Screw tips

Posi-Trol screw tips use three-piece construction with a body and spherical retainer that are standard for most valve sizes?only the conical seat is customized to the specific OEM design. The design of the screw tip addresses the common problem of front seat wear in which the ring wears into the retainer, affecting performance and the life of the valve. The screw tips reportedly solve the problem with geometry and design, rather than metallurgy, which translates into cost savings for the user. With quick, consistent shut-offs, the screw tips reportedly offer distinct advantages over other three- and four-piece valves. Generous flow paths and the lack of dead spots allow easy flow of resins and permit simple clean up when changing resin colors. During screw recovery, the resin travels an extremely short distance through the valve, resulting in low pressure drop and low shear. The low pressure drop during the screw recovery phase parallels a lower pressure gradient during the screw forward phase, ensuring positive, quick shutoffs and material savings. The design is reportedly suited to a variety of resin viscosities and applications.

IMS, Chagrin Falls, OH; (440) 543-1615 www.imscompany.com