This paper presents a failure analysis on a failed intake valve in a gasoline engine. During an endurance test, an intake valve was broken and caused some damages on the piston. Material examinations (by a light microscope and also a scanning electron microscope) were conducted on the fracture surface of the intake valve shaft. Results showed that no pores or defects could be observed and the m...

in this paper, the finite element analysis of stability problem of vehicle composite drive shafts subjected to torsional loading is studied. first, using the minimum total potential energy principle, the governing equations are derived and then they are solved by finite element method. the initial geometrical imperfection which is usually in the form of radial displacement, is taken into consid...

Details of 93 roll shaft breakages which have occurred at eight selected sugar mills in Natal since 1979 have been collated and analysed to determine the most likely causes of failure. Theoretical analyses of shaft stresses and fatigue stress concentration factors have been carried out to determine whether present shaft design, machining practices, material specifications and shell assembly tec...

The last phase of the proton transfer cycle of bacteriorhodopsin calls for a passage of a proton from D38 to D96. This reaction utilizes a narrow shaft approximately 10-A long that connects the two carboxylates that cross through a very hydrophobic domain. As the shaft is too narrow to be permanently hydrated, there are two alternatives for the proton propagation into the channel. The proton ma...

Rotating shafts are important and responsible components of many machines, such as power generation plants, aircraft engines, machine tool spindles, etc. A transverse shaft crack can occur due to cyclic loading, creep, stress corrosion, and other mechanisms to which rotating machines are subjected. If not detected early, the developing shaft crack can lead to a serious machine damage resulting ...

In this paper, a modular designed automatic screw tightening shaft system, which is based on enhanced variable gain PID control, is proposed. Designed for the autonomous screw tightening operation, the screw tightening shaft enjoys huge potential for industry application. The screw tightening shaft and the screw tightening process are both mathematically modeled as an uncertain feedback system ...

It is generally accepted that nuclei degrade in developing hair shafts but the point at which such occurs has not been investigated. The fate of mitochondria in the keratinizing hair shaft has been less clear. This study uses transmission electron microscopy to investigate when nuclei and mitochondria are no longer visible in the developing hair shaft. Serial sections were obtained from anagen ...

The aim of this paper is to determine the stress levels at the end of a long slender shaft such as a drilling assembly used in the oil or gas industry using a mathematical model in real-time. The torsional deflection experienced by this type of drilling shaft (about 4 KM length and 20 cm diameter hollow shaft with a thickness of 1 cm) can only be determined using a distributed modeling techniqu...

This paper present a fixture design system of eccentric shaft for ginning machine.. Fixture is required in various industries according to their application. Designer design fixture according to dimension required by industry to fulfill our production tar gate. In traditional manufacturing process performing operation on eccentric shaft is critical. so holding a work piece in proper position du...

The oldest of all the shaft specifications is flex. Once the production problems had been overcome which enabled steel shafts to become a reality, early steel shaft manufacturers began to experiment with producing shafts, which possessed different amounts of resistance to bending. Through the 70 years of shaft design that have followed the introduction of the steel shaft, companies have produce...