NACE requirements

One important check in pipeline design is the checking of NACE (National Association of Corrosion Engineers) requirements. According to Section 1.3.1.1, NACE applies when the partial pressure of H2S in a wet (water as a liquid) gas phase of a gas, gas condensate, or crude oil system is equal to or exceeds 0.0003 MPa abs (0.05 psia). 

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Sour gas applications Here, NACE recommendations (see Section 4.4) should be followed. Most wrought grades are acceptable to NACE. Therefore, in general, duplex valves with bar stock nozzles and discs will meet NACE requirements. Some limited cast grades will generally comply also ... 

The concentration of hydrogen sulfide is used to establish the NACE requirement. This information is not used to calculate the actual corrosion rate. 

In the sulfide stress cracking region, appropriate metallurgy is required in line piping, pressure vessels, etc. There is a listing of acceptable steels in the NACE standard. Steels with a hardness of less than 22 Rockwell C hardness should be used in areas where sulfide-stress cracking is a problem. 

For sour service, National Association of Corrosion Engineers (NACE) MR-01-75 requires that steel material have a Rockwell C hardness of less than 22 and contain less than 1% nickel to prevent sulfide stress cracking. 

Metallurgical and Inspection Requirements for Cast Sacrificial Anodes for Offshore Applications, RP-0387-87, NACE, Houston (1987)... 

Wood, one of people s oldest materials, remains an important (and too often, overlooked) corrosion-resistant material of construction in the chemical-process industry. Wood tanks and wood piping have long met engineers requirements for dependable service and excellent performance in industrial applications. A very thorough and detailed treatise can be found in a three-part publication, by Oliver W. Siebert, Wood—Nature s High-Performance Material, NACE, Materials Ferformance, vol. 31, nos. 1-3, January through March 1992. ... 

Although no ASTM ferrous metal corrosion specification exists now for gasoline, diesel fuel, and other fuels, many refiners and marketers have adopted the National Association of Corrosion Engineers (NACE) Corrosion Standard Method TM-01-72-93 as a specification. This method has also been utilized by most product pipeline companies and is an established requirement. The NACE corrosion method is summarized as follows ... 

The NACE corrosion scale is a visual rating of surface rusting from 0% to 100%. Most refiners, product pipeline companies, and marketers of fuel require an NACE surface rust rating of 5% or less. The NACE corrosion rating scale is outlined in TABLE 7-1. 

Compliance with NACE is a frequent requirement for valves, especially in the modem oil and gas industry. Because NACE has already changed a couple of times in the early twenty-first century, there tends to be some confusion as to which code exactly to apply where. 

This standard was and still is widely used by operators, either in the oil and gas production fields or refineries. Most SRV manufacturers have established a standard Bill of Materials that complies with the minimum requirements of NACE MR0175, taking into account certain specific valve material selections based on their hardness and under the condition of the following operating conditions ... 

The NACE MR0175-2002 was treating only the level of H2S in fluids and, as mentioned, most SRV manufacturers simply established a NACE bill of material for their products which complied with the requirements of that NACE edition. 

NACE Standard MR175-90, Standard Materials Requirements-Sulfide Stress Cracking Resistant Metallic Materials for Oilfield Equipment, NACE International, Houston, TX, 1990. 

EFW Open hearth, electric far-nace or oxygen converter. Electric fii-sion weld (single or double side) Not required... 

Bridge decks, parking structures, and other reinforced concrete structures lend themselves to cathodic protection, particularly when the concrete is contaminated with cathodic chlorides from deicing salts or a marine environment. Special techniques are required as described by Rog and Swait [71] NACE [72, 73] and Morgan [74]. 

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