Meler Micron PUR LC, Инструкция по эксплуатации

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MELER GLUING SOLUTIONS
4-38
MELTER OPERATION
By-pass valve regulation
The pumping system using a geared pump provides a constant flow of adhesi-
ve, according to the pump’s rotational speed.
In this type of system, the pressure generated by the pump is the result of the
retentions found on the circuit (the length and diameter of the hose, elbows
in the connectors, the diameters of the nozzle outputs, etc.) and the adhesive
itself (its viscosity).
For safety reasons, this pressure must be discharged when the circuit exceeds
the operating value (normally with a closed circuit and the pump activated),
which makes the use of a discharge valve or a by-pass valve necessary.
This valve may be a manual adjustment valve, using a threaded screw, or
with pneumatic control, using a pressure regulator and a pressure gauge. In
the latter case, the adhesive circuit pressure has a 1:13 ratio to the pressure
displayed on the pressure gauge.ç
DOUBLE PRESSURE SOLENOID VALVE (DP2- Optional)
This solenoid valve has two air-inputs and one air-output.
When the solenoid valve is activated, the pressure to the bypass valve is equal
to the net pressure supplied to the melter. At the moment this device is not
activated, air at a regulated pressure is introduced into the bypass valve.
The valve should not be activated when not applying adhesive in order not to
let the system pressure raise. Thanks to that, we avoid the initial overpressure
once the applicator starts applying.
Manual valve control
To adjust the pressure with this valve model (in an approximate manner),
follow these steps:
1. Screw the spindle in clockwise, as far as possible. In this position, the
maximum pressure is 81,5 kg/cm
2
(8,82 bar).
2. Gradually loosen by turning counterclockwise until reaching the desi-
red pressure. Each millimeter that the spindle sticks out represents a
reduction of approximately 9 kg/cm
2
(8,82 bar).
solenoid valve