The main products are:Slick Drill Collar,Spiral Drill Collar,Nonmagnetic Drill Collar,Heavy Weight Drill Pipe,square and hexagonal Kelly.是什么意思_The main products are:Slick Drill Collar,Spiral Drill Collar,Nonmagnetic Drill Collar,Heavy Weight Drill Pipe,square and hexagonal Kelly.在線翻譯_英語_讀音_用法_例句