The buckling behavior of rod strings in wellbore is one of the key issues in petroleum engineering. The slender rod strings in vertical wellbore were selected as research objects. Based on the energy method, the critical load formulas of sinusoidal and helical buckling were derived for the string with the bottom of the wellbore pressure. According to the sinusoidal and helical buckling’s geomet...

The main goal of this research is to extract the full mechanical properties of stitch biax and triax composite materials which are necessary for finite element analysis, based on limited available experimental data and without performing full static characterization tests. Utilized experimental data are limited to elastic modulus of two 0o and 45o directions. Using presented technique and afore...

Waterborne Epoxy based coatings were prepared by using a water-borne epoxy resin and a suitable hardener. The formulation and optimization procedure were carried out on the bases of experimental designs by the mixture design technique in which the important paint properties are modeled by using special cubic model. The corrosion behavior of these coatings was investigated using electrochemical ...