Abstract: Conveyer belts (10) are deflected many times along a conveying path of the objects to be conveyed. It has been shown that unpleasant squeaking noises are generated in the region of this deflection between the guide means (12) of the conveyer belt (10) and guide rollers or guide drums. The invention is based on the knowledge that the squeaking noises are caused by the relatively high friction value of the material of the conveyer belt (10). The design according to the invention therefore proposes that at least the outer side of the guide means (12) of the conveyer belt (10) is provided with a coating (26) made from a material with a lower frictional value. As a result, it has been shown that undesirable squeaking noices can be effectively avoided.

Abstract: The invention relates to a core (10) for a spinning bobbin and for receiving a windable material. The core (10) consists of wound strip material (11). Adjacently lying portions of the strip material (11) overlap one another. Production is performed by winding on a winding mandrel (14).

Abstract: Filling material for percolating filters used in the biological treatment of fluids are provided with strips which are made of plastic and are connected to one another via a transversely directed holding web. The strips are arranged one above the other in a plurality of layers in order to increase the strip density. In the filling material according to the invention, the strips are provided with different cross-sections over their length. For example, the strips may be reduced in width in regions adjacent to their connection to the holding web. As a result, the strips can be arranged in one layer with an increased strip density.

Abstract: Contact-filter block (10) for the construction of trickling filters or rotating disc filters such as those used for the biological treatment of waste waters. The tube sections (11) of which the contact-filter block (10) is made up have an outside surface (12) structured in a net-like manner, the outside surfaces of the tube sections (11) being joined by joints (13) to avoid constrictions in the clear cross section of the tube sections (11).

Abstract: Tower packing blocks (10) for biological treatment particularly of waste water, comprising a bundle of tube sections (11) with net-like structured peripheral surfaces. The tube sections (11) are connected together at their end sides (20) by reflector welding. Thus there are formed at the end sides (20) of the tube sections (11) accumulations of material (21) which constrict the free internal cross-section of the tube sections (11). These constrictions render difficult the passage of water to be treated through the tower packing block (10). Thus the effectiveness of such known tower packing blocks (10) is reduced. According to the invention, the accumulations of material (21) at the end sides (20) of the tube sections (11) are of such dimensions, i.e. reduced in width, that they correspond to the cross-sections of the tube sections (11) outwith the accumulations of material (21), and thus the cross-sectional constrictions present in known tower packing blocks (10) are eliminated.

Abstract: Packing material for biological waste water treatment, and process for the production of such packing material. Packing material made of tube-shaped base members with net structured outer surface are provided with at least one water-impermeable surface-increasing element arranged on the outer surface of each base member and directly connected thereto, for increasing the specific growing surface for biofilm.

Abstract: Belts (10) are known which have a main body (11) having a smooth circumferential surface (12) on which a profiling is arranged. According to the invention the profiling is formed by an envelope body (13) surrounding the circumferential surface (12) of the main body (11). The belt (10) can thus transmit heavy driving and conveying forces. The belt (10) is therefore particularly suitable as a driving or conveyor belt.

Abstract: Disclosed is a net (10), especially a spacing net, surface protection net or the like, in which the strands (14, 15, 16) are arranged in three planes (11, 12, 13), and in which the strands (15, 16) of two planes (11, 13) are oriented equidirectionally. As a result, a sufficient thickness of the net (10) can be ensured with a small cross section of the individual strands (14, 15, 16), which keeps the expenditure of material down to a minimum. Because the parallel strands (outer strands 15, 16) of the different outer planes (11, 13) are offset to one another in the direction of the inner strands (14), the intermediate strands (inner strands 14) can be deformed elastically, which results in very good padding properties and thickness variation properties of the net (10).

Abstract: A contact body for a cooling tower in which water to be cooled is distributed from the top of the contact body and in which cooling air flows through the contact body in a cross current and/or counter current flow relative to the water flow, is comprised of a plurality of tubular lattice-type plastic bodies that are assembled to form a packaged element such that respective outer mantle surfaces of the tubular plastic bodies contact one another. The tubular plastic bodies are cut to length from a continuously manufactured endless tube that is formed of crossing stays. The cut length of the tubular plastic bodies corresponds to a selected dimension of the contact body, i.e., the height or width of the contact body. The ends of the tubular plastic bodies on at least one side of the packaged element are connected to one another, preferably by fusing.

Abstract: A plastic contact material is disclosed for the treatment of a liquid, comprising a plurality of strips made of a plastic material and wherein each of the strips has at least one tension element. A process is also disclosed for manufacturing a biological water treatment contact material made of a plurality of strips of a plastics material, which process comprises providing at least one strand at an elevated temperature, and applying the strand to a strip of plastic material while the strand is still at said elevated temperature.

Abstract: A plastic contact material is disclosed for the treatment of a liquid, comprising a plurality of strips made of a plastic material and wherein each of the strips has at least one tension element. A process is also disclosed for manufacturing a biological water treatment contact material made of a plurality of strips of a plastics material, which process comprises providing at least one strand at an elevated temperature, and applying the strand to a strip of plastic material while the strand is still at said elevated temperature.

Abstract: A packing element having a cylindrical outer cover (11) with at least one guiding surface (16, 20, 21) of holohedral construction and dividing the outer cover (11) into several subspaces (19). The outer cover (11) has web ribs (12), running in the longitudinal direction of the cover, and annular ribs (13), running perpendicularly to the web ribs, thus forming approximately square net openings (14).

Abstract: Filling material for percolating filters for the treatment of liquid and process for producing and assembling the material. Especially in biological sewage treatment, filling material must provide the best possible hold for the biological filter film necessary for the purpose and must have uniform wettability. The disadvantage of known apparatuses meeting these requirements is that they either tend to clog or are difficult to produce. The new filling material will work effectively and reliably, while being simple to produce and assemble. To provide ideal growth surfaces for the biological filter film, the filling material has a plurality of plastic strips (20) which are connected to one another by means of a single holding sheet (21). Furthermore, the strips (20) have a special shape, in particular corrugated edges and/or a structured neutral region. The filling material is especially suitable for biological treatment, particularly the denitrification of sewage or drinking water.