PCD tool in the automobile manufacturing industry
In Europe, according to research published by the European aluminum Association (EAA), the amount of aluminum used in a new car in 1990 was 50kg. By 2005, that number had risen to 132 kilograms. A further 25kg of aluminum is expected to be used in each new car by 2010. According to the study, two million tons of aluminum parts were made in new cars made in Europe in 2005. Using aluminum parts to make cars lighter could save 1 billion liters of fuel a year and reduce carbon dioxide emissions by about 40 million tons over the life of those cars.
In the body of a car, most aluminum parts are concentrated on the air conditioning system, engine cover, shock absorber parts, and steering column. In automobile chassis and suspension assembly, aluminum parts are mainly concentrated on wheel hub, suspension bracket, and steering system assembly parts. In the power transmission system, most aluminum parts are located on the cylinder head, cylinder body, hood, pump, and cooler. In addition, aluminum alloy seals, body shell and chassis applications are also increasing.
Replacing steel with a denser material as a conventional structural material is also important in other industries such as general machinery manufacturing and aviation. However, because the hardness of aluminum alloy is not too high, and has a higher toughness, so its cutting is more difficult. In processing, aluminum alloy is easy to bond with the tool material and appear cold work hardening phenomenon, so in low-speed cutting, the tool's front edge is easy to produce chip tumor.
Dry cutting
Due to sensitivity to environmental impacts, automotive parts are increasingly being cut dry or machined with minimal coolant. The cooling cost savings (including associated waste liquid recovery and treatment costs) are also driving a significant increase in cutting speed that is not possible with conventional cemented carbide tools.
When using a conventional tool or tool material for dry cutting, the surface finish of the workpiece is poor due to the change in the geometry of the cutting edge of the tool and the increase of heat caused by friction in the cutting area.
Higher machine speed
Last but not least, the development of machine tool technology makes its spindle speed and feed constantly improve, so as to achieve faster machining. Only a few years ago, the spindle speed of the machine tool was only 6000r/min, but now it has reached 30,000-40000r /min, and the movement acceleration of the shaft can reach 2G. This machine, supported by powerful computer power, is capable of achieving the movement required for machining (e.g., screw interpolation in thread milling).In order to convert this speed advantage into a machining advantage at the point of action, the corresponding tool material is required. However, with carbide cutting tools, the cutting speed can only reach 400m/min. Tools with polycrystalline diamond (PCD) cutting edges can cut up to 3000m/min(depending on the cutting process).In addition to higher machining speed, the main benefits of PCD tools include longer tool life and (in many cases) better surface machining quality.
JEL precision tools, part of the German Komet group, offer a wide range of PCD tools to the market, including DRILLCUT and DRILLMAX for high-efficiency PCD drills with carbide body. These two drills are capable of drilling holes up to a depth of 5D. The DRILLCUT is a straight groove bit with 2 cutting edges and 4 guide edges and is provided with a coolant channel for internal cooling.DRILLMAX also USES the same internal cooling design, but it is a spiral grooved bit with 2 guide edges.DRILLMAX bit positioning accuracy, drilling accuracy up to it8-it9 and can obtain a long tool life and good surface finish. The company also includes PCD slot cutters in its product line. During machining, the PCD cutting edge of the tool is drilled into the center hole from the upper part of the workpiece and then cut off the center. The maximum cutting depth is up to twice the diameter of the tool. These tools can also be used for suitable milling, as well as for machining circular geometry to achieve the good surface finish and burpless cutting edges. Standard 2-edge PCD cutters have a minimum diameter of 6mm and 3-edge cutters have a diameter of 16-20mm.
High-reliability thread milling
JEL is one of the few technical authorities in the field of complex internal threading, particularly when it comes to thread milling or developing specialized solutions for specific processing. The famous MGF and TO MILL thread mills are the most commonly used machining tools.MGF thread milling cutter with PCD tip has a sunk hole in the shank, and the cutter body is made of hard alloy material, especially suitable for processing aluminum alloy and other materials usually processed by PCD. The tool can mill m6-m12 standard thread sizes with a cutting edge length of 2 times a nominal diameter. Similarly, TO MILL(GWF) thread milling cutters with diameters of 16mm and 20mm can mill threads with diameters ≥20mm.In addition, JEL offers process-oriented solutions that include as many processing operations as possible.PCD tip drills and thread milling cutters (BGF) have also been developed that, in addition to producing screw holes, 90° chamfers and threads, can also produce protective countersunk holes in a single machining operation.
Examples of auto parts processing
One example of the vabos-k modular tool concept (variable drilling, counterboring and thread cutting system) with bit and thread milling cutters is machining spark plug threads on die-cast aluminum. With this tool, the machining of the screw hole, 90° chamfering, spot-facing, face facing with diameter 22mm and M14×1.25 thread can be completed through one processing. All cutting elements of the tool use PCD tips. The values-k modular tool system was developed for processing where the use of indexable blades in tool clips is not possible due to shape, size, or precision requirements. To process 90° chamfering, spot facing, and face facing, the PCD cutting edge is welded directly to the vabos-k head and the head is then fixed to the cutter body or clamp, and the cutter body or clamp can be easily removed to install the new PCD cutting edge. This knife clip is a one-time purchase of accessories. Center drills and thread mills can be easily installed in place without time-consuming adjustments.
Another example of a specialized tool developed by JEL is also a vabos-k tool system. The system consists of a solid carbide bit and thread milling cutter (BGF) for drilling through holes with internal threads, counter facing holes and M6 threads on aluminum shell workpiece. The salient feature of the tool is that it can process countersunk holes with a diameter of 50mm. Only the PCD tip can be used for machining at a steady maximum speed of 10000r/min (equivalent to a cutting speed of 1570m/min at a diameter of 50mm). Only in this way can a very short total processing time (3.9 seconds) be achieved.
The vabos-m tool system for finishing prefabricated holes in fuel filter housings has a PCD Tomill thread mill. The process of machining countersunk hole contour, counter facing hole, outer edge deburring and milling S80×3 sawtooth thread can be completed with one machining operation. Processing time per hole can be reduced to an incredible 8.8 seconds. One of the features of the tool is that the design of the thread milling cutter enables the first thread processed on the workpiece to be a complete thread.
Circular cutting and groove cutting machining
When contour machining is required on the inner and outer diameter of the workpiece (such as grooving in the hole and machining cavity), circular milling and turning can only be realized on the flexible machining center, and circular cutting and grooving is a feasible alternative processing method. This kind of processing will be in the lathe insert the principle of processing upside down and turning the workpiece rotation, tool static way is different, it is the workpiece static, tool movement. The tool is processed by the circular interpolation path generated by the CNC system of the machine tool into the stationary workpiece. In this process, the cutting edge of the tool is perpendicular to the tangent of the cylinder of the hole at each point in the circular interpolation path. The result is that for every turn the tool makes around the workpiece, it only turns around its axis once. The surface machined by circumferential cutting and grooving will not produce the special cutting mark surface of circumferential milling. Such tools with PCD cutting edges are also available for aluminum parts.
German Komet group is composed of the Komet precision tool company, Dihart precision tool company and JEL precision tool company. The group has approximately 1500 employees around the world, engaged in the production and sales of precision cutting tools, its main technical areas are a hole, thread general processing and precision processing, special thread cutting, standard, and special PCD tools and turning tools. Komet is a market leader in mechatronics (tools with built-in NC axis for cutting edge positioning and tools with NC contorting).
