ASTM_G_208_-_12.pdf

Designation:G20812Standard Practice forEvaluating and Qualifying Oilfield and Refinery CorrosionInhibitors Using Jet Impingement Apparatus1This standard is issued under the fixed designation G208;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers a generally accepted procedure touse the jet impingement(JI)apparatus for evaluating corrosioninhibitors for oilfield and refinery applications in defined flowconditions.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1141 Practice for the Preparation of Substitute OceanWaterD1193 Specification for Reagent WaterD4410 Terminology for Fluvial SedimentG1 Practice for Preparing,Cleaning,and Evaluating Corro-sion Test SpecimensG5 Reference Test Method for Making PotentiodynamicAnodic Polarization MeasurementsG16 Guide for Applying Statistics to Analysis of CorrosionDataG31 Guide for Laboratory Immersion Corrosion Testing ofMetalsG46 Guide for Examination and Evaluation of Pitting Cor-rosionG59 Test Method for Conducting Potentiodynamic Polariza-tion Resistance MeasurementsG96 Guide for Online Monitoring of Corrosion in PlantEquipment(Electrical and Electrochemical Methods)G102 Practice for Calculation of Corrosion Rates and Re-lated Information from Electrochemical MeasurementsG106 Practice for Verification of Algorithm and Equipmentfor Electrochemical Impedance MeasurementsG111 Guide for Corrosion Tests in High Temperature orHigh Pressure Environment,or BothG170 Guide for Evaluating and Qualifying Oilfield andRefinery Corrosion Inhibitors in the LaboratoryG184 Practice for Evaluating and Qualifying Oil Field andRefinery Corrosion Inhibitors Using Rotating CageG185 Practice for Evaluating and Qualifying Oil Field andRefinery Corrosion Inhibitors Using the Rotating CylinderElectrodeG193 Terminology and Acronyms Relating to Corrosion3.Terminology3.1 The terminology used herein shall be in accordance withTerminology D4410,Guide G170,and Terminology G193.4.Summary of Practice4.1 This practice provides a method for evaluating corrosioninhibitor efficiency in jet impingement(JI)apparatus.Themethod uses a well-defined impinging jet set up and mass lossor electrochemical techniques to measure corrosion rates.Measurements are made using three different experimentaldesigns and at several flow rates to evaluate the inhibitorperformance under increasingly severe hydrodynamic condi-tions.1This practice is under the jurisdiction of ASTM Committee G01 on Corrosionof Metals and is the direct responsibility of Subcommittee G01.05 on LaboratoryCorrosion Tests.Current edition approved May 1,2012.Published December 2012.DOI:10.1520/G020812.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Significance and Use5.1 Selection of corrosion inhibitor for oilfield and refineryapplications involves qualification of corrosion inhibitors in thelaboratory(see Guide G170).Field conditions should besimulated in the laboratory in a fast and cost-effective manner.5.2 Oilfield and refinery corrosion inhibitors should provideprotection over a range of flow conditions from stagnant to thatfound during typical production conditions.The inhibitors arenot equally effective over all flow conditions,so it is importantto determine the flow conditions in which they are effective.5.3 Severity of hydrodynamic conditions depends on thetype of laboratory methodology.Typically,rotating cylinderelectrode is effective up to 20 Pa of wall shear stress,rotatingcage(RC)is effective between 20 and 200 Pa of wall shearstress,and jet impingement(JI)is effective at wall shear stressabove 200 Pa(1)3of wall shear stress.5.4 The JI test system is relatively inexpensive and usessimple flat specimens.5.5 In this practice,a general procedure is presented toobtain reproducible results using JI simulating the effects ofdifferent types of coupon materials;inhibitor concentrations;oil,gas,and brine compositions;temperature;pressure;andflow.Erosive effects predominate when the flow rate is veryhigh(typically above 500 Pa)or when sand or solid particlesare present;however,this practice do