Piston on ring test

These statistical approaches can not be applied directly to the experimental results in this study, because the fracture was occurred under biaxial stress in Disk-on-Rod tests and Piston-on-Ring tests. The statistical approaches for multiaxial stress state have been studied by several investigators. In order to determine the suitable equivalent stress more precisely, further investigation is needed for the widely variable stress states. However, it is considered that uniaxial statistical approach by eqs. (2) (5) are available for the comparison of the critical stress for maincrack formation under... 

Installation for Ultrasonic Testing AKV-S is designed for testing of diesel motors pistons. Particularly, this device identifies the areas with cracks and lowered adhesion on interfacial boundary between niresist ring and base material. 

Figure 45(d) shows the determination of the tensile strength of model agglomerates by means of the wall friction method.For this test a cylindrical pellet—sometimes with a central pin—is produced in a press. After removing the specimen from the press, it is stressed directly in the die shell. The tensile force is transmitted by adhesion between the end surfaces and the pistons as well as on the circumference and the die walls. Again, the tensile strength is defined by the quotient rupture force P divided by the cross section of the cylindrical or ring-shaped sample. 

Association of Phosphorus Emission with Oil Consumption and Volatility—Oil consumption caused by oil volatility has always been a concern for automotive engineers because of the associated deposits often formed on piston rings, combustion chambers, and valves. Concern that oil volatility could cause phosphorus in the exhaust stream adds to the desire to reduce oil volatility. Consequently, progressively lower formulated engine oil volatility (as measured by the classic Noack volatility test [9-12]) was required for oils meeting API and ILSAC GF-2 (22 % loss) and GF-3 (15 % loss) specifications. 

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