A method of adapting a downhole multi-phase twin screw pump (10) for use
in wells having a high gas content. A first step involves positioning a
supplementary liquid channel (22,122) in a housing (12) of the pump in
fluid communication with a pumping screw near an intake end (14) of the
pump. A second step involves feeding supplementary liquid through the
supplementary liquid channel to the pumping screw, thereby enhancing a
liquid seal around the pumping screw.