Search Results

PM parts, similar to those made by other metalworking processes, are not always defect free. Typical defects like cracks or larger pores are usually checked by cumbersome, visual methods with limited effectiveness. Conversely, physical effects can also be used to detect defects through the application of eddy currents, x-ray, optical methods or the measurement of resonance modes. These methods are gaining a wide field of applications in PM today. Some methods investigate the components locally for pre-defined defects, e.g., optical, ultra-sonic or some commonly used sonic inspection systems. Other localizing methods investigate whole components, detecting locations of defects. Sophisticated integral methods allow for the inspection of the whole component. The key point is the signal evaluation. Simple analysis only allows the determination of local defects, i.e., known defects.

In the field of oil pumps for the automotive industry, the volumetric, mechanical, and therefore the total increase of efficiency is the driving force for all advanced development activities. Advanced oil pump systems are developed based on innovations related to design and application of the newest modeling and simulation tools, followed by testing for verification. Several refinements could be achieved by applying the following tactics: design improvements of oil pump gears, the application of alternative forming processes to improve precision and performance (e.g. size rolling instead of standard sizing), the introduction of complete new pump concepts (planetary pump) and the development of new materials with adapted coefficient of thermal expansion to maintain a better axial clearance and higher volumetric efficiency. This paper gives an overview about the state of the art and the new concepts of PM pump technologies.

A new sophisticated self sealing G-rotor type pump with an extraordinary performance was developed by GKN Sinter Metals. This GKN-Planetary-ROTOR allows an efficiency in the typical range of piston pumps. It may be used in typical engines and transmissions as well as in a variety of other applications with a demand of high pressures or high efficiencies at low rpm. The new GKN-Planetary-ROTOR causes much lower production cost than conventional systems with similar performance.