几种投球滑套球座材料的冲蚀性能试验研究

Experimental Study on Erosion Behaviors of Several Materials of Sliding Sleeve Ball Seat

水力喷砂压裂会对投球滑套球座造成很严重的冲蚀磨损,从而导致坐封失效。为此,对35CrMo、42CrMo、45#、球墨铸铁和WC球座材料的冲蚀磨损进行试验研究,得到如下结论:塑性材料的冲蚀率随冲蚀角的变化规律相同,均在30°附近呈现最大值; WC涂层冲蚀率随冲蚀角的增大而增大,在冲蚀角90°时出现最大值,当砂浆质量分数较小时,冲蚀率随砂浆质量分数的增大而增大,在15%附近达到峰值,但当质量分数继续增大时,材料的冲蚀率趋于稳定;在同等试验条件和小冲蚀角情况下,5种球座材料试样的冲蚀率从大到小依次为球墨铸铁、45#、35CrMo、42CrMo、WC,可将WC通过热喷涂工艺喷涂到球墨铸铁表面形成涂层来提高其抗冲蚀性;当冲蚀角小于45°时,45#材料表面的冲蚀破坏形态主要以犁沟为主,当冲蚀角大于45°时,冲蚀破坏形态主要以塑性变形为主;当冲蚀角较小时,WC材料的抗冲蚀性优异,材料表面存在细而浅的犁沟,当冲蚀角变大时,凹坑的数量、面积和深度也变大。研究结果对于压裂作业的正常进行具有重要意义。

Hydraulic blasting fracturing would cause severe erosion and wear on the ball seat of the sliding sleeve,resulting in failure of ball setting.To address the problem,the erosion wears of ball seat materials of 35CrMo,42CrMo,45#,ductile iron and WC were studied.The conclusion is as follows:the erosion rates of plastic materials have the same variation trend with the erosion angle,which shows the maximum erosion rate around the erosion angle of 30°.The erosion rate of WC coating increases with the erosion angle,and the maximum value appears at the erosion angle of 90°.When the mass fraction of sand slurry is small,the erosion rate increases with the mass fraction of sand slurry,and reaches the peak around mass fraction of 15%.But when the mass fraction continues to increase,the erosion rate of the material tends to be stable.Given the same experimental conditions and small erosion angle,the erosion rate rank of the five material samples,from high to low,is ductile iron,45#,35CrMo,42CrMo and WC.WC can be sprayed onto the surface of ductile iron by thermal spraying to form a coating to improve the erosion resistance of ductile iron.When the erosion angle is less than 45°,the erosion damage morphology of the surface of 45#material is mainly furrow.When the erosion angle is larger than 45°,the erosion damage is mainly plastic deformation.When the erosion angle is small,the WC material has an excellent erosion resistance with fine and shallow furrow on the surface.And the number,area and depth of pits would become larger with the erosion angle.