Smart pigs

Smart memory alloys Smart pigs Smart polymers... 

Between 1985 and 1991,1726 natural gas pipeline ruptures andleakages were reported in the United States. These incidents resulted in 634 injuries and 131 fatalities. Third-party damage was the most common cause of these incidents, followed by corrosion. The GAO believes that the corrosion-related incidents can be reduced with the use of smart pigs (46). U.S. DOT 1992 accident statistics showed that 52.5% of U.S. oil spills involving loss of at least 1590 m3 came from pipeline accidents, comparable to the worldwide statistic of 51.5%. The U.S. DOT regulated 344,575 km of liquids pipelines during the 10-yr study period and received reports on 1901 accidents during that time thus the number of failures per year per 1000 miles was 0.888, of which 27% was due to corrosion and 31% to outside forces (48). 

Inspection pigs (also referred to as in-line inspection pigs, smart pigs, and intelligent pigs ) are used to collect data (including, but not limited to, corrosion) from within the pipe using two methods ... 

The term smart pig refers to the tools containing sophisticated electronics, and it is different from more conventional pigs—such as cleaning (i.e., poly, brush, bullet, etc.), gauging, or batch pigs— that are simple mechanical devices run in pipelines for various purposes. - ... 

As seen from Figure 4.39, this pig type has three main components. One component is used for mechanical driving of the whole device. The other two are used to collect and record data. In fact, these two components are the brain of the smart pig. They work in accordance with mathematical software that processes the input data. It is this mathematical software that sees defects, including but not limited to pitting and cracks. 

Pigging by itself is one of the best ways to physically remove biofilms, and when it is combined with a sophisticated technology to collect data, it may sound like the best technically achievable method, especially in terms of MIC likelihood prediction. Nevertheless, it is important to vmder-stand that although smart pigs are among the best techniques that industry has been plying to... 

FIGURE 4.40 Some of important pros and cons of smart pigs. (Adapted from Roche M. et al., Intelligent pigging policy, Recent experience and needs of a petroleum operator, Paper No. 49, Corrosion 96, NACE,... 

Some of the pros and cons of smart pigs are summarized in Figure 4.40. ... 

R.B. Kuprewicz. Observations on the apphcation of smart pigging on transmission pipehnes. September 5, 2005. http //pstrust.org/library/docs/. Accessed on September 5, 2011. 

They are very much in the public domain. Chemical plants, refineries, and onshore oil and gas facilities are mostiy located in a relatively small area that is fenced off, often with tight security. Offshore oil and gas facilities are usually out of sight of the public. But pipelines are almost entirely in public areas, with the exception of terminals and pumping stations. Also many pipelines are buried so detecting a leak can be difficult, particularly if the pipe is not designed to handle smart pigs. 

PermaWrap uses a two-part adhesive system and a rigid fiberglass sleeve (Fig. 18.15). The adhesive system bonds the PermaWrap sleeve to the pipe surface. High compressive strength putty is used to fill the cavities and dented areas it serves to transfer the load from the pipe surface to the PermaWrap repair sleeve. The sleeves come in various widths (from 6" (150 mm) to 18" (457 mm)). The main featnre of PermaWrap sleeve repair is that it can be detected by a smart pig or magnetic flux leakage tool. 

Pipeline corrosion can be monitored by pushing "smart pig instruments through the line to measure local and general metal loss (by electromagnetic means). Related instruments have been developed that can make ultrasonic measurements of wall thickness. These methods are used to detect the presence of both external corrosion and internal corrosion. In some instances, video camera techniques can be used to evaluate the condition of internal pipe surfaces. Caliper typ>e measurements can be made in those relatively short lines that permit use of a cable to pull the instrument... 

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