Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
277 words
A valve arrangement for automatically stopping the flow of a medium through a conduit section on the occurrence of a rupture or leak in the section, the arrangement comprising a closing or blocking valve including a movable closure means mounted at the inlet of the conduit section, said valve normally being open and offering the medium flowing therethrough a resistance resulting in a first pressure drop (Δp 1 ) across the valve is response to the size of the flow, said first pressure drop being arranged to actuate the closure means for closure thereof; and a flow sensing means mounted at the outlet of the conduit section, including, for example, an orifice plate or venturi constriction known per se, between the inlet and outlet sides of which the medium flowing therethrough generates a second pressure drop (Δp 2 ) in response to the size of the flow, this second pressure drop being arranged to actuate the said closure means in the opposite direction to that of closure, the improvement wherein the closure means includes two parts, each movable in relation to the other and actuated by the said pressure drops (Δp 1 , Δp 2 ), the first part consisting of a blocking body arranged for moving towards the closure position by the first pressure drop (Δp 1 ) across the blocking valve for blocking the flow through the valve when in said closure position, while the second part consists of a servo body arranged for actuation by the second pressure drop (Δp 2 ) across the flow sensing means to thereby in turn act on the blocking body to counteract its movement towards the closure position.
Claim 2
Dependent Claim
277 words
A valve arrangement for automatically stopping the flow of a medium through a conduit section on the occurrence of a rupture or leak in the section, the arrangement comprising a closing or blocking valve including a movable closure means mounted at the inlet of the conduit section, said valve normally being open and offering the medium flowing therethrough a resistance resulting in a first pressure drop (Δp 1 ) across the valve is response to the size of the flow, said first pressure drop being arranged to actuate the closure means for closure thereof; and a flow sensing means mounted at the outlet of the conduit section, including, for example, an orifice plate or venturi constriction known per se, between the inlet and outlet sides of which the medium flowing therethrough generates a second pressure drop (Δp 2 ) in response to the size of the flow, this second pressure drop being arranged to actuate the said closure means in the opposite direction to that of closure, the improvement wherein the closure means includes two parts, each movable in relation to the other and actuated by the said pressure drops (Δp 1 , Δp 2 ), the first part consisting of a blocking body arranged for moving towards the closure position by the first pressure drop (Δp 1 ) across the blocking valve for blocking the flow through the valve when in said closure position, while the second part consists of a servo body arranged for actuation by the second pressure drop (Δp 2 ) across the flow sensing means to thereby in turn act on the blocking body to counteract its movement towards the closure position.
Claim 3
Dependent Claim
91 words
A valve arrangement as claimed in claim 1, in which the blocking body of the closure means coacts with a valve seat in the blocking valve to assume its closure position, the improvement wherein the blocking body, when there is a flow through the conduit section in the opposite direction, i.e. from the outlet of the section to its inlet, is arranged to be lifted up by the flowing medium from the valve seat independent of the coacting servo body, to allow free flow through the blocking valve in this direction.
Claim 4
Dependent Claim
117 words
A valve arrangement as claimed in claim 2, wherein the blocking body of the closure means consists of a valve ball coacting with the valve seat, the ball being kept lifted out of the seat with the aid of a thrust means to allow normal flow through the valve from the inlet to the outlet of the conduit section, whereby the servo body is slidably accommodated in a chamber which is separated by the body into two parts in communication respectively with the inlet side and outlet side of the flow sensing means so that the second pressure drop (Δp 2 ) across the flow sensing means actuates the servo body for keeping the valve ball raised.
Claim 5
Dependent Claim
38 words
A valve arrangement as claimed in claim 3, wherein the said servo body consists of a second valve ball coacting through the intermediary of a movable pushrod or pin with the first-mentioned valve ball forming the blocking body.
Claim 6
Dependent Claim
73 words
A valve arrangement as claimed in claim 1, wherein the flow sensing means comprises a movable platelike member having a constriction orifice were the said second pressure drop (Δp 2 ) is generated when the medium flows from the inlet to the outlet of the conduit section, the platelike member being also arranged to uncover an opening offering considerably less flow resistance than said constriction orifice when the medium flows in the oppositedirection.
Claim 7
Dependent Claim
57 words
A valve arrangement as claimed in claim 1, wherein the second pressure drop (Δp 2 ) across the flow sensing means for actuating the servo body of the closure means is transferred by a pilot line comprising dual hoses, each hose communicating with one side of the sensing means, the hoses being arranged one inside the other.