Patent ID: 6139644
Filing Date: 2000-10-31
Classification: E21B,F16L,Y10T

Abstract:
Equipment for launching pigs into an undersea pipe of an undersea hydrocarbon flow line system, comprising:a first length of pipe connected at one end thereof to a first gas injection flow line and connected at another end thereof to a second U-shaped length of pipe which is in turn connected to a production flow line having a first check valve located near to a point of connection of said production flow line to a wellhead;a clear flow shut-off valve located in said first pipe length at a region close to and in front of the connection between said first pipe length and said second U-shaped pipe length; andfirst and second branches which connect said first pipe length to a second gas injection line connected at one end thereof to an annulus of a well, said first and second branches having means for preventing passage of a pig thereinto;wherein said first and second branches connecting said first pipe length to said second gas injection line from a section in said first pipe length, between the point of connection of said first and second branches to said first pipe length, in which a pig becomes immobilized when launched into said section.