DESCRIPTION OF THE MACHINE AND ITS FUNCTIONS
5.2.3 DEGAS FUNCTION (VGP60N)
With the DEGAS function, the vacuum in subsequent
phases will be obtained so as to allow partial ventilation
and avoid accidental leakage of the product from the tank.
It is possible to obtain three subsequent phases of vacuum,
at three different programmable levels; each level is in turn
programmable. At the end of the sequence, the machine
will reach maximum vacuum according to the main VAC
programmed parameter.
In the chart below, we highlight the phases in the event
that F1 was set to 90% for 4 seconds and F2 to 98% for 2
seconds, leaving F3 inactive:
5.2.4 SEAL FUNCTION (SEALING)
After creation of the vacuum and gas flushing, the machine carries out sealing of film on the trays by means of a sealing
A
B
plate
operated by two pistons
provided at the top of the machine (Fig. 1). The sealing time is set using the key
and ranges from 0 to 6 seconds depending on the type of materials used for the film and trays, as well as the plate tem-
perature. The sealing temperature is adjusted by means of the digital thermostat and is normally between 140 and 180°C.
For the exact value to be set, consult the film roll and trays supplier and/or manufacturer, since the parameter is influenced
by several factors (material, film thickness). For the sake of information, if trays are used with 85 micron thick film made
of PP (polipropylene), the temperature set point is approx. 170°C.
B
In any case, the sealing must be uniform; detachment of the film
is normally caused by very low sealing temperatures, while cuts
and haloes on the film surface are almost always caused by an
excessively high temperature.
A
Fig. 1
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Rev. 08 - 04/2017 - Cod. 1500160 - Instruction manual VGP25N / VGP60N