Page 19 - Workswell Catalogue

Application - Aluminium soldering

CONTINUOUS SURFACE TEMPERATURE MONITORING DURING 18

ALUMINIUM SOLDERING

Soldering is a method of join-
ing parts with molten auxiliary
material, the so-called solder
with the melting point low-
er than the components to
be joined. It is customary to
distinguish the soft and hard
soldering, depending on the
melting point of the solder. Automation
Solders with the melting point
of up to ca. 450 °C are referred
to as soft, above the tempera-
ture, as hard.

Soldering methods may be
distinguished mainly by the
method of heating the sol-
dered parts and solder. In the
larger extent, we heat soldered objects and solder with hot gas flow or flame. Hard soldering ensures greater weld
strength; it is used, for instance, for soldering aluminium or copper pipes.

SETTING OF THE ASSIGNMENT

The company Xxxxx, one of the leading companies in the automotive industry, is involved in the production
of automotive air conditioning and its components. In this case, the temperature course needed to be moni-
tored during aluminium torch soldering to reach the desired temperature and therefore to ensure the proper
soldering operation and a quality joint of the two air conditioning distribution pipes. The second assignment
should ascertain the weld temperature after cooling with water to avoid burning the operator that takes the
component.

SOLUTION OF THE ASSIGNMENT
However, in this particular case, only one thermal imaging camera connected to the ThermoInspector control com-
puter via the Ethernet cable was sufficient. The thermal imaging camera was placed on a static holder to be as
perpendicular as possible to the soldered area, but at the sufficient distance from the flame to prevent damage and
influence the camera’s accuracy by flame.

The system has been configured to the Start/Stop Measurement Mode, which means that the camera monitors the
respective areas in the image (ROI) during the active incoming trigger
signal, the measurement starts on the leading edge and ends on the
trailing edge. The trigger signal was brought to the ThermoInspector
system from the control PLC and it is activated when the flame starts
to solder and deactivated when the soldering is terminated The second
trigger signal comes when the soldered area gets colder with water.

Here only a short signal from the PLC is sufficient. If the temperature
limit on any of the ROI is not met, an alarm is displayed on the screen
that informs the operator and saves the appropriate record to the con-
trol computer for each particular soldering.