Sökning: "silicone"

Visar resultat 21 - 25 av 110 avhandlingar innehållade ordet silicone.

1. 21. Influence of Ageing on Material Properties at Interfaces in Composite Insulators

   Författare :Johan Andersson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite insulators; ageing; silicone rubber; salt fog test; Outdoor insulation; inclined plane test; interfaces;

   Sammanfattning : High quality of internal interfaces in composite insulators for high voltage applications is necessary for securing durability of their functionality. Weak macroscopic interfaces between the glass fibre reinforced (FRP) epoxy core and the silicone rubber (SIR) housing, such as spots with reduced bonding or a loss of the adhesion as well as presence of foreign contaminants, can appear to have an accelerating effect on the evolution of ageing processes, though it may take years before the first signs of processes endangering the insulator function appear. LÄS MER

3. 22. Improved Flame Retardant Properties of a Halogen-Free Material for Cable Applications

   Författare :Linus Karlsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flame Retardant; Melt Viscosity; Silicone Elastomer; Ethylene-Acrylate Copolymer; Calcium Carbonate;

   Sammanfattning : Due to the large amount of electric equipment in our surroundings, fire safety of cable materials is becoming increasingly important. Because of environmental and health issues, much focus is on development of halogen-free materials. In this thesis, a halogen-free flame retardant material named Casico™ is studied. LÄS MER

4. 23. Electrical Charges on Polymeric Insulator Surfaces and their Impact on Flashover Performance

   Författare :Sarath Kumara; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; streamer criterion; polymeric insulation; flashover voltage; surface potential; bulk conductivity; surface conduction; humidity; bulk neutralization; charge decay; Surface charge; silicone rubber; corona charging; gas neutralization;

   Sammanfattning : Utilization of remotely located sustainable energy resources such as solar, wind and hydro calls for further developments of long-distance electric power transmissions operating at ultra-high voltage (UHV) levels which may exceed 1000 kV ac and 800 kV dc utilized today. It is foreseen that insulation of such transmission systems is to be based on polymeric materials that can provide a number of technical benefits over traditionally used glass and porcelain based insulation. LÄS MER

5. 24. Mechanism of a polyolefin based effervescent flame retardant material

   Författare :Anna Lundgren; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; intumescent structure; flame retardant; Casico; silicone elastomer; polyolefin; effervescence; calcium carbonate;

   Sammanfattning : ABSTRACTFire safety issues are becoming increasingly important in modern society and cables are one potential fire risk since they can start and/or spread a fire. As a result of environmental and safety issues having to do with flame retardants based on halogens, much attention has lately been given to finding halogen free alternatives. LÄS MER

7. 25. Effects of Corona and Ozone Exposure on Properties of Polymeric Materials for High Voltage Outdoor Applications

   Författare :Bin Ma; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; surface resistivity; silicone rubber; nanocomposite; Outdoor insulation; ozone treatment; dielectric response; hydrophobicity; corona treatment; composite insulation; volume resistivity; ageing.; mechanical strength;

   Sammanfattning : Despite the past four decades of service experiences with polymeric insulators in power systems all over the world, an adequate standard allowing for proper selection of polymeric materials for applications in high voltage outdoor environments has still been lacking. Therefore CIGRE Working Group D1. LÄS MER