Process for producing pipe sleeves from mineral wool

Process for producing pipe sleeves made of mineral wool for insulating pipelines or for reducing the sound level in pipeline systems, comprising:

• a) providing a nonwoven web suitable for winding about a mandrel, the nonwoven web made of mineral wool which is provided with an uncured binder;
• b) winding up the nonwoven web on a winding mandrel of a winder in a manner whereby a leading end of the nonwoven web overlaps a trailing end of the nonwoven web to form a coil about the mandrel;
• c) curing the binder;
• supplying at least one reinforcing layer into the winder before the nonwoven web runs into the winder during the winding up of the nonwoven web to at least partially embed the reinforcing layer within the roll of nonwoven web, thereby providing said at least one reinforcing layer before inclusion of the nonwoven web in the pipe sleeve, and providing said at least one reinforcing layer in such a way that during the winding said reinforcing layer becomes an integral constituent part of the pipe sleeve produced as a result;
• and
• providing an outer sheath reinforcing layer added to a trailing end section of the nonwoven web whereby a leading end of the outer sheath reinforcing layer overlaps the trailing end section of the nonwoven web, after providing the reinforcing layer in such a way that said outer sheath reinforcing layer comes to lie on the outside of the pipe sleeve with the effect of a lamination, as an outer layer, the outer sheath reinforcing layer thereby including the leading end of the outer sheath reinforcing layer wound into and embedded within the coil, arranged around the full circumference, and extending completely circumferentially around the coil.