What caused the impeder burn?

Recent days, one customer feedback their impeder burn very offen and don't know how to solve, following is our suggestion, and help customer checking and solve problems, if you also have this confuse, try now!

This problem may because two reasons:

First, water cooling not enough, kindly try to apply more water power and cooling at impder section and tube mill place. Second, hf welder welding power adjust not suitable, maybe power too large, and pipe will have more bead once welding, bead scrach the impeder and cause impeder broken. Try to adjust hf welder welding power suitable . or kindly apply your burn impeder photos for us to check.