FläktGroup Multi-DENCO, Руководство по эксплуатации

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Medium Connections Multi -DENCO
58 FläktGroup DC-2013-0101-GB • Subject to modifications • R4-05/2018
It is necessary to create a positive pressure inside the pipe. Before applying heat to
pipes, remove Schraeder valve cores and open any other valves, solenoids etc. which
will cause a build-up of pressure in the line and, therefore, blowholes in the joint. Also,
any valve seats, gaskets, capillaries etc. that may be damaged by heat, flux or dry
nitrogen must be removed or protected, (e.g. wrap in a cold damp cloth.).
When making soldered or brazed joints, it is essential that the surfaces to be joined are
clean. Unclean metals do not take the flux properly, which results in bare spots over
the brazing alloy and will not flow. Thin films of soldering alloy make the strongest
joints. Clearances of between 0.02 mm to 0.07 mm are all that are required. Too much
clearance prevents the proper capillary action, wastes alloy, promotes a weak joint and
allows ingress of soldering material in the lines. After completion of joints ensure that
all surplus flux is thoroughly cleaned off. Flux left on the pipes looks unsightly and can
cause oxidisation, pitting and prematurely age the tubing.
6.2.9 Oil traps
Fig. 6-4: Requirements of discharge lines on Multi-DENCO units