sealing ring 230 the piston pump 260 is driven by an eccentric diameter cam 262 formed in the drive shaft 220 and is disposed to provide pressurized fluid from a fluid reservoir 272 to the pump 260 through passageway 265 and on to the interface between the mating 220 and sealing 230 rings via passageway 264 the piston pump 260 includes a dynamic seal 263 with the drive shaft 220 to prevent pressure loss in the pressurized fluid i e to separate the high and lower pressure fluid the tool 200 may optionally include a bladder 275 e g an elastomeric boot disposed in the fluid reservoir 272 for providing pressure equalization between drilling fluid in annular region 215 and lubricating fluid in the fluid reservoir 272 use of the bladder 275 advantageously tends to equalize pressure spikes between the drilling fluid and sealed fluid and therefore tends to reduce the likelihood of pressure reversals at the interface between the mating 220 and sealing 230 rings as described above the exemplary embodiments shown on fig2 and 4 include pumps 60 and 260 deployed locally with the sealing members in the embodiment shown on fig2 the pump 60 is deployed integrally with the sealing ring carrier 35 in the exemplary embodiment shown on fig4 pump 260 is deployed in close proximity to mating 220 and sealing 230 rings in this exemplary embodiment pump 260 is deployed about 6 inches above the mating 220 and sealing 230 rings of course the invention is not limited.