Magnum Venus Plastech Megaject RTM Pro Revison 7_0 User Manual
Page 21
Megaject RTM Pro Manual – Revision 7.00 – 13
th
APRIL 2006
green box, containing an L shows that the sprue is enabled with limit switch
monitoring.
The screen displays the volume of resin injected, elapsed time of injection, actual
pressure in the mould cavity and the current resin flow rate. The resin volume and
elapsed time readings retain there final values from the previous injection, which can
be useful, and are only reset when a new injection is commenced by pressing the
START button.
Figure 3.2 – Manual injection screen, mould control
The mould pressure set point (SP) value is the desired pressure to be maintained in the
mould during the injection. This value is in mbar absolute, and for a typical LRTM
injection, it is suggested that good starting point would be to set this value to
approximately 100mbar below atmospheric pressure (around 910 mbar).
Pump power sets the maximum air pressure available to the air cylinder to drive the
resin and catalyst pumps. This value will vary depending on the type of resin used,
length of pipe to the mould and tooling design etc. It is recommended that a low
percentage is entered initially (<10%) and then modified based upon the response of
the machine.
During the initial phase of the injection, as resin is first introduced into the mould, the
mould pressure will take some time to build. At this time the flow rate will be mainly
determined by the pump power setting. If head pressure clipping is enabled (see
section 4.5), unsmooth operation of the pumps may indicate that the pump power
should be reduced. If head clipping is disabled, care should be taken not to over
pressurise the supply line by increasing the pump power value excessively.
The catalyst ratio can be changed to a value between 0.5% - 4.5%.
To begin the injection, press the START button. The sounder beacon will operate for
a period, to warn the operator that the machine is about to start. The catalyst pump
will then move to the position on the ratio arms specified by the current catalyst
percentage. At this point the head valves change over to the inject position, if enabled
any connected sprues are opened, and then the machine begins to inject.