Parweld XTI-303 AC/DC, Инструкция по эксплуатации

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the occurrence in this zone of under-bead cracks.
Hardened zone and under-bead cracks in the weld
area may be reduced by using the correct electrodes,
preheating, using higher current settings, using larger
electrodes sizes, short runs for larger electrode
deposits or tempering in a furnace.
Manganese steels
The effect on manganese steel of slow cooling from
high temperatures is enbrittlement. For this reason it
is absolutely essential to keep manganese steel cool
during welding by quenching after each weld or skip
welding to distribute the heat.
Cast iron
Most types of cast iron, except white iron, are
weldable. White iron, because of its extreme
brittleness, generally cracks when attempts are made
to weld it. Trouble may also be experienced when
welding white-heart malleable, due to the porosity
caused by gas held in this type of iron.
Copper and alloys
The most important factor is the high rate of heat
conductivity of copper, making preheating of heavy
sections necessary to give proper fusion of weld and
base metal.
Types of electrodes
Arc welding electrodes are classified into a number
of groups depending on their applications. There are
a great number of electrodes used for specialized
industrial purposes which are not of particular interest
for everyday general work. These include some low
hydrogen types for high tensile steel, cellulose types
for welding large diameter pipes, etc. The range of
electrodes dealt with in this publication will cover the
vast majority of applications likely to be encountered;
are all easy to use and all will work on even the most
basic of welding machines.
Metals being joined & electrode comments
Mild steel
6013 ideal electrodes for all general purpose work.
Features include outstanding operator appeal, easy
arc starting and low spatter.
Mild steel
5.5 Torch installation
MMA cable connections
Connect electrode lead to positive terminal
TIG welding cable connection
Connect the TIG torch to the - terminal and the gas
hose the gas outlet connection. If using a water cooled
torch, connect the water supply hose to the water
connection on the front of the machine. The trigger
control should be connected to the front panel socket.
5.6 Work return lead connection
MMA cable connections
Connect work lead to negative terminal
TIG welding
Connect the work return lead to the + terminal
6.0 Operation
WARNING
When using an open arc process, it is necessary to
use correct eye, head, and body protection.
6.1 MMA Welding Guide
Effects of MMA welding various materials
High tensile and alloy steels
The two most prominent effects of welding these
steels are the formation of a hardened zone in the
weld area, and, if suitable precautions are not taken,
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