Corrosion of OCTG
Date:2016-03-29 Views:762Time(s) Label:Corrosion of OCTG
OCTG corrosion situation
of oil, casing,
gathering pipeline and storage tank corrosion is mainly oil and gas well
output, shallow water, such as injection fluid corrosion, the main media such
as H2S, CO2, dissolved oxygen and SRB.Tend to drill the role of many of the
media, including drilling, pitting corrosion and corrosion fatigue, gravity
stretching and rotating stress corrosion damage and fracture, etc.
OCTG corrosion characteristics of produced water has a sulfate-reducing
bacteria, under deposit corrosion and erosion threaded carbon dioxide,
bicarbonate and chloride ions, common causes of corrosion. When hydrogen
sulfide occurs when the well (especially gas), tubing destroy hazardous
characteristics, corrosion damage is mainly due to hydrogen embrittlement HIC
and SSCC. Tubing in weight, under external pressure, and other factors in a
complex state of stress, tensile stress is an important factor to promote the
metal protective film and substrate corrosion damage. Tubing and gathering
pipelines there fouling, when there Sr2 +, Ba 2+ dirt when not use conventional
methods to clean pickling, seriously affecting the normal production. Tubing
and gathering pipelines exist wax phenomenon, high frequency wax job seriously
affect the normal production. Tubing and gathering pipelines of erosion-corrosion
is a common form of corrosion failure, abrasive, cavitation, etc.
1) take appropriate and effective protective coating. Such as corrosion
protection coatings and metal coating technology;
2) take other auxiliary instruments: such as adding inhibitor and a closed
water system, reducing the amount of dissolved O2, CO2, H2S; the use of
sulfate-reducing bacteria fungicides.
3) the use of cathodic protection, corrosion monitoring systems established to
grasp the dynamic corrosion, preventive measures.