钻井液与完井液2016，Vol.33Issue(6)：51-57,7.DOI:10.3696/j.issn.1001-5620.2016.06.009
甲酸盐对套管/油管腐蚀速率评价方法与影响因素
Method of Evaluating Corrosion Rate of Formates to Casing and Tubing Strings and the Influencing Factors
杨向同 1肖伟伟 2刘洪涛 1徐同台 2谢俊峰 1张瑞芳2
作者信息
- 1. 新疆库尔勒塔里木油田油气工程研究院,新疆库尔勒841000
- 2. 北京石大胡杨石油科技发展有限公司,北京102200
- 折叠
摘要
Abstract
Standard method for evaluating the corrosion rate of formatesis not presently available.A method of evaluating the corrosion rate of formates to casing / tubing strings has been presented with an idea borrowed from the methods of evaluating the corrosion rate of metals.In laboratory experiment,metal coupon weight loss method and a CGF-II HTHP static corrosion tester were used to study the influencing factors such as the type of the formate,production technique,pH,steel material quality,density,and retarder etc.It has been found that using TPl40 steel coupon,the corrosion rate of sodium formate was more than 2 times that of potassium formate,because the C1 content in sodium formate (0.619％) was greater than the Cl content in potassium formate (0.0243％).For potassium formate,different production processes resulted in different sulfur contents;potassium formate A contained 0.18％ sulfur,far more than that of potassium formate B (0.0477％) and potassium formate C (0.046％),and thus,the corrosion rate of potassium formate A was much higher than that of the latter two.The corrosion of formate salts to steel is much severe under acidic conditions.Water solutions of formate salts taken from a well site needed to be buffered with sodium carbonate and sodium bicarbonateor potassium carbonate and potassium bicarbonate.The corrosion rate of TP140 steel in potassium formate solution was 20 times of the steel BG 13 Cr or JFE 13Cr,indicating that potassium formate had lower corrosion rate to stainless steel than to carbon steel.Since high concentration of HCOO-is good for the protection of steel,the corrosion rate of TPl40 steel in 1.20 g/cm3 potassium formate solution was more than 2 times of the corrosion rate of TP140 in potassium formation solution of 1.40-1.57 g/cm3.Thus,corrosion inhibitors should be used when low density formate muds are used.Based on these experimental data,the use of corrosion inhibition measures can be justified when using formate drilling fluids.关键词
甲酸盐钻井液/腐蚀速率/套管/油管Key words
Formate drilling fluid/Corrosion rate/Casing/Tubing分类
能源科技引用本文复制引用
杨向同,肖伟伟,刘洪涛,徐同台,谢俊峰,张瑞芳..甲酸盐对套管/油管腐蚀速率评价方法与影响因素[J].钻井液与完井液,2016,33(6):51-57,7.
