Protector is a device designed to prevent entering of formation fluid into inner cavity of electric motor and oil leakages (serves as sealing); to transfer rotary moment to the shaft of ESP; to accommodate temperature expansion of oil volume inside inner cavity of electric motor (surplus of oil is thrown out to annular space of the well through the valves) and to equalize pressure inside engine cavity with pressure of formation fluid in a well.
15b, Usolskaya Street, Perm, Russia 
