Hollow Flight Cooling Screw

General Description

One of the world’s largest producers of polymers and fibers, was looking for a manufacturer that could replicate the existing hollow flight cooling screw processors in their plant. The cooling screw processors are used to reduce the temperature of adipic acid exiting a set of dryers before being conveyed throughout their loading and packaging process. The existing screws were failing prematurely due to fatigue causing expensive downtime and maintenance. KWS designed and manufactured three hollow flight cooling screws exactly to the Customer’s specifications.

Design Parameters

KWS Advantages

KWS engineers were able to use information provided by the Customer and design hollow flight screws that would fit exactly into the existing system without interference. Using the latest 3D modeling software made the engineering work much easier. KWS granted customer representatives unrestricted access to the KWS facilities to exam the screws at various quality hold points throughout the engineering and manufacturing processes. KWS manufactured the screws to meet the requirements of the ASME Boiler and Pressure Vessel Code. Pressure testing the hollow flight screws to a pressure of 225-psi was performed and witnessed at KWS facilities to ensure there would be no leakage issues in the field.

Special Features

The customer was concerned and had experienced premature failure of the center pipe on some of their existing cooling screws. A 2205 duplex stainless steel pipe was utilized to provide higher strength and rigidity to the new screws. The screw flights were manufactured from ASME 304 stainless steel plate to meet the demands of high pressure and corrosion resistance. The bearing area of the shrink fit and seal welded shafts were flame sprayed with a hardening coating for added wear resistance and extended shaft life.