FLUID PRESSURE PULSE GENERATING APPARATUS WITH PRIMARY SEAL ASSEMBLY, BACK UP SEAL ASSEMBLY AND PRESSURE COMPENSATION DEVICE AND METHOD OF OPERATING SAME

摘要

The embodiments described herein generally relate to a fluid pressure pulse generating apparatus with a primary seal assembly (54), back up seal assembly (70) and pressure compensation device (48). The pressure compensation device comprises a membrane support and a longitudinally extending membrane system. The membrane support has a longitudinally extending bore therethrough for receiving a driveshaft of the fluid pressure pulse generating apparatus. The longitudinally extending membrane system comprising a longitudinally extending outer membrane sleeve and a longitudinally extending inner membrane sleeve with the inner membrane sleeve positioned inside the outer membrane sleeve. The membrane system is sealed to the membrane support to allow flexing of the membrane system in response to fluid pressure on either an inner longitudinal surface of the membrane system or an outer longitudinal surface of the membrane system and to prevent fluid on the inner longitudinal surface mixing with fluid on the outer longitudinal surface.