抽油杆和油管材料在油田污水介质中的摩擦磨损性能研究

Friction and Wear Behaviors of Sucker Rod and Tubing String in the Presence of Oil-Field Wastewater as the Lubricating Medium

以油田污水作为润滑介质,利用MG-200型高速高温摩擦磨损试验机考察了45#钢抽油杆同表面喷焊不同厚度耐磨涂层的J55油管配副时的摩擦磨损性能,采用扫描电子显微镜观察了抽油杆试样磨损表面形貌.结果表明,在油管试样表面引入适当厚度的喷焊耐磨涂层可以显著提高摩擦副的耐磨性能,并在一定程度上降低摩擦系数,从而有利于减小抽油杆同油管之间的摩擦力,提高抽油杆和油管的使用寿命;45#钢抽油杆试样同J55油管试样配副时主要发生粘着磨损,而同表面涂覆耐磨涂层的J55油管试样配副时粘着磨损明显减轻;J55油管试样在常温和60℃下的磨损率相近,而45#钢抽油杆试样在60℃下的磨损率稍大,这可能是由于60℃下粘着磨损有所加剧并发生轻微腐蚀磨损所致.当耐磨涂层过厚时,其减摩抗磨作用显著减弱,故应当适当控制油管表面耐磨涂层的厚度,以充分发挥其减摩抗磨作用.

An MG-200 high speed and high temperature friction and wear tester was performed to evaluate the friction and wear behaviors of AISI1045 steel sucker rod sliding against J55 tubing string and J55 tubing strings coated with spray-welded wear-resistant coatings of various thickness in a ring-on-ring configuration and under the lubrication of oil-field wastewater as the lubricating medium. The worn surface morphologies of the steel sucker rod specimens coupled with the J55 tubing string and the J55 tubing string coated with the wear-resistant coating were observed using a scanning electron microscope. As the results, it was effective to increase the wear-resistance of the frictional pair by introduction of the wear-resistant coatings on the tubing string surface. The wear-resistant coating of a proper thickness also contributed to reduce the friction coefficient to some extent, which was helpful to reducing the friction force between the sucker rod/tubing string pair and increasing the service lifetime of the pair. The decreased wear rates of the sucking rod specimens coupled with the tubing string specimens coated with the wear-resistant coating of a proper thickness were attributed to the action of the coating in decreasing adhesion wear. Moreover, the tubing string specimen recorded little difference in wear rate at room temperature and 60°C. However, the sucker rod specimen registered a slightly larger wear rate at 60°C than at room temperature, which could be attributed to the enhanced adhesion wear and mild corrosive wear at elevated temperature. It was imperative to properly control the thickness of the wear-resistant coating on the tubing string surface so as to bring its friction-reducing and antiwear action into effect.