Dawson Shanahan, the leading European precision cold forming and engineering company, in partnership with Asahi Diamond Industrial, has perfected a production process for the precision grinding of small component parts, to tolerances of just a few microns, at high speed and in large volumes. Ideally suited to parts manufactured for medical, automotive, electronics and aerospace applications, the process runs on custom built systems supplied by specialist machine builder E-Tech, and produces results that are believed to be far better than anything currently achievable in a commercial environment.

Dawson Shanahan claims that the process is capable of producing parts with exceptionally accurate, highly polished surface finishes, with tolerances of less than 1.0micron when measured over each square millimetre of surface area. Similarly, for components with angled faces, the company quotes levels of deviation that are less than 0.5degrees across surfaces measuring just a few millimetres in size. Machine cycle times are typically around 2.5seconds, with no need for further polishing or de-burring of components, enabling Dawson Shanahan to offer its customers from around the world a 24/7 high volume, cost effective precision grinding service.

There are several critical stages that are key to the success of the new production process: the combined computer control and mechanical stability of the machine systems; the composition and precision of the Asahi grinding wheels; and the quality management procedures followed by Dawson Shanahan.

The E-Tech automated grinding machines use the latest Siemens touch screen PLC controls, linked to automatic balancing and anti-vibration systems for each grinding wheel. The Asahi grinding wheels incorporate precision engineered steel hubs, combined with an advanced abrasive substrate and outer layers of Cubic Boron Nitride and diamond, giving superior chemical and thermal stability, and are automatically dressed on each machine using diamond dressing wheels to maintain an exact profile throughout the operating life of each wheel. The structure of the wheels, combined with advanced cooling systems on each machine ensures that operating temperatures are precisely controlled, to eliminate the effects of differential expansion on tooling and component parts.

Of equal importance to the levels of precision being achieved by Dawson Shanahan are the strict quality control systems employed by the company at its UK factory, with accreditation to ISO 9001 and ISO 13485 GMP. The company has an extensive QC laboratory, using the latest Mitutoyo inspection and analysis technology, and typically carries out hourly tests on each batch of components on, for example, surface flatness, machined depth and angle.

The company’s Commercial Director, Jeff Kiernan, says, “We have invested heavily in the most advanced production and quality systems to create one of the most advanced component grinding facilities in Europe. Through a combination of the latest machine, grinding wheel and inspection technologies we have been able to develop a production process that can consistently achieve sub-micron levels of precision for ground parts, at high speeds and large volumes. As far as we are aware, this is the first time that an engineering company has been able to achieve such a feat on a commercial scale, and our success is a reflection of the skills of our in-house team, and that of our partners Asahi and E-Tech.”