Apparatus for detecting leaks in a fluid delivery line

Claim 3

In an apparatus for detecting leakage in excess of a preselected leakage rate from a fluid delivery line through which fluid is intermittently delivered under pressure and wherein the pressure in the line can vary over a wide range between a low pressure and a relatively higher delivery pressure, said apparatus comprising, a casing having a main inlet chamber and a main outlet chamber adapted to pass fluid therethrough to the delivery line and a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber to apply fluid pressure to said main pressure responsive member for holding said main valve member in its closed position, pressure responsive control means operative when the main valve member is in its closed position and the pressure in the main outlet chamber is below a preselected intermediate pressure range for passing fluid at a preselected signal rate from the main inlet to the main outlet to allow the pressure in said main outlet chamber to rapidly build up to said preselected intermediate pressure range, said pressure responsive control means including means operative when the pressure in said main outlet chamber reaches said preselected intermediate pressure range to restrict flow from said main inlet to said main outlet to said preselected leakage rate, said pressure responsive control means including means operative when the pressure in the main outlet chamber rises above said intermediate pressure range to pass fluid from said main pressure chamber to said main outlet chamber at a rate greater than the rate of flow of fluid through said control passage means into said main pressure chamber to thereby substantially equalize pressures on opposite sides of said pressure responsive member and allow said main valve member to open.

Claim 4

In an apparatus for detecting leakage in excess of a preselected leakage rate from a fluid delivery line through which fluid is intermittently delivered under pressure and wherein the pressure in the line can vary over a wide range between a low pressure and a relatively higher delivery pressure, said apparatus comprising, a casing having a main inlet chamber and a main outlet chamber adapted to pass fluid therethrough to the delivery line and a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber to apply fluid pressure to said main pressure responsive member for holding said main valve member in its closed position, pressure responsive control means operative when the main valve member is in its closed position and the pressure in the main outlet chamber is below a preselected intermediate pressure range for passing fluid at a preselected signal rate from the main inlet to the main outlet to allow the pressure in said main outlet chamber to rapidly build up to said preselected intermediate pressure range, said pressure responsive control means including means operative when the pressure in said main outlet chamber reaches said preselected intermediate pressure range to restrict flow from said main inlet to said main outlet to said preselected leakage rate, said pressure responsive control means including means operative when the pressure in the main outlet chamber rises above said intermediate pressure range to pass fluid from said main pressure chamber to said main outlet chamber at a rate greater than the rate of flow of fluid through said control passage means into said main pressure chamber to thereby substantially equalize pressures on opposite sides of said pressure responsive member and allow said main valve member to open.

Claim 5

In an apparatus for detecting leakage in excess of a preselected leakage rate from a fluid delivery line through which fluid is intermittently delivered under pressure and wherein the pressure in the line can vary over a wide range between a low pressure and a relatively higher delivery pressure, said apparatus comprising, a casing having a main inlet chamber and a main outlet chamber adapted to pass fluid therethrough to the delivery line and a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber and dimensioned to pass fluid to the main pressure chamber at a rate in excess of a preselected signal rate, a leak detector pilot valve including a pilot valve casing having a pilot inlet communicating with said main pressure chamber and a pilot outlet communicating with said main outlet chamber, pressure operated pilot valve means controlling flow between said pilot inlet and said pilot outlet operative when the pressure in said main outlet chamber is below a preselected intermediate pressure range to pass fluid at said preselected signal rate from said main pressure chamber to said main outlet chamber, said pressure operated pilot valve means being operative when the pressure in said main outlet chamber reaches said intermediate pressure range to restrict flow between the pilot inlet and the pilot outlet to said preselected leakage rate, said pressure operated pilot valve means being operative when the pressure in said main outlet chamber rises above said preselected intermediate pressure range to open and pass fluid from the main pressure chamber at a rate greater than the rate of fluid flow through said control passage to thereby allow said main valve member to open.

Claim 6

In an apparatus for detecting leakage in excess of a preselected leakage rate from a fluid delivery line through which fluid is intermittently delivered under pressure and wherein the pressure in the line can vary over a wide range between a low pressure and a relatively higher delivery pressure, said apparatus comprising, a casing having a main inlet chamber and a main outlet chamber adapted to pass fluid therethrough to the delivery line and a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber and dimensioned to pass fluid to the main pressure chamber at a rate in excess of a preselected signal rate, a leak detector pilot valve including a pilot valve casing having a pilot inlet communicating with said main pressure chamber and a pilot outlet communicating with said main outlet chamber, pressure operated pilot valve means controlling flow between said pilot inlet and said pilot outlet operative when the pressure in said main outlet chamber is below a preselected intermediate pressure range to pass fluid at said preselected signal rate from said main pressure chamber to said main outlet chamber, said pressure operated pilot valve means being operative when the pressure in said main outlet chamber reaches said intermediate pressure range to restrict flow between the pilot inlet and the pilot outlet to said preselected leakage rate, said pressure operated pilot valve means being operative when the pressure in said main outlet chamber rises above said preselected intermediate pressure range to open and pass fluid from the main pressure chamber at a rate greater than the rate of fluid flow through said control passage to thereby allow said main valve member to open.

