First introduced in 1996, the economical Model KP-6 screw press has gained rapid popularity. The largest markets are plastics recyclers and small dairies and hog farms. Other industries now using the machine include canneries, meat processors, hatcheries, a medical waste disposal OEM, and a range of food processors.

With each production run, value analysis is conducted to add improvements. Already in its twenty-second production release, the machine exhibits a number of significant changes over the original prototype. The principal improvements are (a) the addition of a support bushing so that the screw shaft supported at both ends of the shaft, and (b) the use of a split screen assembly. This "clamshell" screen facilitates 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 requirements.

In conjunction with holding the screw at both ends, it has been necessary to anchor the screen assembly so that it cannot drift into the screw. This is done with positioning rings mounted at each end of the screen assembly.

After poor experience with Sumitomo, SEW Eurodrive, and Radicon hollow shaft gearboxes, Vincent found the Nord gearbox. These come with input bearings rated for 4000 rpm. In addition, Vincent specifies their 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 availability of the rotating cone feature, which is 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; an air cylinder actuator for the discharge door; and a perforated metal screen (in place of 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.