Category: Machining Concepts

HORN: Processing of Lead Free Alloys

Specially developed geometries provide a high degree of process reliability when machining lead-free materials

The alloying of lead in metallic materials has a positive effect on the machining process. Due to the EU’s REACH and ROHS regulations, the time of these easy-to-machine materials is over in many applications. However, reliable machining must still be possible in the future. With its broad tool portfolio, Paul Horn GmbH has a suitable solution for almost every application.

The main problem when machining lead-free alloys, be it brass or free-cutting steel, is the lack of reliable chip breaking. But what exactly is the effect of the alloy component lead, which is toxic to humans? During machining, the soft metal creates predetermined breaking points in the alloy, as lead forms small nests or inclusions in the alloy structure. These ensure good chip breaking and low cutting forces during machining. Furthermore, the heavy metal acts like a lubricating film, which has a positive effect on tool wear.

The changeover was initially a challenge. The good cutting properties of the lead-alloyed materials were lost. In addition, the wear on the cutting edge increased significantly. This was remedied by grooving and longitudinal turning with chip-breaking geometries from the steel sector and special laser-cut geometries. Extensive investigations show that chip-breaking geometries for steels with medium strength in particular work very well with lead-free materials.

With the new Type 105 Supermini, Horn has developed a universal boring tool with sintered chip form geometry

During internal boring, adapted geometries also ensure reliable chip breaking. One of the biggest challenges in internal machining is long chips. These often occur during bore machining. They wrap around the tool, clog bores or, in the worst case, lead to tool breakage. Previously, specially lasered or ground chip form geometries were used for this purpose. However, this was associated with a corresponding cost factor for the cutting insert. With the new Type 105 Supermini and the Type Mini with I geometry, Horn has succeeded in developing universal boring tools with sintered chip form geometry. The tools offer high process reliability in use thanks to good chip control. The cutting edge geometry extends far into the corner radius of the insert. This ensures chip control even with small infeeds. The geometry can be used universally for different material groups and is suitable for internal, face, copy and reverse turning.

Please contact us for adapting your tooling solution for the machining of lead free alloys to meet the new requirements of the industry.

 

Hommel+Keller: Roller Burnishing Tools

High Process Reliability with Short Turnaround Time

Roller Burnishing Tools from Hommel+Keller Präzisionswerkzeuge GmbH, Germany are the ideal solution for users who require a very smooth and simultaneously hardened surface – in the shortest possible machining time. With roughness depths below Rz < 2.0 μm, roller burnishing tools offer an economical alternative to conventional fine machining methods. Thanks to their compact design, the roller burnishing tools can be used directly in the existing machining center – without special machines and without additional clamping.

 

Features & Benefits :

  • Spring force up to 450 N, spring travel 2 mm
  • Three roller types: R0.4 | R0.6 | R1.0 mm
  • Strengthening of the surface layer -> higher fatigue strength
  • Very low investment, fast amortization

Please contact us for more information on Roller Burning Tools, Knurling Tools and Marking Tools from Hommel+Keller Präzisionswerkzeuge GmbH, Germany.

 

Engis: ElectroMill® Diamond Milling Tool – One Tool, Endless Possibilities

Engis ElectroMill Diamond Finishing Tools
The Engis ElectroMill is designed to produce high quality, flat milled surfaces including interrupted cuts or machining bi-metallic materials

Engis Corporation, an industry leader respected throughout the world for providing high-quality superabrasive finishing systems, showcased the ElectroMill Diamond Milling Tool at the recently held IMTEX 2025 Exhibition, as part of its Electrogrip® superabrasive solutions.

The flat machining of bi‐metal surfaces or milling applications involving an interrupted cut can present daunting challenges to PCD or carbide milling cutters.  The inserts may chip during the milling process, resulting in high machining costs and elevated levels of sub‐standard or rejected parts. The Engis ElectroMill is designed to produce high quality, flat milled surfaces, even if an interrupted cut is present or multiple materials need to be machined simultaneously. It effectively replaces expensive, complex cutters in high volume applications such as high strength alloys, stainless steel, ceramics, cast iron, fiberglass pipe, composites and aluminum.

