scope:

This Technical Information Paper (TIP) covers liquid penetrant testing of new suction roll shells produced for new or replacement equipment. This TIP is intended for centrifugally cast and rolled/welded shells. This procedure is applicable to both stainless steel and bronze shells.

It is recognized that no suction roll shell is perfect and shells can deteriorate under widely different applications and operating conditions. Therefore, the purpose of this TIP is to establish procedures for documenting the surface condition of the suction roll shell, as manufactured, so that the information may be compared with data gathered periodically after the shell is in service.

It is beyond the scope of this TIP to recommend criteria for rejection of new shells based on the size or quantity of flaws. However, manufacturers will usually have standards for acceptance/rejection of shells that they produce. Nevertheless, acceptance criteria should be as agreed upon by the purchaser and supplier.