"Tubes Failure"
Question:
"In our Hydrogen Reformer furnace, there was tubes failure on about 22 tubes. During start up (after modification) at about 900 C, some of tube explode & crack. My questions are: What is the cause of failure? Is there any possibility by rate of heating improperly?"
Answer:
It is impossible to tell you how and why the reformer tubes failed without observing/testing them and knowing the operational history. Excessive thermal stresses on startup could cause cracking.