Focus on the biggest source of machine tool processing costs

One of the most detrimental misconceptions that affects the efficient use of tools such as diamond knives is that the price of the tool is equal to the cost of the tool. Jim Graham, processing product manager at Diamond Innovations, called it a "sticker shock" misunderstanding. For example, a machining shop compares the price of an efficient CBN tool with the price of a universal carbide insert. When you see a large difference in price, you may think that a highly efficient tool is less economical. If so?

In fact, efficient tooling may or may not be the right choice, but the price of the tool should be a small factor in making a purchase decision. Although the price of the tool is really included in the processing cost, the tool cost is also subtracted from the processing cost by achieving cost savings in all aspects.

The source of cost for machining a typical part

In order to more clearly illustrate this point of view, it can be considered that the processing plant does not provide the tool to its customers, but supplies the workpiece. Therefore, the cost of the workpiece should be the focus of attention. Moreover, the tool price only accounts for a very small proportion of the cost of the workpiece. Therefore, using an efficient tool to reduce the total cost of the workpiece is actually not difficult.

Among them, the tool cost only accounts for 3% of the total cost of the parts. In contrast, the proportion of labor costs and machine equipment costs is much larger (about 30% each). The table on the right translates these ratios into U.S. dollars for easy calculation. In fact, reducing the tool price has no obvious effect on saving processing costs. Do you prefer to reduce the tool price by 30% or increase the cutting speed by 20%? The analysis of the attached table shows that assuming a reference processing cost of $10 for each part, a 30% reduction in tool price can only save 9 cents. In contrast, a 20% increase in cutting speed can save 45 cents, and its cost savings are 16 times that of tool cuts. The assumption is that in order to achieve a 20% increase in cutting speed, tooling costs will be needed. Increase by 50%.

Now, you can also try to double or triple the tool price from the benchmark cost, and then perform the same analytical calculations. It is easy to see that even if the increase in the cost of the tool is large, it will not affect the savings achieved by improving the processing efficiency. In other words, by applying high-efficiency tooling (even if tooling costs increase), cutting speed is increased, and more workpieces are machined per unit time (hourly or shift), labor costs and machine equipment costs can be reduced. The impact on the total cost of parts minimizes the cost per part of the process.

In addition, some processing plants can achieve higher levels of savings than shown in the attached table by applying efficient tools. Efficient cutting tools that provide long life and high reliability make it possible for processing shops to successfully achieve unattended "light-out" processing even if they have never before used this type of processing. If the shop can automatically process unmanned workers after they leave work, it will be able to make full use of the previously wasted machine tool processing capacity, because the process does not require operator care, and machine tool equipment costs have been paid by the day shift processing, so this The labor costs and machine equipment costs for the processing methods are almost zero. This is where unattended machining can become the most profitable machining method, and only by using efficient tools can this change in machining method be possible.