Coatings and Linings

Conference Paper - This paper describes the requirements of the standard, additional inspection points, and several uses of the standard in the field where clear specification language was imperative to successful project completion. NACE 5/SSPC-SP 12 standard confined to water jetting - which makes use of ultra-high pressure water that is nonabrasive.  Four levels of visible post-cleaning condition and three levels of non-visible condition are defined.

Hot dip galvanizing steel articles after fabrication is one of the most widely used methods to provide corrosion protection. As a final step in the process, the hot dip galvanized coating is inspected for compliance with specifications. Correct measurement techniques and accurate interpretation of the results are necessary to provide an acceptable hot dip galvanized coating.

Alternatives to cadmium plating on fasteners have been evaluated for a number of years. Torque-tension and corrosion resistance characteristics have been the major concerns. Zinc plating has been a popular substitute, but torque-tension at proper preloads on Grade 8 fasteners requires more torque.  Torque-tension tests were ALSO evaluated on Grade 5 fasteners - same coatings.

A cyclic salt-fog test was used to characterize the corrosion control of various aluminum foil coatings on rusted steel. In the maintenance of minimally prepared steel in a marine atmosphere, a properly designed coating system, containing an aluminum foil layer, would be expected to be significantly more durable than a traditional liquid applied coating.

In ship's ballast tanks, most of coating failures (and corrosion attacks) were observed on sharp steel edges, welds seams and weld spatters. One solution is to employ high solid coating material with less tendency to flow away from edges. In this study, two coatings  are selected and evaluated in terms of their edge retention ability.

Corrosion Under Insulation (CUI) in pipingc systems consumes a significant percent of the maintenance budget in the petrochemical industry. Prevention of CUI by the use of (1) thermal spray aluminum, (2) stainless steel pipe, (3) expanded metal cages for personnel protection instead of insulation and (4) aluminum foil wrapping are discussed in terms of long term protection, installed cost and Life cycle cost.

The nut and bolt thread protector system is a patented, ultraviolet stabilized polyethylene thread protector, which seals nut and bolt threads in pressurized grease to effectively prevent corrosion and provide protection against physical damage.

Since 1982, there has been a move to Thermal Sprayed Aluminum (TSA) coating in the “splash zone” of offshore structures.  Our experience indicates that an experience applicator, good surface preparation and quality of wire combined to achieve required thickness and apply the sealer to seal the entire surface.

A two-year study of corrosion and protection of ductile iron pipe. Field and laboratory evaluations of short and long term polarization rates. Corrosion rate reduction and cathodic current criterion. Benefits of the traditional, standard asphaltic shop coating. A database of 1379 inspections of buried iron water lines. Result: A risk based protection design strategy for buried ductile iron pipelines.

As corrosion control thermal spray jobs are more frequently specified, more painting contractors are adding thermal spray application to their businesses. Facility owners as well as contractors need to define what issues are critical for training the corrosion control thermal spray operators.

This paper will consider the performance and relevance to static situations of the key types of Cathodic dip painting (CDP) Antifoulings (Rosin Modified types), the current tin free polishing types (typically acrylates of various types), and low energy surface types. Both field experience and laboratory work will be considered.

This paper will critically review the current philosophies described in  ISO and NACE anti-corrosive performance test standards, taking into consideration correlation with natural exposure, track record, validity of "acceptance" or "pre-qualification criteria", dry film thickness and suggested areas for improvement.