NACE Specification

In order for the lining material to obtain maximum adhesion to the substrate surface, it is essential that the surface be absolutely clean. All steel surfaces to be lined must be abrasive blasted to a white metal in accordance with SSPC Specification SPS-63 or NACE Specification 1. A white metal blast is defined as removing all rust, scales, paints, and so on to a clean white metal that has a uniform gray-white appearance. No streaks or stains of rust or any other contaminants are permitted on the surface. At times a near-white blast cleaned surface equal to SSPC-SPIO may be used. Since this is less expensive, it should be used providing the lining manufacturer permits it. 

Chemical cleaning implies the removal of material from the surface of the specimen by dissolution in an appropriate chemical agent. Solvents such as acetone, carbon tetrachloride, and alcohol are used to remove oil, grease, or resin and are usually apphed prior to other methods of cleaning. Various chemicals are chosen for appheation to specific materials some of these treatments in general use are outlined in the NACE standard. 

Tipps, C. W., Protection Specifications for Old Gas Main Replacements , Paper No. 27, Corrosion/70, NACE, Houston (1970)... 

Comprehensive tables of materials susceptible to stress corrosion cracking in specific chemicals are given by Moore (1979). Moore s tables are taken from the corrosion data survey published by NACE (1974). 

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 ... 

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/ISO 15156 (1-3), however, is more difficult to interpret and does not address SRVs specifically. From this edition, different manufacturers (and users) may and will select different (more standard and/or exotic) materials, while both groups claim to comply with the standard based on their own interpretation. 

Some specifics about this new NACE version ... 

Refinery applications have always been outside the scope of the NACE MR0175. However, this standard has frequently been used as a reference - NACE MR0175 has always been a little over the top for refinery use Sulphide couosion cracking is not such a concern downstteam (refineries have reduced chloride levels). Therefore, NACE decided to formulate a new refinery-specific standard inclusive of sulphide couosion cracking to meet the specific needs of the oil refining industry. 

Although the quality of the springs over the years has improved tremendously, they are subject to corrosion and it is important that their material selection is done properly for the process or that they are coated or treated correctly. Do not confuse, for example, aluminium paint with the higher specification (for NACE-level 2) six layers of cold-sprayed aluminium (called aluminized springs). 

Experience is sometimes codified in the form of industry guides that address generic, industry-wide corrosion problems. More commonly, experience takes the form of corporate experience of materials performance in specific applications, obtained from the operation and inspection of existing equipment. This information may be accessible across corporate boundaries through informal industry networks, depending on its commercial significance, and electronic networks, such as CORROS-L (see www.jiscmail.ac.uk) and the NACE Corrosion Network (see www.nace. org), which are increasingly important. 

An overall kinetic model for the cracking of gasoils to gasoline products was developed by Nace, Voltz, and Weekman [15]. The actual situation was a catalytic reaction and the data were from specific reactor types, but mass-action type rate expressions were used and illustrate the methods of this section. 

K. C. Gear, Y. P. Virmani, Corrosion of non-specification epoxy coated rebars in salty concrete , Corrosion/83, NACE, Houston, Paper No. 114, 1983. 

There are many studies covering the mechanism of corrosion in concrete and assessment techniques (1-6). Specifications and recommended practices on how to select and apply repair methods (NACE SP1290 and 0390, BSEN 12696, BSEN 1504 and ACI222R-01) are given in the literature. 

NACE RP290 It is a shorter document than BSEN 12696 and is specifically concerned with control criteria which are at the front of the document in Section 2. The first criterion mentioned is 100 mV polarization development or decay to be measured between the rest , equilibrium , or natural corrosion potential and the instant off potential measured O.l-l.O seconds after switching off the system. The instant off potential is required to remove the iR drop ... 

As stated in the anode descriptions earlier, there are also two NACE test methods for cathodic protection anodes. These are TM 0294 on embeddable anodes (mixed metal oxide coated titanium, mesh, ribbon, tnbes, rods and conductive ceramic tubes) and TMO1105-2005 on organic-based condnc-tive coating anodes. In addition there is a specification for applying thermal sprayed zinc anodes to concrete American Welding Society (2002). 

If selected options are electrochemical and are not covered by ENl504 then go to the relevant European Standard as given in Chapter 7 (or use a NACE national or government agency standard or specification if more relevant of if a suitable EN document does not exist). 

In the 12 years since the first edition I have been fortunate to continue to work with many knowledgeable and experienced engineers and specialists on the committees of NACE, the Corrosion Prevention Association, Concrete Society, Institute of Corrosion, the Transportation Research Board and CEN. I must specifically acknowledge Andrew Trafford of Aperio who kindly supplied a lot of useful information as well as photographs about radar, radiography, pulse velocity, ultrasonic and impact-echo techniques. My thanks also go to my publisher, and to Nick Clarke whose helpful suggestions strengthened the first draft of the book considerably. 

The features described under (a) to (e) above are elements of EN ISO 14001 1996 and the European Community Eco-Management and Audit Scheme (EMAS), whereas the features (f) and (g) are specific to EMAS. These two standardised systems are applied in a number of IPPC installations. As an example, 357 organisations within the EU chemical and chemical products industry (NACE code 24) were EMAS registered in July 2002, most of which operate IPPC installations. 

In the case of cathodic protection a useful source of information was a study conducted by the National Association of Corrosion Engineers (NACE), concerning the dollar value of the influence of NACE members on the purchases of specific materials protection... 

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