Vincent Cone Timers (Vcts); Start Up - VINCENT VP-16 Operation & Maintenance Manual

Vincent Cone Timers (VCTs)

For some applications a timer is used to periodically open the cone. There are two timer
settings on the cone timer. Timer 1 determines the interval between cone openings. Timer 2
determines how long the cone remains open. Both are set by trial and error, manually
opening and closing the cone using the cone positioning valve and then setting the timers
accordingly to make it automatic.
Cone timers are most frequently used when there is no level sensor. With abrasive materials,
low flow to a press maintained under compression will prematurely wear the screw and
screen at the discharge. As an example, we had a location where flow to the press would
stop for hours and the wood waste material would get completely dry, creating a "Presto
Log". When the flow started again, the presto log would not move, blowing out the screens
and bending back screw flights.
Alternatively, the cone timer is used with slippery or slimy press cake that cannot be
dewatered to sufficient firmness to force the cone open.
Cone Timer panels are available from Vincent for a minimal cost.
Check the inlet hopper first. Sometimes debris (or this owner's manual) ends up in the inlet
hopper. Before putting power to the screw press, it is advisable to bump the motor or even
rotate the screw by hand. This will prevent damage to the press in case tramp material has
been left in the press. Also, the screw may have shifted so as to hit the screen. (Minor
rubbing is normal; it will go away once there is material in the press.) To turn the screw by
hand, remove the fan guard on the motor and turn the fan blades. The screw of the press
turns in a counterclockwise direction, when viewed from the drive end of the press.
Check to make sure that compressed air is being supplied to the regulator and that the cone
can be opened and closed. Set the backpressure at a low level and/or start with the cone
open.
1. Start the press. Minor screw-to-screen rubbing is normal and will go away when
material is fed to the press.
2. Begin feeding material to the press. It's helpful to have someone watching the level
in the inlet hopper to ensure that the press isn't overloaded.
3. When material starts appearing at the discharge end, close the cone if it's open.
Increase backpressure on the cone until the moisture level in the press cake appears
to be as dry as you'd like. Continue monitoring the level in the inlet hopper as
increasing backpressure will influence throughput. You may need to increase screw
speed in tandem with increasing backpressure to get desired dryness and adequate
throughput. See the next section on screw speed.

Start Up

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