A heat exchanger has a hollow fiber membrane layer comprised of a plurality of hollow fiber membrane conduits each of which has a hollow portion allowing a heat medium to pass therethrough. The conduits are derived by winding a base cord of the hollow fiber membrane onto a cylindrical body. The winding follows a generally helical trajectory around the longitudinal axis of the cylindrical body with a plurality of continuous round trips from the first end to the second end and turning back at each respective end, wherein each round trip completes a number of circumferential revolutions N, wherein N is greater than or equal to one, and wherein N is less than two.

The present invention concerns a method and apparatus (14a) for winding a section of each of one or more layers of material (18a) around a mandrel (30) and about a longitudinal axis of the mandrel (30), wherein each layer of material (18a) includes fibers and the winding is performed such that, for the wound section of each layer of material (18a), each of a majority of the fibers is angularly disposed relative to the longitudinal axis of the mandrel (30), and: (1) disposing a tape (82) over the layer(s) of material (18a) such that at least a portion of the tape (82) overlies at least a portion of the wound section of each layer of material (18a) and a long dimension of the portion of the tape (82) is substantially parallel to the longitudinal axis of the mandrel (30); and/or (2) spot-joining adjacent sections of the wound section(s) together.

Method for bonding by wrapping a medium which expands transversely to a winding with an adhesive tape, in which: an adhesive tape is unrolled from an adhesive tape roll, the unrolled adhesive tape is provided on one side of a carrier film (1) with an adhesive cement layer (2) and on an opposite side partially with a separating agent layer (3), wherein the area covered by the separating agent layer (3) takes up not more than 50% of the total area of the carrier reverse side, wherein at least the surface of the side of the carrier film (1) which is furnished with a separating agent layer (3) is etched, the adhesive tape is wound around the medium which expands transversely to a winding, so that at least a portion of the adhesive tape is bonded to a lower winding ply by the adhesive cement layer (2).

A paint roller manufacturing system includes a cover dispenser for continuously dispensing a windable width of paint roller cover fabric, a fabric supporting and advancing device for supporting the fabric and maintaining a width-wise dimension of the paint roller cover fabric as the fabric advances, a fabric coating applicator for applying a coating to the back side of the paint roller cover fabric while the fabric supporting and advancing device maintains the fabric in a width-wise dimension, and a compressing roller positioned downstream of the fabric coating applicator and configured to apply a compressive force on the coating after it has been applied to the back side of the paint roller cover fabric and while the fabric is supported by the fabric supporting and advancing device. In two-strip embodiments, first and second strip dispensers continuously dispense a first and second windable width of strip material. A guide system guides the first and second strip coming from the first and second strip dispensers to be wound about a mandrel and guides the coated paint roller cover fabric from the fabric supporting device to be wound about the first and second strips. An adhesive applicator is configured to apply adhesive on substantially all of the outer side of the first and second windable strips and positioned to apply adhesive to the outer side of the first and second windable strips upstream of a location where the coated paint roller cover fabric is wound about the first and second strips.

Method for bonding by wrapping a medium which expands transversely to a winding with an adhesive tape, in which: an adhesive tape is unrolled from an adhesive tape roll, the unrolled adhesive tape is provided on one side of a carrier film (1) with an adhesive cement layer (2) and on an opposite side partially with a separating agent layer (3), wherein the area covered by the separating agent layer (3) takes up not more than 50% of the total area of the carrier reverse side, wherein at least the surface of the side of the carrier film (1) which is furnished with a separating agent layer (3) is etched, the adhesive tape is wound around the medium which expands transversely to a winding, so that at least a portion of the adhesive tape is bonded to a lower winding ply by the adhesive cement layer (2).

A wind-by-wind printer of three-dimensional envelopes is disclosed. A partial envelope is rotated by a turntable, a printhead is positioned proximate to a pervious fiber wind according to a three-dimensional model of the complete envelope, and unmelted fiber is dispensed and joined to the pervious wind. Several source fibers may be merged into a single build fiber toward printing. The source fiber may be modified toward printing, for example by shaping, painting or heating without melting. Several printing units may concurrently operate for adding several fiber winds to the envelope during a single revolution of the turntable.

A method of manufacturing a spiral-wound PTFE gasket includes winding a laminated PTFE tape (300) around a shaft (305) that has an outer diameter that coincides with the gasket inner diameter to create a PTFE cylinder (315) having an outer diameter that coincides with the gasket outer diameter; sintering the PTFE cylinder (315); and removing a radial segment of the PTFE cylinder (315) to form the gasket (100), the radial segment having a thickness that coincides with the gasket thickness.

A method of manufacturing a spiral-wound PTFE gasket includes winding a laminated PTFE tape (300) around a shaft (305) that has an outer diameter that coincides with the gasket inner diameter to create a PTFE cylinder (315) having an outer diameter that coincides with the gasket outer diameter; sintering the PTFE cylinder (315); and removing a radial segment of the PTFE cylinder (315) to form the gasket (100), the radial segment having a thickness that coincides with the gasket thickness.