time, and also improves the blade line design , Thus providing outstanding processing performance for hardened steel and cast iron. The benefits of GC1010 material are mainly reflected in the following aspects: the outstanding edge line toughness of the blade ensures better resistance to hot cracking and plastic deformation; extends the tool life and ensures the reliability and safety of unattended production ; It can increase the cutting speed of hardened steel and cast iron, thereby improving production efficiency; when wear-resistant PVD materials are required, it is the first choice for finishing automotive panel molds.

Chuck selection

Because the finishing time of automobile cover molds is lengthy, ranging from 10 to 20 hours as short as 30-40 hours as long as more than 30-40 hours, in addition to selecting appropriate blade materials, the selection of clamping methods should not be ignored. This can avoid excessive tool deflection accuracy, resulting in reduced tool life, so it can be used with the CoroGrip high-precision powerful chuck of the Sandvik Coromant tool holder series (Figure 2) to improve machining accuracy. The CoroGrip high-precision powerful chuck has the following advantages: it can improve the surface quality, when the diameter is 3 times, the runout is less than 6μm; it can extend the tool life, according to the rule of thumb, the tool life will be shortened by 50% every time the runout is increased by 10μm; Almost no vibration and low noise level, the runout/balance/torque of each chuck has been proven (the chuck is individually balanced to G2.5). The repeatability is high, the clamping force remains the same after 15,000 cycles; it has outstanding performance in heavy-duty roughing applications, and the exceptionally high clamping force and rigid structure prevent the tool from sliding.

The machining surface quality of automobile panel molds is not only related to the choice of tools, but also to the programmed cutting method. Maintaining the cutting method of down milling is the only way to improve the surface quality. Famen, through the selection of suitable processing tools and optimized CNC programming, the product quality of the mold will be significantly improved, the manufacturing cycle will be shortened, and the manufacturing cost will also benefit directly.