MALLARD® Continuous Taper End Caps:  

Improper injection screw design can mechanically degrade polycarbonate / RPVC and foam volatiles.  The result can be the same streaked appearance caused by processing improperly dried PC.  Older end cap designs often have stagnant flow areas and typically do not seal well against the higher pressures required to mold polycarbonate and some other engineering thermoplastics.

Over time, material that stagnates in the flow path or leaks at a parting line then shows up as black or brown steaks or specks in the molded part.  Zeiger Industries improved design features a constant taper flow path, which eliminates the potential for material stagnation.  The one-piece end cap also eliminates melt leakage into the parting line between the pieces, thus avoiding degradation.

 

mallard ® end caps & continuous taper end caps