Claim 7

An apparatus according to claim 3 including means defining a second chamber at said other side of the pressure responsive member, nd means providing restricted communication between said second chamber and said main outlet chamber to inhibit rapid movement of said main pressure responsive member and main valve member.

Claim 8

An apparatus according to claim 3 wherein said main valve member has means cooperating with said main valve seat to provide a sliding seal therebetween during initial movement of the main valve member relative to the main valve seat.

Claim 9

In an apparatus for detecting leakage in excess of a preselected leakage rate from a fluid delivery line through which fluid is intermittently delivered under pressure and wherein the pressure in the line can vary oveR a wide range between a low pressure and a relatively higher delivery pressure, said apparatus comprising, a casing having a main inlet chamber and a main outlet chamber adapted to pass fluid therethrough to the delivery line and a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber and dimensioned to pass fluid to the main pressure chamber at a rate in excess of said preselected leakage rate, a leak detector pilot valve including a pilot valve casing having a pilot inlet communicating with said main pressure chamber and a pilot outlet communicating with said main outlet chamber, pilot valve means controlling flow from said pilot inlet to said pilot outlet, means responsive to the pressure in said main outlet chamber for positioning said pilot valve means in an initial position when the pressure in said main outlet passage is below a preselected intermediate pressure range between said low pressure and said delivery pressure, said pressure responsive means being operative to move said valve means to an intermediate position when the pressure in said main outlet passage is in said intermediate range and to an open position when the pressure in the main outlet passage is above said intermediate range, said pilot valve means being operative in said initial position to define an initial flow passage between said pilot inlet and pilot outlet that is smaller than control passage means to pass fluid at a rate in excess of said preselected leakage rate to said main outlet chamber to rapidly fill the delivery line, said pilot valve means including means operative when the pilot valve means is in said intermediate position to define an intermediate flow passage between said pilot inlet and pilot outlet which is smaller than said initial flow passage to pass fluid at said preselected leakage rate to said main outlet chamber to increase the pressure in said main outlet chamber if the leakage from the delivery line is less than said preselected leakage rate, said pilot valve means including means operative in said open position to define a flow passage between said pilot inlet and pilot outlet which is larger than said control passage to substantially equalize the pressure in said main pressure chamber with the pressure in said main outlet chamber.

Claim 10

In an apparatus for detecting leakage in excess of a preselected leakage rate from a fluid delivery line through which fluid is intermittently delivered under pressure and wherein the pressure in the line can vary oveR a wide range between a low pressure and a relatively higher delivery pressure, said apparatus comprising, a casing having a main inlet chamber and a main outlet chamber adapted to pass fluid therethrough to the delivery line and a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber and dimensioned to pass fluid to the main pressure chamber at a rate in excess of said preselected leakage rate, a leak detector pilot valve including a pilot valve casing having a pilot inlet communicating with said main pressure chamber and a pilot outlet communicating with said main outlet chamber, pilot valve means controlling flow from said pilot inlet to said pilot outlet, means responsive to the pressure in said main outlet chamber for positioning said pilot valve means in an initial position when the pressure in said main outlet passage is below a preselected intermediate pressure range between said low pressure and said delivery pressure, said pressure responsive means being operative to move said valve means to an intermediate position when the pressure in said main outlet passage is in said intermediate range and to an open position when the pressure in the main outlet passage is above said intermediate range, said pilot valve means being operative in said initial position to define an initial flow passage between said pilot inlet and pilot outlet that is smaller than control passage means to pass fluid at a rate in excess of said preselected leakage rate to said main outlet chamber to rapidly fill the delivery line, said pilot valve means including means operative when the pilot valve means is in said intermediate position to define an intermediate flow passage between said pilot inlet and pilot outlet which is smaller than said initial flow passage to pass fluid at said preselected leakage rate to said main outlet chamber to increase the pressure in said main outlet chamber if the leakage from the delivery line is less than said preselected leakage rate, said pilot valve means including means operative in said open position to define a flow passage between said pilot inlet and pilot outlet which is larger than said control passage to substantially equalize the pressure in said main pressure chamber with the pressure in said main outlet chamber.

Claim 11

An apparatus according to claim 6 wherein said control passage comprises a passage formed in said means connecting said main pressure responsive member to said main valve member.

Claim 12

An apparatus according to claim 6 including means defining a second chamber at said other side of said main pressure responsive member, and means providing restricted communication between said second chamber and said main outlet chamber to inhibit rapid movement of said main pressure responsive member and said main valve member.

