the 05/14/2008

Machining solutions given for power transmission equipment

Continual improvements are important instruments for achieving higher competitiveness in the automotive industry. With the

automotive industry being so dependent upon its manufacturing performance, adopting new tooling developments is vital. There

are many examples that prove the benefits of this approach. The automotive industry is focused on cost reduction and it has

every reason for pursuing this vital direction. Cost per Component Today there is a growing focus on the cost per component

along with a more collaborative approach with suppliers on a long term basis to find the ideal tooling solution for component

solutions. Auto manufacturers are looking increasingly to work with competent suppliers of cutting tools and manufacturing

equipment to achieve optimal processes on components. In the world of machining components, how does this work? Here are some

examples where Sandvik Coromant, the global market leader in cutting tools, contributed to increasing productivity. When

turning transmission components in soft stage (Green turning), the indexable inserts with the Wiper technology persuaded

engineers at a German manufacturer that there was considerable room for optimisation in an application they thought of as

optimal. Initial improvements due to this cutting tool development provided the grounds for the machine shop to proceed with

implementing the Wiper inserts on a wider scale. To start with, it was the machining of axle flanges that was improved. The

flanges were machined on a double-spindle machine and production engineers wanted to arrive at the best combination of

productivity and quality consistency. The Wiper insert provided just that. By allowing the feed rate in machining to be

raised from 0.18 to 0.4 mm/rev combined with a surface finish improvement of RZ 16 to 8 microns the production time was

reduced by 30%. By also applying the right finishing grade for steel, GC4005, the tool-life was also lengthened. The machine

shop manufactures well over eight-hundred thousand components annually and the improvements gained through the application of

more modern turning tools have had a considerable impact on the total production costs of the components. This, in the area

of green turning, which is generally thought of in the automotive industry as well exploited with regards to productivity.

Wiper improved turning potential Another example of where the Wiper inserts dramatically improved turning was at a US

manufacturer. Changes to operations involved in the machining of gear components included optimising operations with Wiper

inserts as well as increasing cutting speeds with new inserts. Low-carbon steel forging gear blanks are demanding to machine

because of the softness and smearing tendencies of the material. Poor chip control and built-up edges are typical factors

that limit performance and the machine shop was having production problems due to poor machining. As part of collaboration

with Sandvik Coromant as a qualified tool supplier, a productivity improvement team worked with the engineers at the customer

to improve performance and reduce component scrap. Tests in the low-carbon steel showed that the Wiper geometry WM in

combination with GC2015, normally a stainless steel insert grade, proved to be the ideal insert for the application. By

increasing the feed rate, without deteriorating the surface finish, the effect on production of the parts was a shorter

machining time enabling the same machines to make more components per shift. With the proposed improvements, programmers were

able to increase cutting speed by 20%, to reduce machining time. Tool-life increased from 350 to 600 components per cutting

edge and chip control was improved. Altogether, this contributed to 25% improvement in productivity. Future trends and

special needs Continuous improvements are a vital part of competitiveness in the automotive industry. With growing

flexibility there is also more room to take advantage of cutting tool developments and to let these have more impact on

productivity, process security and quality consistency. Maintaining good practice with leading edge technology is becoming a

critical ingredient for manufacturers within the auto industry to compete globally. The machining of compact graphite iron

and bi-metals are two examples of emerging material areas, which require cutting tool solutions which will provide the

performance and quality results sought by the industry. The complexity of efficiently machining castings like Bi-metal

machining in engine blocks, where aluminium and cast-iron is machined simultaneously, with a reliable production process

needs in-depth R&D and resources. Indexable insert geometry and grade is still very much a technology with potentials for

providing important user benefits.