DRILLING TOOLS ARE AN IMPORTANT ELEMENT OF MODERN MINING
Drilling tools that break up the rock and render it in chunks, when, for example, blast hole drillings, bores for pipelines or new shafts in mines are created, are a fundamental part of the process. For the various applications, rotary bits are often used for larger diameters. These usually consist of three movable rollers, which press against the rock when they turn. In this way, the rock particles are gradually broken off. The use of drill bits has also already proven itself in the mining industry, especially when drilling smaller diameters. In combination with the corresponding tool holder and the machine, they work on the same principle as a hammer drill. What both types of tools (rotary bits and drill bits) have in common is that their tool bodies, made of steel (cold work steel, alloyed tempering steel or special steel) are fitted with bit inserts made of carbide in order to break even very hard rock. Because the bit inserts are literally at the forefront when it comes to creating the different cavities in the various types of rock and soil.
MACHINING BIT INSERT SEATS WITH μm ACCURACY
In order to guarantee process reliability in mining, we place great importance on the high-precision production of the tools. For this reason, the seats for the bit inserts are machined to μm accuracy by the drilling tool manufacturers for the mining industry. MAPAL has developed the Rockbit-Drill in solid carbide especially for this application. In combination with the MAPAL hydraulic chuck, customers are able to machine the seats for the bit inserts with high precision.
SUCCESSFUL APPLICATION IN PRACTICE
One MAPAL customer is successfully using the new Rockbit-Drill with a diameter of 16 mm for their drill bits. The manufacturer produces the drill bits from low-alloy steel on a machining centre with a hollow shank taper A63 spindle. The drilling depth is 1xD-1.5xD. The Rockbit-Drill can reliably machine 1,618 bores. The customer is impressed: “We were only able to machine 600 bores with the tool we used to use that was produced by a competitor”. The customer was able to double the feed rate compared to the previous tool they used. And in this way, they were able to significantly increase the number of cycles. Furthermore, the MAPAL tool produces an optimum surface quality of Ra (average roughness value) = 0.8 μm. The Rockbit-Drill has left the customer impressed at every stage of production – both in terms of the accuracy of the bores and the low burr formation.
MASSIVE SAVINGS, MORE PROCESS RELIABILITY AND A HIGHER DEGREE OF AUTOMATION
The customer has also mentioned another advantage they’re able to achieve thanks to the MAPAL tool. Because: Depending on the bore diameter achieved, different bit inserts are pressed into the tool body. The mining tool manufacturer has various diameters of bit inserts in stock for this. The greater the fluctuations in the bore diameter, the more different inserts they have to keep in stock. “Thanks to the high dimensional accuracy you get with the MAPAL Rockbit-Drill, we can significantly limit this variety of bit inserts and therefore save costs. The bores move within a much narrower tolerance field”, the customer is pleased to report. Process reliability also increases. And: “This allows us to achieve a higher degree of automation”.
and business associates,
Who would have thought that about one year after the EMO in Hanover, which I thought went extremely well, we would find ourselves in a situation like the one we’re in today. Under normal circumstances, we would have been meeting at the AMB trade fair in Stuttgart. The industry’s leading trade fairs in September each year were an integral part of the calendar. That was until 2020 came along. Having a trade fair on the scale of AMB is simply unthinkable at the moment. Nobody knows just how long these so-called unprecedented times will last. Here at MAPAL, we’ve tried to use this extraordinary time to our advantage. Not just to take a look within and to examine and optimise internal processes, but also to think outside the box. In times like these, it’s even more important to provide a broad foundation for a company. It’s important to make the future as independent of individual sectors as possible. We decided to focus our attention on answering the following questions, among others: What applications, which were previously only niches for us, still give us the scope for upward potential? In which sectors, which MAPAL has only partially supplied up to now, can we create further added value for customers with our developments? During the process, we came up with a lot of potential for our tools as well as exciting topics and projects. In this issue of Impulse, we present the first success stories from sectors that are new to MAPAL, such as mining or e-bike manufacturing.
I sincerely hope for all of us that we will gradually return to the normality we all know and miss. Until then, stay safe and keep positive.
Dr Jochen Kress