Development And Tribological Properties Of Nylon Matrix Composites For Sucker Rod Centralizer

As called"the industrial blood",its high-efficiency mining is related to the lifeline of the national economy,and the dominant pumping method of the rod pump is deeply affected by the partial wear between the rod and the tube,which seriously affects the oil production efficiency and mining cost.Among the many ways to solve this problem,the use of a nylon-based sucker rod centralizer is extremely effective.Nylon has high water absorption rate and poor wear resistance,therefore,it is of great practical significance to study a special material for sucker rod centralizer with low water absorption,good mechanical properties and high wear resistance.In this paper,16 kinds of PA66/GF/CF composite and 16 kinds of PA66/GF/Nano-Al₂O₃ composite was prepared by extrusion granulation-injection molding process using nylon 66?PA66?as the matrix,carbon fiber?CF?,glass fiber?GF?and Nano-alumina?Nano-Al₂O₃?as filling materials.The water absorption,hardness,compressive strength,friction coefficient and wear rate of the materials were measured.The surface morphology of the composites after friction and wear was observed by scanning electron microscopy?SEM?.The energy was analyzed by energy dispersive spectroscopy?EDS?.The material transferation between the dual test pieces was analyzed.The effects of the contents of CF,GF and Nano-Al₂O₃ on the properties of the composites were systematically studied.The wear mechanism of the two composite materials is analyzed in the water-lubricated environment rubbing with J55 alloy steel.The test results show that the addition of the three additives CF,GF and Nano-Al₂O₃have positive effects on water absorption,hardness,compressive strength,friction coefficient and wear rate of the composite.Comparing these performance parameters of two composite materials,the water absorption of the PA66/GF/CF composite is lower than that of the other one composites,of which the G20C18 reach the lowest to be 0.21%.The hardness of the PA66/GF/Nano-Al₂O₃ composite is higher than that of the other one composites,of which the G15A7 reach the highest to be 93HSD.The compressive strength of the PA66/GF/CF composite is higher than that of the other one composites,of which the G20C18 ratio material is up to 147 MPa.The friction coefficient of PA66/GF/Nano-Al₂O₃ composites is lower than that of the other one composites,of which the G20A7 composites reach the lowest to be 0.0617.The wear rate of PA66/GF/CF composites is lower than that of the other one composites,of which the G20C15 reach the lowest to be 5.3014×10^-5mm³·?N·m?^-1.As the content of added materials increases,the wear of PA66 composites changes from adhesive wear to fatigue wear and abrasive wear.