Skip to Main Content

Abstract

One of 14 vertical radiant tubes (RA 333 alloy) in a heat-treating furnace failed when a hole about 5 x 12.5 cm (2 x 5 in.) corroded completely through the tube wall. The tube measured 183 cm (72 in.) in length and 8.9 cm (3 in.) in OD and had a wall thickness of about 3 mm (0.120 in.). Failure occurred where the tube passed through the refractory hearth (floor) of the furnace. Although the furnace atmosphere was neutral with respect to the work, it had a carburizing potential relative to the radiant tubes. Analysis (visual inspection, 250x spectroscopic examination of specimens etched with mixed acids, metallographic examination, and chemical analysis) supported the conclusions that the premature failure of the tube by perforation at the hearth level resulted from (1) corrosion caused by sulfur contamination from the refractory cement in contact with the tube and (2) severe local overheating at the same location. Recommendations included replacing all tubes using a low sulfur refractory cement in installation and controlling burner positioning and regulation more closely to avoid excessive heat input at the hearth level.

You do not currently have access to this chapter.
Don't already have an account? Register

2019. "Corrosion Failure of a Radiant Tube in a Furnace", ASM Failure Analysis Case Histories: Steelmaking and Thermal Processing Equipment

Download citation file:


Close
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal