Apparatus for controlling the inflow of production fluids from a subterranean well

Abstract

A fluid flow control apparatus ( 100 ) for controlling the inflow of production fluids from a subterranean well includes a fluid discriminator section ( 104 ) and a flow restrictor section ( 106 ) that is configured in series with the fluid discriminator section ( 104 ) such that fluid must pass through the fluid discriminator section ( 104 ) prior to passing through the flow restrictor section ( 106 ). The fluid discriminator section ( 104 ) is operable to autonomously restrict at least a portion of an undesired fluid type, such as water or gas, from the production fluids. The flow restrictor section ( 106 ) is operable to restrict the flow rate of the production fluids, thereby minimizing the pressure drop across the fluid discriminator section ( 104 ).

1 . A flow control apparatus for controlling the inflow of production fluids from a subterranean well, the flow control apparatus comprising:
 a fluid discriminator section;   a flow restrictor section configured in series with the fluid discriminator section such that fluid must pass through the fluid discriminator section prior to passing through the flow restrictor section;   wherein the fluid discriminator section is operable to autonomously restrict at least a portion of an undesired fluid type from the production fluids; and   wherein the flow restrictor section is operable to restrict the flow rate of the production fluids.   
   
   
       2 . The flow control apparatus as recited in  claim 1  wherein the fluid discriminator section includes a substantially circumferential chamber having a plurality of circumferentially distributed outlets and a plurality of blocking members disposed within the substantially circumferential chamber. 
   
   
       3 . The flow control apparatus as recited in  claim 2  wherein at least a portion of the blocking members have a density greater than that of oil. 
   
   
       4 . The flow control apparatus as recited in  claim 2  wherein at least a portion of the blocking members have a density less than that of oil. 
   
   
       5 . The flow control apparatus as recited in  claim 2  wherein a first portion of the blocking members have a density greater than that of oil and wherein a second portion of the blocking members have a density less than that of oil. 
   
   
       6 . The flow control apparatus as recited in  claim 2  wherein a first portion of the blocking members have a weight that is greater than that of a second portion of the blocking members. 
   
   
       7 . The flow control apparatus as recited in  claim 2  further comprising spacer members disposed between at least some of the blocking members. 
   
   
       8 . The flow control apparatus as recited in  claim 2  wherein the blocking members are one of spherically shaped, cylindrically shaped and partially circumferentially shaped. 
   
   
       9 . The flow control apparatus as recited in  claim 1  wherein the flow restrictor section further comprises a passageway. 
   
   
       10 . The flow control apparatus as recited in  claim 9  wherein the passageway has an effective flow area less than about twenty five percent of an unrestricted effective flow area of the fluid discriminator section. 
   
   
       11 . The flow control apparatus as recited in  claim 9  wherein the passageway has an effective flow area less than about ten percent of an unrestricted effective flow area of the fluid discriminator section. 
   
   
       12 . The flow control apparatus as recited in  claim 9  wherein the passageway further comprises a helical passageway. 
   
   
       13 . The flow control apparatus as recited in  claim 9  wherein the passageway further comprises a plurality of helical passageways. 
   
   
       14 . A flow control apparatus for controlling the inflow of production fluids from a subterranean well, the flow control apparatus comprising:
 a sand control screen element;   a fluid discriminator section configured in series with the sand control screen element such that fluid must pass through the sand control screen element prior to passing through the fluid discriminator section;   a flow restrictor section configured in series with the fluid discriminator section such that fluid must pass through the fluid discriminator section prior to passing through the flow restrictor section;   wherein the fluid discriminator section is operable to autonomously restrict at least a portion of an undesired fluid type from the production fluids; and   wherein the flow restrictor section is operable to restrict the flow rate of the production fluids.   
   
   
       15 . The flow control apparatus as recited in  claim 14  wherein the fluid discriminator section includes a substantially circumferential chamber having a plurality of circumferentially distributed outlets and a plurality of blocking members disposed within the substantially circumferential chamber that cooperate with the outlets to autonomously restrict the at least a portion of the undesired fluid type from the production fluids. 
   
   
       16 . The flow control apparatus as recited in  claim 14  wherein a first portion of the blocking members have a density greater than that of oil and wherein a second portion of the blocking members have a density less than that of oil. 
   
   
       17 . The flow control apparatus as recited in  claim 14  wherein the flow restrictor section further comprises a passageway having an effective flow area less than twenty five about percent of an unrestricted effective flow area of the fluid discriminator section. 
   
   
       18 . The flow control apparatus as recited in  claim 14  wherein the flow restrictor section further comprises a helical passageway. 
   
   
       19 . A flow control apparatus for controlling the inflow of production fluids from a subterranean well, the flow control apparatus comprising:
 a fluid discriminator section;   a flow restrictor section configured in series with the fluid discriminator section such that fluid must pass through the fluid discriminator section prior to passing through the flow restrictor section;   wherein the fluid discriminator section includes a substantially circumferential chamber having a plurality of circumferentially distributed outlets and a plurality of blocking members disposed within the substantially circumferential chamber that cooperate with the outlets to autonomously restrict at least a portion of an undesired fluid type from the production fluids; and   wherein the flow restrictor section includes a helical passageway having an effective flow area less than twenty five about percent of an unrestricted effective flow area of the fluid discriminator section such that the flow restrictor section is operable to restrict the flow rate of the production fluids.   
   
   
       20 . The flow control apparatus as recited in  claim 19  wherein a first portion of the blocking members have a density greater than that of oil and wherein a second portion of the blocking members have a density less than that of oil.