Welding Inspection & Metallurgy API ICP Self Study Notes

An appropriate flow rate should be maintained to minimize the possibility of
burn-through or combustion. The minimum flow rate is 1.3 ft/sec. (0.4 m/sec.)
for liquid and gas. For liquids, the maximum flow rate usually required to
minimize risk of high hardness weld zone due to fast cooling rate. The
allowable maximum flow rate depends on the process temperature. In general,
4.0 ft/sec. (1.2 m/sec.) is the upper limit. There is no restriction on maximum
velocity for gas lines, subject to maintaining preheat temperatures.
Case Study:
Is it 36” or greater and below the liquid/vapor line?
If it is not 36” or greater, is it in continuous flows?
Is there an ingress of oxygen?
What is the medium?
What is the flow rate?
Is the flow rate 1.3 ft/sec ~ 4 ft/sec
Is preheating to 70°F requires?