Patent ID: 8602053

Claim:
A device comprising part of a system for measuring differential pressures in a fluid system, the device comprising: a valve assembly ( 1 ) including a valve body ( 7 ) with an inlet ( 13 ) and an outlet ( 14 ) for connection to the fluid system, ducts ( 32 , 33 ) for facilitating communication with a differential pressure sensor ( 12 ) for measurement of the differential pressure, a cavity ( 22 ) communicating with the ducts ( 32 , 33 ) and the cavity ( 22 ) including a calibration spool ( 10 ) which is axially moveable, along the cavity ( 22 ), between a measure position and an axially spaced initial position for zero point calibration and flushing the valve assembly ( 1 ), and the calibration spool ( 10 ) separating the differential pressure sensor ( 12 ) from the fluid system when the calibration spool ( 10 ) is in the initial position, and the calibration spool ( 10 ) including sealing elements ( 27 ), which prevent fluid communication between the ducts ( 32 , 33 ) and the first cavity ( 22 ) when the calibration spool ( 10 ) is in the initial position, wherein a flushing function is obtained when the calibration spool ( 10 ) is spaced from the measuring position, the calibration spool ( 10 ) has a design that permits an open passage of flow between a high pressure side and a low pressure side, from the inlet ( 13 ), via a duct ( 21 ) between the inlet ( 13 ) and the cavity ( 22 ) in the valve body ( 7 ), to the cavity ( 22 ) in the valve body ( 7 ), through a cavity ( 26 ) in the calibration spool ( 10 ) and further to the cavity ( 22 ) in the valve body ( 7 ), thereafter to a duct ( 23 ) between the cavity ( 22 ) in the valve body ( 7 ) and the outlet ( 14 ) and thereafter to the outlet ( 14 ).