Claim 13

An apparatus according to claim 8 wherein said main valve member has means cooperating with said main valve seat to provide a sliding seal therebetween during initial movement of said main valve member relative to said seat.

Claim 14

An apparatus according to claim 6 wherein said main valve member has means cooperating with said main valve seat to provide a sliding seal therebetween during initial movement of said main valve member relative to said seat.

Claim 15

In a pumping system including a delivery line, a flow control valve means at oNe end of the line for controlling flow therefrom, pump means communicating with the other end of the delivery line operable to intermittently deliver fluid under pressure to the line whereby the pressure in the line can vary from full pump delivery pressure when the pump is operating and the flow control valve means is closed to a relatively low pressure when the pump is stopped, means for detecting leakage in excess of a preselected leakage rate from the delivery line comprising a casing having a main inlet chamber communicating with the outlet of the pump and a main outlet chamber communicating with the delivery line to pass fluid thereto, a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber and dimensioned to pass fluid to the main pressure chamber at a rate in excess of said preselected leakage rate, a leak detector pilot valve including a pilot valve casing having a pilot inlet communicating with said main pressure chamber and a pilot outlet communicating with said main outlet chamber, pilot valve means controlling flow from said pilot inlet to said pilot outlet, means responsive to the pressure in said main outlet chamber for positioning said pilot valve means in an initial position when the pressure in said main outlet passage is below a preselected intermediate pressure range between said low pressure and said delivery pressure, said pressure responsive means being operative to move said valve means to an intermediate position when the pressure in said main outlet passage is in said intermediate range and to an open position when the pressure in the main outlet passage is above said intermediate range, said pilot valve means being operative in said initial position to define an initial flow passage between said pilot inlet and pilot outlet that is smaller than control passage means to pass fluid at a rate in excess of said preselected leakage rate to said main outlet chamber to rapidly fill the delivery line, said pilot valve means including means operative when the pilot valve means is in said intermediate position to define an intermediate flow passage between said pilot inlet and pilot outlet which is smaller than said initial flow passage to pass fluid at said preselected leakage rate to said main outlet chamber to increase the pressure in said main outlet chamber if the leakage from the delivery line is less than said preselected leakage rate, said pilot valve means including means operative in said open position to define a flow passage between said pilot inlet and pilot outlet which is larger than said control passage to substantially equalize the pressure in said main pressure chamber with the pressure in said main outlet chamber.

Claim 16

In a pumping system including a delivery line, a flow control valve means at oNe end of the line for controlling flow therefrom, pump means communicating with the other end of the delivery line operable to intermittently deliver fluid under pressure to the line whereby the pressure in the line can vary from full pump delivery pressure when the pump is operating and the flow control valve means is closed to a relatively low pressure when the pump is stopped, means for detecting leakage in excess of a preselected leakage rate from the delivery line comprising a casing having a main inlet chamber communicating with the outlet of the pump and a main outlet chamber communicating with the delivery line to pass fluid thereto, a main valve seat intermediate said main inlet and main outlet chambers, a main valve member controlling flow through said main valve seat and mounted for movement in the direction of fluid flow through the valve to its open position, a main pressure chamber, and a main pressure responsive member having one side exposed to pressure in said main pressure chamber and the other side exposed to pressure in said main outlet chamber, means connecting said main pressure responsive member to said main valve member for moving the latter to a closed position in response to a preselected pressure differential between the main pressure chamber and the main outlet chamber, control passage means communicating said main outlet chamber with said main pressure chamber and dimensioned to pass fluid to the main pressure chamber at a rate in excess of said preselected leakage rate, a leak detector pilot valve including a pilot valve casing having a pilot inlet communicating with said main pressure chamber and a pilot outlet communicating with said main outlet chamber, pilot valve means controlling flow from said pilot inlet to said pilot outlet, means responsive to the pressure in said main outlet chamber for positioning said pilot valve means in an initial position when the pressure in said main outlet passage is below a preselected intermediate pressure range between said low pressure and said delivery pressure, said pressure responsive means being operative to move said valve means to an intermediate position when the pressure in said main outlet passage is in said intermediate range and to an open position when the pressure in the main outlet passage is above said intermediate range, said pilot valve means being operative in said initial position to define an initial flow passage between said pilot inlet and pilot outlet that is smaller than control passage means to pass fluid at a rate in excess of said preselected leakage rate to said main outlet chamber to rapidly fill the delivery line, said pilot valve means including means operative when the pilot valve means is in said intermediate position to define an intermediate flow passage between said pilot inlet and pilot outlet which is smaller than said initial flow passage to pass fluid at said preselected leakage rate to said main outlet chamber to increase the pressure in said main outlet chamber if the leakage from the delivery line is less than said preselected leakage rate, said pilot valve means including means operative in said open position to define a flow passage between said pilot inlet and pilot outlet which is larger than said control passage to substantially equalize the pressure in said main pressure chamber with the pressure in said main outlet chamber.