Akzo N.v.

Elmar Hoff

Erich Schurmann

Hermann Gemeinhardt

Ulrich Baurmeister

Werner Sticksel

In a process for fabricating an injection-molded tube sheet of thermoplastic material, for use in an apparatus for transferring heat and/or mass, with at least 25 through-holes for taking up tube ends, a melt is first distributed in the injection mold over the entire cross-sectional area before being pressed into the region of the mold where the tube sheet proper is formed. The injection mold has a needle disposed therein for each hole of the tube sheet being fabricated. After cooling, the portion of the thermoplastic melt without through holes, that is that overlaying the needles, is removed to produce the tube sheet.

Process for producing a tube sheet

In an injection-molded tube sheet of thermoplastic material for apparatus for transferring heat and/or mass with at least 25 through-holes for taking up tube ends, the holes have a hydraulic diameter of at most 3 mm and the minimum web width between neighboring holes is at most 0.4 mm. The thickness of the tube sheet ranges from 3 to 10 mm. Such a tube sheet is particularly suitable for the compact arrangement of tube ends and is therefore used for producing apparatus for transferring heat and/or mass. It is fabricated by an injection-molding process in which the melt is first distributed in the injection mold over the cross-sectional area before being pressed into the region of the tube sheet proper.

Tube sheet for apparatus for transferring heat and/or mass, use thereof

An apparatus for effecting mass and/or heat transfer, comprising a bundle of hollow filaments of substantially equal length, the ends of which are embedded in a sealing compound, a substantially cylindrical housing with connecting branches for the supply and removal of at least two media, the first medium being guided through the hollow filaments and the second medium being guided radially inwardly at the flow inlet of the housing and radially outwardly at the flow outlet, the housing comprising a substantially tubular body and two caps. The connecting branches are disposed in the caps. Each cap forms with the ends of the substantially tubular body two distributor chambers, the first of which is disposed on the end face and the second on the outside jacket of the tubular body. The outside jacket of the tubular body has at least one port in the area of the second distributor chamber. The interior of the substantially tubular body may widen conically from one end area to the other. Preferably, the substantially tubular body has substantially the same linear-change characteristics as the bundle of hollow filaments. The mass-transfer units can be suitably used as dialyzers, in which case the caps can remain fixed in a dialysis system. Methods suitable for manufacturing the apparatus for effecting mass and/or heat transfer are also disclosed.

Growing community of inventors

Bochum, Germany

Elmar Hoff