Features and benefits include high stock removal rates, stress-free cutting action, extended tool life, industry standard adapter mountings and milling cutting dimensions.  Additionally, superabrasives deliver longer tool life than conventional milling technology.

Combined with high pressure coolant, the ElectroMill can machine several materials to an extremely accurate value of flatness with very low tooling costs.  On cast iron, this hybrid tool can achieve flatness of up to 20 µm and surface finishes as smooth as 8 Ra over a single continuous length of 25,000 inches.  In some cases, customers have been able to reduce scrap and reworks significantly; this contributes to increased productivity and an improved bottom line.

ElectroMill has been used successfully in the marine, small engine automotive, off-road, agriculture, aerospace and defense industries, as well as ferrous, non-ferrous and exotic materials.

Please contact us for more information on the new Engis Electromill Diamond Milling Tools.

KNOLL Case Study: Bosch Power Solutions, Homburg

Together with the Energy Management team from Bosch Power Solutions, Homburg, the team from KNOLL Maschinenbau, Bad Saulgau, installed high-pressure pumps with frequency converters in 50 machining centers to improve efficiency and power consumption. The pumps were equipped with frequency converters to supply the machines with cooling lubricant as needed. The energy savings are on average over 50 percent.

  • KNOLL KTS High Pressure Pump with Frequency Converter

 

Environmental protection, CO2 balance and energy efficiency are the top issues of our time, and industry is also concerned with them intensively. At KNOLL Maschinenbau, Bad Saulgau, they are given high priority in many ways: in the office building, in production, but also in the products, solutions and services offered. As a leading provider of pumps, filters and complete coolant systems, the company promotes the use of frequency-controlled high-pressure pumps for supplying coolant to machine tools – not only as initial equipment, but also as retrofits. In order to determine the energy savings that can be achieved during ongoing operation, KNOLL developed the so-called E-PASS around fifteen years ago. This measurement service and the associated conversion are now used by numerous metalworking companies.

Continue reading KNOLL Case Study: Bosch Power Solutions, Homburg

HORN Mastering Processes: Hard Machining

 

Mastering Processes: Hard Machining

Shorter machining times, high surface quality and the saving of grinding operations. These are just three of the advantages that hard machining with a geometrically defined cutting edge can bring to the user. With a high level of know-how in tool technology, Paul Horn GmbH offers numerous tool solutions to economically machine steels harder than 56 HRC. The cutting material CBN has proven itself suitable for grooving operations.

CBN (cubic boron nitride) is the second hardest known material on earth after diamond. Tools made of CBN wear much more slowly than other cutting materials when used appropriately. On  one hand, this makes it possible to achieve higher shape and dimensional accuracy, and on the other hand, hard materials (steel up to 70 HRC) can be machined reliably. There are no different grades of CBN. Differentiation is made by the CBN volume fraction, the fillers, the grain size and the ceramic/metallic binder phase (cobalt/nickel). This results in different CBN substrates. Numerous tool systems from Horn can be equipped with the cutting material CBN. In most cases, these are tools specially adapted to the respective application. However, Horn also offers standard tools equipped with this  very hard cutting material.

Hard machining with CBN cutting materials is usually done dry. This is possible because the cutting material has  high heat resistance and the high temperature within the chip formation zone has a positive effect. An insufficient supply of coolant or interruptions in cutting lead to high, thermally induced stresses in the structure of the insert. This can lead to cracks in the structure and thus possibly destroy the insert. During hard machining, the steel in the shear zone undergoes intense heating and is thus softened. Most of the heat generated in the shear zone is dissipated via the chip and not  transmitted into the workpiece. This means that there is no thermal influence on the insert edge  in the process. While carbide  suffers a massive loss of hardness at around 800 degrees Celsius, the hardness of CBN remains almost unchanged even at up to 1,200 degrees Celsius. Another important aspect is the chemical resistance, especially at the prevailing temperatures.

Numerous Advantages

Hard machining with a geometrically defined cutting edge in combination with CBN  has numerous advantages over grinding . High metal removal rates are possible with this process, which results in shorter machining times. Conventional machines  may be used. This offers the possibility of complete machining of the component. Even complex contours can be easily produced on a lathe. With grinding, on the other hand, the  wheels have to be elaborately profiled. The high surface quality that can be achieved with hard turning also saves on further grinding operations.