Abstract: A multi-layered pipe comprising a wall having a polyolefin inner layer and a barrier layer being an outer layer relative to the polyolefin inner layer, the barrier layer being formed of a non-metallic barrier material, which barrier material has relative to polyolefin an enhanced resistance to permeation therethrough of hydrocarbon molecules, the pipe further comprising a protective layer being an outer layer relative to the barrier layer, the pipe further comprising a peelable layer between the polyolefin inner layer and the barrier layer, the peelable layer being formable around the polyolefin inner layer by means of extrusion. The protective layer and the barrier layer may together be incorporated in a single layer.

Abstract: A multi-layered pipe comprising a wall having a polyolefin inner layer and a barrier layer being an outer layer relative to the polyolefin inner layer, the barrier layer being formed of a non-metallic barrier material, which barrier material has relative to polyolefin an enhanced resistance to permeation therethrough of hydrocarbon molecules, the pipe further comprising a protective layer being an outer layer relative to the barrier layer, the pipe further comprising a peelable layer between the polyolefin inner layer and the barrier layer, the peelable layer being formable around the polyolefin inner layer by means of extrusion. The protective layer and the barrier layer may together be incorporated in a single layer.

Abstract: A multi-layered pipe having a wall with a protective outer layer which comprises PET, wherein preferably the protective outer layer is the most outer layer of the pipe, wherein preferably at least one of the layers is pigmented, and wherein preferably at least one of the layers is transparent, wherein the pipe further has a barrier layer which has relative to polyolefin an enhanced resistance to permeation therethrough of at least one of: hydrocarbon molecules, oxygen molecules, hydrogen molecules.

Abstract: A multi-layered pipe comprising a wall having a polyolefin inner layer and a barrier layer being an outer layer relative to the polyolefin inner layer, the barrier layer being formed of a non-metallic barrier material, which barrier material has relative to polyolefin an enhanced resistance to permeation therethrough of hydrocarbon molecules, the pipe further comprising a protective layer being an outer layer relative to the barrier layer, the pipe further comprising a peelable layer between the polyolefin inner layer and the barrier layer, the peelable layer being formable around the polyolefin inner layer by means of extrusion. The protective layer and the barrier layer may together be incorporated in a single layer.

Abstract: A voltage conversion circuit for the conversion of an input d.c. voltage into a three-phase a.c. voltage (UR, US, UT) in the mains frequency range having at least one inductor (L1, L2) and having multiple switches (S1, . . . , S9) controlled by a drive circuit (AST) in which a first converter section is provided (S1, D1, L1, S2) to produce positive output voltage portions and a second converter section (S3, L2) is provided to produce negative output voltage portions and the output of the first converter section is connected to the three phase outputs (R, S, T) via one each of first longitudinal phase circuit breakers (S4, S5, S6) and the output of the second converter section via one each of second longitudinal phase circuit breakers (S7, S8, S9).

Abstract: A voltage transformer for the conversion of an input d.c. voltage into a three-phase a.c. voltage (UR, US, UT) in the mains frequency range having at least one inductor (L1, L2) and having multiple switches (S1, . . . , S9) controlled by a drive circuit (AST) in which a first transformer element is provided (S1, D1, L1, S2) to produce positive output voltage portions and a second transformer element (S3, L2) is provided to produce negative output voltage portions and the output of the first transformer element is connected to the three phase outputs (R, S, T) via one each of first longitudinal phase circuit breakers (S4, S5, S6) and the output of the second transformer element via one each of second longitudinal phase circuit breakers (S7, S8, S9).

Abstract: A process for producing room temperature-vulcanizable silicone compositions which comprises mixing, in a first step, crosslinkable diorgano(poly)siloxanes, filler(s) and either catalyst(s) or crosslinking agent(s) and a part or all of the optional additives to be used in a continuusly operating closed mixer, and in a second step, metering the crosslinking agents and/or catalyst(s) not added in the first step and the remainder of the optional additivies to be used into the mixture thus obtained in an oscillating pilgrim-step kneader where the mixture is homogenized and degassed.