Abstract: A method for producing an insulated pipe in corrugated casing (100) comprising the steps of: covering an inner pipe assembly (105) comprising at least one inner pipe (101) with a film (106); dispensing an expandable insulation material (102) in a liquid state between the inner pipe assembly (105) and the film (106) thereby preparing an initial pipe assembly (107) comprising a layer of expanding insulation material (102a) positioned between the film (106) and the inner pipe assembly (105); extruding a layer of outer casing (104) onto the initial pipe assembly (105) before the insulation material has expanded completely, thereby creating a still expanding insulated pipe assembly (118); and leading the still expanding insulated pipe assembly (118) through a corrugator (205) having an inner corrugated surface giving the casing (104) a corrugated shape as the at least one layer of expanding insulation material (118) continues to expand.

Abstract: A method for producing an insulated pipe in corrugated casing (100) comprising the steps of: covering an inner pipe assembly (105) comprising at least one inner pipe (101) with a film (106); dispensing an expandable insulation material (102) in a liquid state between the inner pipe assembly (105) and the film (106) thereby preparing an initial pipe assembly (107) comprising a layer of expanding insulation material (102a) positioned between the film (106) and the inner pipe assembly (105); extruding a layer of outer casing (104) onto the initial pipe assembly (105) before the insulation material has expanded completely, thereby creating a still expanding insulated pipe assembly (118); and leading the still expanding insulated pipe assembly (118) through a corrugator (205) having an inner corrugated surface giving the casing (104) a corrugated shape as the at least one layer of expanding insulation material (118) continues to expand.

Abstract: Process for the preparation of a co-initiated polyether polyol, which process comprises the steps of (a) preparing a mixture of at least one aromatic initiator, at least one polyethylene glycol and optionally one or more aliphatic initiators, (b) reacting the mixture obtained in step (a) in the presence of a suitable alkoxylation catalyst with at least one alkylene oxide having three or more carbon atoms per molecule using such quantity of alkylene oxide that the polyether polyol obtained has a hydroxyl value in the range of from 150 to 400 mg KOH/g, and (c) recovering the co-initiated polyether polyol. The co-initiated polyether polyol is very suitable for (the preparation of rigid polyisocyanurate-modified polyurethane foams. Such foams have a good flame retardancy.

Abstract: A process for the preparation of a co-initiated polyether polyol, which process comprises the steps of: (a) preparing a mixture of at least one aromatic initiator, at least one polyethylene glycol and optionally one or more aliphatic initiators, (b) reacting the mixture obtained in step (a) in the presence of a suitable alkoxylation catalyst with at least one alkylene oxide having three or more carbon atoms per molecule using such quantity of alkylene oxide that the polyether polyol obtained has a hydroxyl value in the range of from 150 to 400 mg KOH/g, and (c) recovering the co-initiated polyether polyol. The co-initiated polyether polyol is [very] suitable for the preparation of rigid polyisocyanurate-modified polyurethane foams. Such foams have a good flame retardancy.