LIBRARY ı6ıul 0) - Cranfield University

Step 5
Step 6
Step 7
Step 8
Step 9
Step 10
Given the stand-off, SO , and the wire feed speed, WFS , calculate the
expected mean current, Imean
, using equation (3.1);
If Imean is greater than the maximum allowable value, then jump to Step 22.
Otherwise estimate the expected side leg length, Legside
, and bottom leg
length, Legbottom
, using equation (3.6) and their average value, Legav
.
If the leg length values comply with the restrictions, then calculate the
expected value of the transfer stability index, TSI, from equation (3.2).
Estimate the mode of metal transfer by comparing the TSI predicted value
with the limits shown in Figure 2.8. If the TSI predicted value is out of the
range in which a stable dip transfer or a stable spray transfer is expected to
occur, then force its value to one of these stable regions, using TSI = 1.25 as
the threshold for switching the mode of metal transfer from dip (TSI _> 1.25)
to spray (TSI < 1.25).
Estimate the value of the transfer index, TI, based on the adjusted value of
TSI, using equation (3.11). This equation results from dividing both sides of
equation (3.3) by Imean
and adjusting the terms as in equation (2.3).
TI =1-
I mm =1- 1 1- a, 1m°ß
I. ß3 1ean
(3.11)
Estimate the value of the dip consistency index, DCI, based on the adjusted
value of TSI, on the value of TI estimated in Step 9 and on the values of Imean
and SO, using equation (3.12). This equation was obtained by substituting
Im,,,
for its corresponding value, obtained from equation (3.11), into equation
(3.4) and applying the latter into equation (2.5)
DCI=1-
Vbk =1-{a4++84SO
V,.
73
(3.12)