... -6/°C9.6 x 10-6/°COilpumping valve ball and valve seat are products widely used in the ... company manufactures series of high-precision oil pumping valve ball and valve seats. Material, stainless steel, ceramics, hard alloy ... Featured with high hardness, wear resistance ,wash resistance and corrosion resistance. We have a good reputation by the ... free to contact us! Oil-pumping valve ball and valve seat