In many real-life circumstances, chemical exposure triggers several chemical-mechanical effects that influence material service life to a significant extent. The modeling enables Akiet to virtually test these effects on the composite in any configuration and application to obtain quantitative insight in lifetime and eventual failure modes. With a chemical risk (bow-tie) analysis several scenarios, which will be modeled can be identified. To model long-term properties of Akiet HSCT pipe body and connections in the downhole environment a specialist Abaqus-Chemical FEM software package is used. The outcome of this modeling will be used to de-rate the “as new” performance and provide properties that are representative up to the end of well life.
Akiet uses CheFEM to quantify effects of chemical-thermal exposure on mechanical response of its High Strength Composite Tubular (HSCT). CheFEM is a novel simulation app developed by Composite Agency. The tool is based on fundamental mixing thermodynamics (enhanced Sanchez-Lacombe Equation of States) and FEM (Finite Element Method) mechanics. This approach allows us to analyse chemical resistance in terms of rigorously quantified mechanical response.
We have chosen for CheFEM, because its approach is comparable to selection and lifetime assessments of steel materials on basis of tabled corrosion rates. Composites are better resistant than rational steel alternatives, but due to higher complexity of those materials, composite designers often got wrapped up in ambiguous polymer resistance labels like: “highly resistant”, “slightly affected”, “significantly affected”, “severely affected”, etc. This status quo is past tense for Akiet’s structures since CheFEM rigorously determines the mechanical response.
Already in early stages of the HSCT development, Akiet has used CheFEM in conjunction with Abaqus FEA (for CAD generation and extensive mechanically oriented modeling). These tools have been integrated part in the product development cycle and Akiet’s laboratory testing procedures. Examples of environments evaluated are: high pressure, high temperature CO2, H2S, acidic and alkaline aqueous solutions.
CheFEM is applied by reputable companies like Shell, Exxon Mobil and Boeing. For more information, visit composite-agency.com
“Before we performed API tests for emission and structural failure on different candidate materials, we used CheFEM to simulate the real-life behavior. CheFEM saved us lots of money.”
Oil & Gas Materials Specialist
"With CheFEM we can get rid of arbitrary knock-down factors for the working strain of our composite in hygrothermal loading conditions."
Aerospace Composite Specialist
"CheFEM will certainly help us to predict the lifetime of Graphene-based Coatings."
Professor Rensellaer Polytechnic Institute (USA)
Back to all news