Material Performances Analysis and Life Prediction of Cr5Mo Furnace Tubing

Cr5Mo furnace tubes have been investigated by means of macrographic observation, chemical composition analysis, hardness testing, mechanical property analysis and metallographic examination. The results showed that after a long period serve under high temperature, the yield stress of furnace tube had decreased rapidly and pearlite spheroidization getting severer. Based on the results of endurance test under high temperature, isotherm method and L-M extrapolation were adopted to predict the remaining life of furnace tube, assessment showed that the furnace tube was able to serve for another cycle under the operating temperature of 650 ℃ and the stress of 18 MPa.