PredictPipe 3.0 uses a complex computational model for determining
the corrosion rate, the ease-of-use in applying the system to obtain
meaningful answers is transparent. In the following description,
we will go through a typical consultation in a step-by-step manner
The user can
specify data for any of the parameters and watch the effect of that
parameter on the corrosion rate in the system instantaneously. The
system starts with a set of default values and calculates a corrosion
rate based on any changes to the displayed values. A typical consultation
will involve the following five steps:
Specification of Production Data: This is the first step
to begin a consultation. The production data in terms of Gas Production,
Total Water Production (used to compute phase behavior) and Oil
Production Rates can be entered. H2S and CO2 mol% can also be entered
at this stage. The convert button serves to view the ratios, partial
pressures, and superficial liquid velocity as computed dynamically.
Clicking on OK stores this information and updates the main screen
with these values as well as performs phase behavior computations
to predict existence of liquid phase.
Specification of Water Analysis data: The Water Analysis
Screen can be used to input data relevant to different cations and
anions (16 species) from your water analysis.
Chlorides/oxygen/ sulfur: Chlorides and sulfur typically
make corrosion worse if the process has been initiated by the presence
of acid gases. Their role, while not as critical as that of H2S
or CO2, is significant because these parameters can significantly
increase corrosion rates in mildly corrosive systems. Presence of
oxygen beyond 20 ppb even in mildly acidic systems can lead to significant
corrosion rates, especially with high chlorides and high flow rates
at elevated temperatures.
Analysis: Clicking on the Pipeline Analysis buttons displays
the Pipeline Profile Inputs Screen used to perform ICDA. This tool
performs comprehensive flow modeling for the pipeline system provided
to generate the corrosion distribution profile, water holdup and
critical angle values. The pipeline geometry can be input by typing
in the lengths and inclinations of up to 8 segments or by importing
a CSV or MS Excel file.
geometry input will generate the overall graphical view of the piping
system as shown below. Using the arrow keys to select the segment,
detailed parameters about the segment can be viewed. The segment
selector moves along the pipeline marking the current segment selected.
The color of the selector and the angle changes to red to mark the
segments with angles greater than the critical angle and hence susceptible
to internal corrosion.