Method for fabricating graphite filled sintered metal seats for ball valves

摘要

A valve seat for ball valves comprises a ring-shaped or annular body fabricated of sintered metal particles having interparticulate spaces which are substantially completely filled with graphite. The seat is fabricated by pumping a dispersion of colloidal graphite in a liquid carrier through the matrix of a preformed ring-shaped sintered metal body, thereafter heating the body to drive off any portion of the liquid carrier which remains in the interparticulate spaces of the body, and then coining the body to collapse any voids which remain in the body and to mechanically bind into the body the graphite which has been trapped in said interparticulate spaces during the pumping step.