Smootharc 180 Multiprocess, Руководство по эксплуатации

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15 BOC Smootharc 180 Multiprocess operating manual
More detailed selection charts, including recommendations for welding
parameters (voltage, amperage, electrical stickout, travelspeed and
gasflow rate) can be found in the following pages.
2.6 4T/2T Trigger Latch Selection
On all MIG machines there is no current or wire feed until the trigger
on the torch is depressed. If a welder is doing a lot of welding then he
has to hold the trigger down for long periods of time and may cause
discomfort. This is can be similar to repetitive strain injury (RSI) that has
become a very popular topic for compensation by office workers.
On all machines a special function called 2T and 4T is available. Also
referred to as trigger latching, this special feature allows the operator to
relax the trigger after first depressing it, the gas shielding to start before
the welding commences. This feature is of particular importance as it
ensures that the weld will have adequate gas shielding to eliminate the
risk of oxidisation (contaminants) causing a defective weld. (Remember,
a defective weld may not be detected by a visual inspection.)
The 2T/4T function also allows for the shielding gas to continue after the
weld has finished and cooled. This eliminates the risk of oxidation while
the weld is still in its molten state. This is particularly important when
welding stainless steel materials.