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INNOVATIONS: PRESENT&FUTURE
Impact of Scraping Activities on Coated Pipelines Hassan Al-Sagour and Mana Al-Mansour Saudi Aramco, Dhahran - Saudi Arabia
hassan.sagour@aramco.com
This study was conducted to validate raised concerns on the possible damage scrapers could cause to internal pipeline coatings. The scope of this paper covers aspects of scraping activities, quality of pipeline internal coating, and the interface between them. The need for scrapers was questioned in the first place. Then, the design of different types of scraping tools was examined. Also, the qualification program of pipeline internal coatings was explored to determine whether such coatings could withstand abrasion forces associated with pigging activities. The study concluded that there is not enough evidence to prove a significant damaging effect of scrapers on pipeline coatings.
S
audi Aramco started to standardize the use of internal coating of
which had increased the total suspended solids (TSS) once again [2].
pipelines in 1988 [1]. Prior to that year, Saudi Aramco had used bare
Thus, Saudi Aramco switched to internally coating its pipelines which
carbon steel pipes for its water injection system, which was commissioned
was well justified economically compared to either the injectivity losses
in 1978 [2]. At first, the internal corrosion of pipelines generated
or cost of intensified water treatment [3]. At the time, Fusion-Bonded
significant amounts of iron products which started plugging well heads
Epoxy (FBE) coating had been already used for corrosion protection of
and hindered well injection rates [3]. To improve well injectivity, Saudi
pipe externals with excellent track records since the 1960s [4]. Therefore,
Aramco started in 1983 an intensified water treatment program using a
the decision was taken to apply coatings for the internal protection as
combination of biocides (1500 PPM) twice a week and a weekly scraping
well, given that treated seawater was less aggressive than soil in terms
[2]. This expensive treatment had resulted in great improvements by
of lower temperatures and lack of dissolved oxygen [3]. At a later stage,
1985. Yet, it was relaxed one year later in terms of dosage and frequency,
liquid epoxy coatings were used to coat the internal of field girth welds,
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N.38 - 2021 JUNE - ipcm® Protective Coatings
