Now it's your turn

Why improving productivity in demanding turning operations requires the latest technology

Full order books are the dream of every manufacturing company. But this dream does not get along very well with the shortage of skilled workers that can currently be observed in many places. The Austrian company BHDT is trying to solve this challenging situation by repeatedly testing and implementing the latest technology developments in its own operations. With great success: Thanks to Sandvik Coromant's innovative PrimeTurning™ process, the company has been able to reduce machining time by up to 50 percent, even for materials that are difficult to machine.

BHDT is a family-run company that generates annual sales of 60 million euros with around 215 employees. The specialist for high-pressure systems and components for the chemical and petrochemical industry manufactures at three sites in Austria. In Kapfenberg in Styria, pipes, pipelines, valves and fittings are machined in two shifts on 20 machines for well-known plastics and fertilizer manufacturers. In doing so, the internationally active company relies on its many years of experience and comprehensive know-how as well as on consistently high quality and the latest technology standards. The company has been working closely with Sandvik Coromant for more than 20 years.

"We at BHDT are extremely busy for the next three years. Due to the shortage of skilled workers, which we cannot fully resolve despite our own training program, we have to be highly innovative and actually always a little ahead of the times," explains Production Manager Michael Asinger. Against this backdrop, the company wants to continuously develop and improve itself. In particular, BHDT sees immense potential in the areas of automation and digitalization: "Innovative technologies help us to further optimize our processes and thus successfully master the high workload."

In search of potential for optimization

In the search for further improvement possibilities, the conventional turning processes are also taken into consideration. In order to be able to further increase productivity in this mature area as well, BHDT is interested in a solution with which Sandvik Coromant has set new standards: the PrimeTurning™ process.

"Since its introduction in 2017, the PrimeTurning™ g process has been considered one of the biggest innovations in the field of turning. The special method, which enables turning in all directions, is an extremely productive and efficient alternative to conventional turning," explains Günter Koch, Product Manager Turning Central Europe at Sandvik Coromant. "Unlike conventional longitudinal turning, the PrimeTurning™ method allows the tool to enter the workpiece close to the chuck so that material is removed in the opposite direction. This 'reverse turning' allows for a small entering angle that can achieve significant productivity gains." The concept consists of the PrimeTurning™ process itself, the CoroTurn® Prime Type-A and Type-B tools, the CoroPlus® Tool Path software for PrimeTurning™, and integrations with market leading CAM software.

The testing phase

Now that BHDT have become familiar with the concept, they want to take advantage of the enormous benefits. For this reason, an extensive test phase is started in the plant.

After initial tests on a Traub lathe and a Geminis sliding headstock lathe for machining operations up to 4 meters in length, the final tests will be run on an Okuma Macturn 550 lathe. The second generation of indexable inserts for PrimeTurning™ can already be used here. "A significant advantage of the second tool generation is that the new PrimeTurning™ insert is negative and double-sided. With four cutting edges, it offers twice as many as its predecessor model and thus the possibility of even more cost-efficient machining. In addition, the tool has been equipped with a new, robust insert seat that prevents tool breakage in the event of insert breakage," explains Adnan Alijanovic, Account Manager at Sandvik Coromant.

Tests with the new insert involve machining a variety of material grades, from normal tempered steel with medium strength to stainless materials with normal toughness to extremely tough super duplex materials. The result is significant increases in cutting performance: "Thanks to the PrimeTurning™ process, we can run more than twice the cutting speeds in combination with large feed rates and thus reduce machining time by 30 to 50 percent, depending on the material," reports Christian Eder, Head of Work Preparation at BHDT.

Other advantages include optimized chip breaking without flow chips, which means there are no problems with chip removal. This is an immense gain, considering that otherwise chips easily wrap around the component and subsequently the machine has to be stopped. "Whenever chips have to be laboriously removed with the chip hook, machine utilization is minimized. Moreover, because some of the chips we produce are sharper than a scalpel, we can also significantly reduce the risk of accidents for our machine operators with the safe, stable and continuous PrimeTurning™ process," Christian Eder emphasizes.

Successful implementation

Following the successful test phase, the next step will be to implement the process permanently in the plant. Here, the focus will be on machining processes in which the innovative turning process can fully demonstrate its strengths. Since there is no classic large-scale production at BHDT and many products are only manufactured with short tool engagement times, the focus is on processes in which a lot of material has to be removed. This is because the additional work to be done in terms of setup, clamping and programming, regardless of whether single-part production or small series, is worthwhile due to the corresponding time savings, especially for the extensive roughing operations.

To date, BHDT has used the easy-to-use online tool CoroPlus® Tool Path for programming the special machining process: "We want to implement complete component machining, including roughing, via PrimeTurning™ with the aid of a new programming system in the future for the purpose of further simplification. However, the affordable online solution provided by Sandvik Coromant works perfectly and is a real offer, especially for manufacturing companies that cannot carry out their programming with their own systems," says Christian Eder.

In addition to the machining aspects, there are a number of prerequisites for optimum use of the PrimeTurning™ process, both on the machine and on the component side. For example, the machine should have sufficient power and stability and ideally have a closed design due to the considerable chip flight. The component to be machined and the conditions in terms of tension, overhang, etc. must also be suitable for the new turning process. "We will use PrimeTurning™ wherever it can be used successfully due to component and machine characteristics. We are thinking in particular of roughing and contouring operations, both internal and external machining. In view of the high flexibility that PrimeTurning™ tools bring, they offer us more far-reaching possibilities compared to ISO inserts: Our aim is therefore to use PrimeTurning™ in the future not only for longitudinal and face turning operations, but also to cover grooving and contour turning," explains Michael Asinger.

Strong team performance

At BHDT, everyone involved is convinced of the benefits of the PrimeTurning™ process. In particular, the initial doubts of the already experienced machine operators were quickly dispelled due to the clear machining results: "Everyone saw very quickly that the PrimeTurning™ process offers real added value for BHDT. What is particularly positive for us as a company is that we realized the improvement process collaboratively. After the tests with the experts from Sandvik Coromant, application engineers worked hand in hand with machine operators, the tool store and the plant management to realize the excellent results as a team," Michael Asinger is pleased to report.