Prestressed concrete cylinder pipe pipeline sections projected to exhibit wire breaks were detected - and one not so - were excavated, removed, inspected, and dissected. Corrosion had initiated upon the inner surface of shorting straps and spread to the prestressing wires. A mechanism for this corrosion is presented and the findings discussed.
The objective of the research summarized in this paper was to define pipeline conditions where use of the 100-mV polarization criterion may be conducive to possible SCC problems. Paper Number 01592, presented at Corrosion/2001, summarized Part 1 of the research, in which the previous research results were analyzed. In this paper, the results of the laboratory testing are presented.
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.
A simulation software for the cathodic protection (CP) of underground pipeline networks is presented. In this paper, the software will be applied to two different cases. The first concerns the design of the cathodic protection of a 55 km pipeline section. The second is the evaluation of an existing pipeline network in the north-west of The Netherlands.
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.
This paper describes the relevant characteristics of available joint coating types and examines different testing protocols to explore these characteristics. The objective is to assist in the selection of appropriate, practical, cost effective girth weld protective coatings. that will provide good long-term corrosion protection.
Numerous studies and papers have addressed the need and technical merits of various external corrosion protection scenarios for ductile iron pipe. Most recently, a Design Decision Model was developed to select the optimum method of corrosion protection, considering both the likelihood and consequence of failure.
Currently, a number of fracture mechanics-based methods are available for crack assessment. In this paper, a critical review is given to failure assessment diagram (FAD), in particular the API 579-2000 fracture mechanics assessment method for crack-like flaws. Illustrations, arranged by applicability to field examples, demonstrate the approach.
This paper begins with a brief discussion of essential properties of all pipeline coatings, and a listing of multi-layer systems designed to meet specific needs. It then focuses on special considerations regarding application parameters for multi-layer systems that use fusionbonded epoxy as the primer.