In this paper investigate the influences of dissolved CO2/H2S gases, crude oil velocity and temperature on the rate of corrosion of crude oil transmission pipelines of Maysan oil fields southern Iraq. The Potentiostatic corrosion test technique was conducted into two types of carbon steel pipeline (materials API 5L X60 and API 5L X80). The computer software ECE electronic corrosion engineer was used to predict the influences of CO2 partial pressure, the composition of crude oil, flow velocity of crude oil and percentage of material elements of carbon steel on the rate of corrosion. As a result, the carbon steel API 5L X80 indicates good and appropriate resistance to corrosion compared to carbon steel API 5L X60. The rate of corrosion acquired from the test in flow conditions is most significant than that in static conditions. The crude oil from Noor field has the largest value of corrosion rate, while the crude oil from Halfaya field has the lower value; other crude oils have moderate values. The dissolved CO2/H2S gases contribute by a low degree in internal pipeline corrosion because of the small concentrations.

The aim of this paper is to investigate and discuss the mechanisms of corrosion of epoxy coatings used for potable water tanks. Two distinct types of Jotun epoxy coatings: Tankguard 412 contained polyamine cured epoxy and Penguard HB contained polyamide cured epoxy, were tested and studied using the electrochemical impedance spectroscopic (EIS) method. The porosity of epoxy coatings was determined using EIS method. The obtained results showed that the two epoxy coatings have excellent behavior when applied and tested in potable water of Basrah city. Polyamine is more resistance to water corrosion compared to polyamide curing epoxy and has high impedance values. Microscopic inspection after test showed that the polyamine cured epoxy has blistering while the surface of polyamide cured epoxy showed pitting and blisters. Keywords: Corrosion mechanism , epoxy coats, porosity, potable water, , EIS method.

In this paper, the Weibull uni-axial and multi-axialthe distribution function for polyethylene pipes under pressure loadingwere developed and analyzed taking account of residual stress.The tensile test was achieved to determine mechanical properties andthe Weibull parameters. An experimental method using the hole drilling strain-gage method was used to measure the residualstresses in PE pipe and compare with that obtained fromnumerical finite element method (FEM). The obtained resultsshow that there is a convergence between uni-axial and multi-axialdistribution function, but multi-axial distribution function givelarge values compared to the uni-axial distribution function. It wasobserved that the residual stresses have influence on failureassessment diagram and cause translation from elastic-plasticfailure to brittle failure.

This paper studies the influence of temperature on the corrosion rate of coated AA6111 aluminum alloy used in vehicle bodies under static and vibration states. The vibration test system was collected laboratory and used for testing of five different types of paints (EASI, Numix, Lesonal, DENSO and Polaron paints) in the 5 % NaCl solution using immersion test method. Lesonal paint provided the best corrosion protection, while DENSO paints show large values of corrosion rate, other coatings exhibit moderate values. Model of paints corrosion was developed to characterize the corrosion processes occur at the surfaces. It is found that corrosion rate obtained at vibration cases is larger than static cases and vibration effect on the coating protection rate.

The present paper, deals with the influence of vibration and temperature on corrosion rate of ASTM A537 carbon steel used for crude oil storage tanks of Basrah oil fields in south Iraq. A mechanical vibration system equipped with temperature controller according to ASTM G32 standards test method was used to test and study the effect of vibration and temperature on the corrosion rates using immersion test method. Three types of crude oils: light, medium, and heavy crude oils were collected from tanks in southern Iraq. The experimental immersion test results demonstrated that the vibration increases the corrosion rate compared to static case. The light crude oil show larger values of corrosion and heavy crude oil show smaller values, while medium crude oil show moderate values.