38 research outputs found
Structure and development of pitch canker infected Monterey pine stands at Año Nuevo, California
Entwicklung eines Fertigungsverfahrens zur On-Line Thermoplastimpraegnierung gewickelter Bauteile fuer die Verkehrs- und Energietechnik Abschlussbericht
The objective of this research project was to develop an innovative manufacturing method that allows reinforcing fibres to be on-line impregnated with thermoplastics during wrapping and laid on a liner. The new process is based on the principle of in-situ extrusion of molten polymer on to a conventional fibre strand, which was not impregnated with the polymer, just before the fibres are laid on the liner. The project is divided into three units consisting of eight work steps in total to produce a demonstration component in the form of a fully-wrapped plastic cylinder for service pressures up to 300 bar (burst pressure greater than 900 bar). The concept of on-line impregnation with thermoplastics has been successfully realised using a partially reinforced steel liner. Based on a number of full-scale tests carried out, the good bursting behaviour, fatigue strength and ageing resistance of the component have been demonstrated. A plastic liner has been developed, which is produced by the rotational moulding process and into which the metallic end pieces (openings) are introduced during the moulding process. The plastic liner has been shown to be compatible with and to have a low permeability for the gases such as air and natural gas to be contained in it at high pressure. The plastic liner reinforced with fibres by the wet winding method has attained a burst pressure of 1050 bar on average. Compared to a conventional steel cylinder, its weight is reduced by about 70%. The new winding technique could not be satisfactorily adopted with the plastic liner. It is therefore necessary to try out other thermoplastics or to develop new process steps in order to achieve sufficient temperature stability during winding. (orig.)Available from TIB Hannover: F99B1076 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman