Patent ID: 7107822

Claim:
An apparatus for on-line detection of leaky valve seals, said apparatus comprising: an isolation valve, wherein said isolation valve comprises at least one upstream seal, at least one downstream seal, a fluid flow diverter, and an inner cavity isolated from a fluid flow path by said at least one upstream seal and said at least one downstream seal; a vent port disposed in fluid communication with said inner cavity; a vent valve disposed in fluid communication with said vent port; and a differential pressure sensor disposed in fluid communication with each of said vent port and said fluid flow path; wherein said fluid flow diverter is used to divert at least some of said fluid flow into said inner cavity when said fluid flow diverter is at least partially opened, and to isolate fluid flow accumulated in said inner cavity when said fluid flow diverter is again closed, thereby allowing said fluid flow to accumulate in said inner cavity and said vent port; wherein said vent valve is used to evacuate fluid flow accumulated in said inner cavity and said vent port when said vent valve is opened, and again isolate fluid flow accumulating in said inner cavity when said vent valve is closed; and wherein said differential pressure sensor is used to determine whether either of said upstream seal and said downstream seal are leaking by measuring a difference between the pressure of fluid flow re-accumulating in said vent port and the pressure of fluid flow that has already passed said downstream seal and entered a downstream flow path.