Grinding down turbine blade costs

With the help of abrasives manufacturer Tyrolit, the company has met its annual cost-saving targets by improving the process of grinding parts for its gas turbine engines. Working in partnership with the abrasives manufacturer Siemens has introduced a new grinding wheel for the grinding of turbine blades for its small scale (1.5-15MW) industrial gas turbines. The wheels have proved successful as part of a whole process series of improvements.

Targeted to save between 3% and 4% on the grinding process, Siemens engineer Phil Howard set about reviewing the grinding process with the support of Tyrolit application engineer Craig Wafford. After reviewing the process, Mr Wafford suggested some changes to the application including the use of Tyrolit's new Strato Ultra wheel.

Mr Wafford comments: “Tyrolit see grinding as a complete system, so that means we look at the component workpiece, fixturing, machine tool, coolant system and dressing process then adapt them to each other to fully optimise the grinding process. The idea is that Phil and I work together with the operators to make improvements to the individual process components and come up with the strategies that make the process more efficient.”

Tyrolit and Siemens introduced the Strato Ultra wheels and decreased the speed of the wheels on the machines. This has meant a reduction in thermal damage and cracking along with a reduction in time spent profiling and dressing the wheels. Wheel diameter was assessed and table speed and depth of cut were altered. Now only one wheel is used per batch of parts significantly reducing downtime.

Mr Howard explains: “We have managed to achieve a 50-120% increase in the number of parts per wheel and, dependent upon the application, save a great deal of machining time due to fewer wheel changes. This time saving can be quite significant where two or three wheel changes are involved in the production of a batch of components, especially when these wheel changes can take up to 55 minutes including dressing time.

"In total we have managed to save between 5% and 15% in the total production time of the components developed and 10% in processing costs. This basically equates to cost savings of around 25% for the parts manufactured. Our target was between 3% and 4% so this is a great achievement.”

The onsite technical support offered to Siemens by Tyrolit is not the only benefit, as indirect material manager Paul Duncombe comments: “The support we receive from Tyrolit is invaluable. We work well as a team and Craig is onsite for every trial to make sure things go well and everything is working correctly.”

Tyrolit
www.tyrolit.co.uk

Siemens
www.siemens.co.uk