摘要:
Method of producing a high voltage electrical insulation, in that (i) an ultra-violet radiation as well as thermally curable composition, comprising at least one UV-curable and heat-curable epoxy resin, at least one cationic photo-initiator and at least one cationic thermal-initiator, is provided, and that (ii) ultraviolet radiation as well as heat is applied to the curable composition in any desired sequence for a time long enough until complete curing of the curable composition is obtained and products obtained.
摘要:
A curable epoxy resin composition is provided. The composition includes at least one diglycidyl ether of bisphenol A (DGEBA) and at least one diglycidyl ether of bisphenol F (DGEBF) as epoxy resins, in which the weight ratio of DGEBA:DGEBF is within the range of about 15:85 to 45:55; (ii) an anhydride hardener; (iii) and at least one plasticizer. The composition can additionally include a catalyst, at least one filler material and/or further additives. The dynamic complex viscosity value (η*) of the composition is within the range of 0.1 to 20 Pa·s. The present disclosure also provides a process for making the composition and electrical articles including an electrical insulation system made from the composition.
摘要:
A method and associated apparatus for detaching a frozen charge from an inner wall of a grinding pipe of a tube mill such as is used for grinding. The method includes controlling a driving device of the grinding pipe to detach a frozen charge from an inner wall of the grinding pipe, which driving device is operable to apply a driving torque to the grinding pipe. Controlling the driving device includes varying the driving torque applied to the grinding pipe around a predetermined reference level.
摘要:
Curable epoxy resin composition comprising a polyepoxide; an anhydride hardener; a 1-substituted imidazole as catalyst; at least a diol in an amount of from 5 to 50 phr of said polyepoxide; a filler in an amount of from 200 to 600 phr of said polyepoxide and optionally additives. It shows improved crack resistance properties. An improved process for the fabrication of thermoset articles is also disclosed.
摘要:
An electric insulator including an electric insulation and a semiconducting layer forming on an outermost surface of the insulator that faces the environment surrounding the electric insulator. The semiconducting layer includes a polymer matrix. Particles of a material confer a semiconducting character to the layer. The particles are dispersed in the matrix. The particles include nanostructures.
摘要:
An electrical insulating composition that can be used in high voltage applications. The electrically insulating composition includes silicone rubber and has improved hydrophobic stability over other silicone rubbers. The material is particularly suited to be used in high voltage (>1 kV) composite insulators.
摘要:
Method of producing a high voltage electrical insulation, in that (i) an ultra-violet radiation as well as thermally curable composition, comprising at least one UV-curable and heat-curable epoxy resin, at least one cationic photo-initiator and at least one cationic thermal-initiator, is provided, and that (ii) ultraviolet radiation as well as heat is applied to the curable composition in any desired sequence for a time long enough until complete curing of the curable composition is obtained and products obtained.
摘要:
A method and associated apparatus for detaching a frozen charge from an inner wall of a grinding pipe of a tube mill such as is used for grinding. The method includes controlling a driving device of the grinding pipe to detach a frozen charge from an inner wall of the grinding pipe, which driving device is operable to apply a driving torque to the grinding pipe. Controlling the driving device includes varying the driving torque applied to the grinding pipe around a predetermined reference level.
摘要:
The bushing has a conductor and a core surrounding the conductor. The core comprises a sheet-like spacer, wherein the spacer contains filler particles. The bushing can be a resin-impregnated graded bushing impregnated with an electrically insulating matrix material. The spacer may comprise paper, in particular creped paper. The filler particles can be electrically insulating or semiconductive particles. An increased thermal conductivity of the core can be achieved.
摘要:
A supply circuit for a fluorescent tube installation with a high-voltage transformer (T) which is connected, input-end, to a supply voltage with a frequency of several hundred Hz, and which is formed without an air gap. To replace the air gap in the transformer, an electronic regulator (EST) is nonetheless used in the supply circuit, which emulates the current-limiting function of an air gap. The frequency of the supply voltage is between 300 and 800 Hz, preferably 400 Hz. As these frequencies are higher than the usual network frequency of 50/60 Hz, the size and weight of the transformer can be considerably reduced.