Helical winding

General considerations same as for helical winding except that carriage motion is not uniform. 

Programmed non-linear carriage motion required. Other machine requirements same as for helical winding. 

Figure 2. Two-dimensional representation of Case 1 dwell calculation. The helical wind angle is A and the band width of the roving is B. ...

Bundle Preparation. Packages of multifileiment yarns are backwound to prepare bundles necessary for the manufacture of a reverse osmosis module. A proprietary winder for this operation has been designed and constructed at Albany International Research Co. This device is capable of helically winding multifilament yarns into bundles around a mandrel. This is done in a manner such that the resulting bundle has uniform cylindrical dimensions and uniform fiber density. This minimizes channeling and optimizes exposure of membrane surface area. 

Figure 7.92 A helical winding pattern. Reprinted, by permission, from P. K. Mallick, Composites Engineering Handbook, p. 184. Copyright 1997 by Marcel Dekker, Inc.

Figure 13.2 Full-scale filament-wound case in helical winding phase (courtesy of Alliant Techsystems Inc.)...

Two a-helices wind around i each other to form a supercoil. 

Figure 3.34. An a -Helical Coiled Coil. The two helices wind around one another to form a superhelix. Such structures are found in many proteins including keratin in hair, quills, claws, and horns.

An arrangement of polypeptide chains in which two helices wind around... 

The primary classes of FW are hoop, polar, and helical. The simplest is hoop or circumferential winding, in which fibers are wound approximately normal to the mandrel axis of rotation with the fiber payout head advancing one band width for each revolution of the spindle. Hoop winding is usually combined with helical winding in more complex parts. Polar or tumble machines are used for parts wound using a planar winding path (such as for a short closed-end pressure vessel). These machines normally have the mandrel mounted vertically, over which a rotating arm wraps fiber onto the mandrel. 

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