Pipeline materials

Here the electrical resistance of the pipeline material d is pipe... 

The normal industrial practice for controlling the internal corrosion of petroleum pipelines is to use coatings, nonmetallic pipeline materials, or corrosion inhibitors. Corrosion inhibitors, which are used for the protection of oil pipelines, are often complex mixtures. 

Adams, T. Evaluation of natural gas pipeline materials and infrastructure for hydrogen/ hythane service, FY 2006 Annual Progress Report, III.A.4, 2006. 

Integrity management processes should take into account the embrittlement effects of dry hydrogen gas on carbon steel pipeline materials and welds used to join pipe sections. 

This table is split into two tables by usage Table IX-3 A, Basic Quality Factors for Longitudinal Weld Joints in Pipes, Tubes, and Fittings, Ey and Table IX-3B, Longitudinal Joints Factors for Pipeline Materials. 

Table IX-3B Longitudinal Joints Factors for Pipeline Materials...

Table IX-5A Carbon Steel Pipeline Materials Performance Factor, Hf...

Based on the flow equation some essential economic aspects can be derived. First, the investment cost of a pipeline is obviously linked to the diameter of the pipeline. The larger the diameter, the more steel is needed, and the more weight the pipeline will have. This implies that investment costs increase with increasing diameter as costs for pipeline material and installation will increase. As we can see from the equation however, the output (flow) will increase in the power of 2.5 for every unit of diameter invested. This economic fact is often referred to as economy of scale. 

It is believed that this can be related to the differences in coefficient of restitution between the conveyed particles and the pipeline walls. On impact with the rubber, the particles will be decelerated, since the rubber will absorb much of the energy of impact. As a consequence, the particles will have to be re-accelerated back to their terminal velocity. The coefficient of restitution of the particles against the steel pipeline wall will be very much lower. This effect is clearly magnified by increase in velocity and explains why there is little difference between the two pipeline materials in low velocity dense phase conveying, but differ by 50% in high velocity dilute phase conveying. The results obtained with the barite were very similar. 

P. Marjanovic, D. Mills, J.S. Mason, The influence of pipeline material on the performance of pneumatic conveying systems, Proceedings of the Pneumatech 4, Glasgow, UK, June 1990, pp. 45.3 464. 

The ASTM Corrosion Test procedure by Total Immersion Method requires that all specimens in a test series should have the same dimensions when comparisons are to be made. In these experiments, carbon steel was used representing the pipeline material. The coupons were cleaned, polished and weighed. Coal-water slurry, 10 to 40 weight percent, was used in the corrosion tests. For the coal-water slurry the intitial pH of the medium varied from 2.3 to 2.6 and the test series containing the nutrient media, the microorganisms and the inhibitors the pH varied from 2 to 2.5. Specimens were immersed in the reaction vessel maintained at a constant temperature of 86°F for 72 hours or the specified time. The coupons were removed, washed with deionized water, dried and weighed. The loss in weight of the specimen, before and after the test was attributed to corrosion. 

Bomberger, D.R., "Hexavalent Chromium Reduces Corrosion in Coal-Water Slurry Pipeline. Materials Protection, Vol. 4, pp. 43-49, 1965. 

A. Punter, A. T. Fikkers, G. Vanstaen. Hydrogen-Induced Stress Corrosion Cracking on a Pipeline. Materials Performance 31(6), 24 (1992). (Proceedings of the Pipe Protection Conference, Cannes, France, 1991.)... 

If and when extensive new hydrogen transmission pipelines are needed in the decades ahead, research in such areas as lower-cost pipeline materials, technology for dual-use natural gas-and-hydrogen pipeline connection techniques, layout optimization, and even pipeline emplacement technologies may be of significant value. However, the committee sees this as a priority research area only to the extent that such efforts directly benefit distributed production techniques, which are expected to dominate over the next 20 to 30 years. 

Crude oil contains a number of metallic elements which are of interest either due to the undesirable effects they cause in the refining process or as an indication of the origin of the oil. The concentration levels encountered will vary with the type of crude oil. Crudes originating from different oil fields may vary markedly in trace-metal content. Also some crude oils will become contaminated in transport from the oil well to the refinery by, for example, pipeline material or seawater. The levels of such metals as Ni, V and Na must be carefully controlled in order to reduce production problems such as plant corrosion or catalyst poisoning. 

Adams, T.M., R. Sindelar, G. Rawls and P.-S. Lam (2005) Evaluation of natural gas pipeline materials for hydrogen/mixed hydrogen-natural gas service , November, available at http //www.hydrogen.energy.gov/pdfs/progress05/ v a 4 adams.pdf (accessed March 2008). 

Soft waters attack pipeline materials and cause extensive leakage in many drinking water pipe systems. In this connection it has been recommended that the ratio between the concentration of bicarbonate HCO3 and the concentration of SO/ and Cr, respectively (in mg/1) should be higher than 1. The pH value should be between 7.4 and 8.3, the oxygen content about 6 mg/1, and the water velocity > 0.5 m/s. The bicarbonate content should normally be increased to 50-60 mg/1, e.g. by addition of CO2 and calcium compounds. 

R. Javaherdashti, E.G. Marhamati. A computerized model incorporating MIC factors to assess corrosion in pipelines. Materials Performance, Vol. 44, No. 1, pp. 56-59, January 2005. 

The temperature of the soil as well as the temperature of the pipe may create favorable conditions for attack on pipeline materials. Liquid and gas lines have slightly different operating temperature characteristics, but both are still susceptible. For example, with gas pipelines, both the pipe and surrounding ground can vary from a high of 40°C upon leaving the compressor station down to 5°C at distances from the station. 

Material selection is an optimization process the material selected for an application must be chosen for the sum of its properties. Many factors have to be considered in pipeline material selection, such as its suitability toward process requirements, type of fluid to be used, and flow characteristic. 

Klechka, E.W. 2001. Use of corrosion inhibitors on the Trans Alaska pipeline. Materials Performance 40 (Suppl. 1), pp. 7-9. 

Piping design criteria, including a library of pipeline material specifications, and the minimum contents outlined in Chapter 14. 

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