Daihen OTC Welbee Inverter W400, Руководство пользователя

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S
ETTING
W
ELDING
C
ONDITIONS
W
ELDING
C
ONDITION
C
HAPTER
6
6-24
The relation between EN ratio setting and welding result are shown in the table below.
EN means the period which the base metal is positive (+) and the torch is negative (-), and EP means the
period which the base metal is negative (-) and the torch is positive (+).
The EN ratio changes about 1% by adjustment amount ‘1’ of the operation. A standard value of the EN
ratio (value at center position ‘0’) and the maximum value and the minimum value of the EN ratio are
different depending on the welding process and each current setting.
TIPS
• The EN ratio is as a guide, and it may become different result according to an actual welding
condition and the working environment.
6.6.8 Adjustment of wave frequency
This section explains how to adjust the wave frequency. In wave pulse welding, cyclically accumulating
two separate unit pulse conditions at low frequency enables to obtain continuous weld bead looking like
rows of fish scales.
Aluminum welding makes a ripple bead using an overlap method.
It can also make welding easier, even if there is a gap between weld parts, because it performs a crystal
miniaturization by vibrating the molten pool, and the welded part becomes more resistant to cracking.
The wave pulse welding changes the wire feeding speed and unit pulse condition.
When it close to the limiting value of response characteristics of wire feed motor, it makes the feeding
amplitude small automatically.
When the wave frequency is 3 Hz or more, the amplitude of feeding speed becomes small. At 5 Hz or
more, it disappears. In this case, the wire feeding speed becomes stable and only the unit pulse condition
changes.
<Image of welding bead form in the wave frequency>
Negative direction EN ratio setting Positive direction
Decreasing EN ratio Increasing
Slow Wire melting speed Quick
Small Gap tolerance Large
*: It is substantially constant penetration.
Wave frequency Image of welding bead form
Low
High
EP
0
EN
len
lep
EN ratio means the current ratio of the EN
polarities (ratio of the areas) at one AC
cycle, and it was shown by percent.
It is defined by the next expression.
EN ratio = x 100%
len
lep + len