March 13, 2002,

Revised November 2010

ISSUE #126

First introduced in 1996, the economical Model KP-6 screw press gained rapid popularity.  Initially the largest markets were plastics recyclers and small dairies and hog farms.  Today, the most popular application is albumen recovery from egg shells.  Other industries now using the machine include canneries, meat processors, medical waste disposal, and a range of food processors.

With each production run, value analysis is conducted to add improvements.  Already in its twenty-ninth production release, the machine exhibits many changes over the original prototype.  The principal improvements are (a) the addition of an outboard pedestal and bushing so that the screw shaft is supported at both ends, (b) gearbox and screen mounting which assure rigid screw/screen alignment, and (c) the use of a split clamshell screen assembly.  This change to the screen facilitated both manufacture and maintenance.

Originally the Series KP presses were designed for “soft squeeze”, high capacity applications.  However, supporting the screw at both ends assures that the screw will not drift into the screen even under high torque applications.  This modification has allowed the optional use of lower speed gearboxes to meet tighter squeezing applications.

After poor experience with Sumitomo, SEW Eurodrive, and Radicon hollow shaft gearboxes, Vincent found the Nord gearbox.  These all come with input bearings rated for 4000 rpm.  In addition, Vincent specifies heavy-duty output shaft bearings.  These, being roller bearings rather than ball bearings, carry extra axial loading.  The best Nord feature has been their simple keyed drive, which allows easy removal of the screw even after years of service.

A major improvement is the rotating cone feature, which is now standard.  This construction offers advantages in about half our applications.

Current KP-6 presses still use the original screen length and inside diameter (6″).  Similarly, the standard screw design is still the “sterile-butterfly” configuration that is characterized by high capacity and minimal jamming.  The flat discharge door has taken a modified cone shape.  The cone actuator mechanism itself now provides axial movement, which is a significant improvement over the original pivoting action.

A number of options are available:  1, 2, and 3 hp drives; screw hardsurfacing and notching; weights, instead of an air cylinder actuator for the discharge door; and a choice of perforated metal screen or slotted wedgewire.   Even a short model, with no screw interruptions or resistor teeth, has found applications.  Versions with long inlet hoppers, used where the press is being fed directly from a belt conveyor, have been sold.  All in all, the press has proven a remarkable success in the market place.