scope:

The purpose of this Technical Information Paper is to provide technical guidance for nondestructive examination of suction roll shells. Although this document is intended primarily for use with shells that have been in service, it is also applicable to new shells. TAPPI TIP 0402-11 describes liquid dye penetrant examination techniques for new shells (1). TIP 0402-17 (2) describes procedures for documentation of weld repairs which are sometimes performed during manufacture of suction rolls.

Timely discovery of cracking, corrosion or other forms of distress is important for avoiding suction roll failures in service. This TIP discusses various nondestructive examination techniques and provides general guidelines for examination frequency. In addition, types of indications that are typically found in suction rolls, and procedures for documenting shell condition are described. This document does not provide guidelines for determining suitability for service or the remaining useful life of a particular shell.