科学超深井钻探铝合金钻杆的腐蚀失效分析

Analysis on Corrosion Failure of Aluminum Alloy Drill Pipe for Scientific Ultra-deep Well Drilling

针对铝合金钻杆在复杂的超深井钻井工程服役条件,分析了铝合金钻杆腐蚀行为的主要外在钻井工程因素,并进行了松辽盆地资源与环境深部钻探"松科二井"铝合金钻杆工程试样腐蚀程度的测试与分析。分析结果表明:钻杆结构、磨损与应力、钻井液介质、井内高温高压是其产生腐蚀的主要服役条件因素;铝杆体与钢接头连接处的腐蚀情况最为严重,铝杆体次之,加厚端部分耐蚀性最好;腐蚀产物的主要成分是Al_2O_3和Al(OH)_3相。

In view of the service conditions of aluminum drill pipe in complex ultra-deep well drilling engineering, the main external drilling engineering factors of the corrosion behavior of aluminum alloy drill pipe are analyzed, the test and analysis on corrosion degree of the aluminum drill pipe engineering sample of Songke - 2 well in the project of deep drilling of resources and environment in Songliao basin. The results show that the structure of drill pipe, wear and stress, drilling fluid medium as well as high temperature and high pressure are the main factors of corrosion; the corrosion at the connection point of aluminum rod and steel joint is the most serious and the aluminum rod body is the next; the corrosion resistance of pipe upsetting end is the best, the main components of the corrosion products dare Al2O3 and A1 （OH） 3 phase.