STP1250

    Fatigue Cracking of a Welded Roll Used in a Paper-Mill Roll Press

    Published: Jan 1994


      Format Pages Price  
    PDF Version (392K) 9 $25   ADD TO CART
    Complete Source PDF (5.7M) 9 $69   ADD TO CART


    Abstract

    A 1-m fatigue crack was found after approximately four months of service in a welded steel roll that had an intended life of 20 years. The roll was part of a roll press used in a paper mill. The fatigue crack originated in a surface discontinuity and propagated parallel to the girth weld. Metallographic examination revealed the discontinuity to have been produced by entrapped welding slag. The discontinuity was 5.5-mm deep by 41-mm long and was small with respect to the overall size of the roll (8.6-m long, 1.5-m in diameter, with a 110-mm wall thickness). Furthermore, the nominal bending stresses in the part were found to be far below the endurance limit of the material. A fatigue crack propagation study, based on Paris law fatigue crack growth, was performed to determine if the stress level in the roll was sufficient to propagate the fatigue crack from the initial flaw size in the transpired time. Further studies were performed to investigate the effect of different flaw sizes and loading conditions on the life of the roll.

    Keywords:

    fatigue, weld, defect, slag, paper mill, roll


    Author Information:

    Zapata, JE
    Senior mechanical engineer and company president, Anderson & Associates, Inc., Houston, TX

    Anderson, SC
    Senior mechanical engineer and company president, Anderson & Associates, Inc., Houston, TX


    Paper ID: STP13986S

    Committee/Subcommittee: E08.01

    DOI: 10.1520/STP13986S


    CrossRef ASTM International is a member of CrossRef.