A decompression heat-insulating pipe structure that can exhibit the desired heat-insulating performance and is easy to assemble. In the structure, a space between ends of inner and outer tubes is decompressed. The outer tube includes a first flange, which extends radially inward from an axially one end thereof, and a second flange, which extends radially outward from the axially other end thereof. The inner tube includes a third flange, which extends radially inward from an axially one end thereof and is opposed to the first flange at an axially inward position of the first flange, and a fourth flange, which extends radially outward from the axially other end thereof and being opposed to the second flange at an axially outward position of the second flange. First and second elastic seal members are disposed between the first and third flanges and between the second and fourth flanges, respectively.

A decompression heat-insulating pipe structure that can exhibit the desired heat-insulating performance and is easy to assemble. In the structure, a space between ends of inner and outer tubes is decompressed. The outer tube includes a first flange, which extends radially inward from an axially one end thereof, and a second flange, which extends radially outward from the axially other end thereof. The inner tube includes a third flange, which extends radially inward from an axially one end thereof and is opposed to the first flange at an axially inward position of the first flange, and a fourth flange, which extends radially outward from the axially other end thereof and being opposed to the second flange at an axially outward position of the second flange. First and second elastic seal members are disposed between the first and third flanges and between the second and fourth flanges, respectively.

A sealing system including a first end and a second end with flexible bellows extending therebetween. The first end includes a base plate with an inner ring having an inner diameter. The inner ring is configured to receive a pipe therethrough. The pipe has an outer diameter, which is smaller than the inner diameter of the inner ring. The bellows of the sealing system has a first length in a first position and second length in a second position. Upon axial expansion of the pipe, the bellows is configured to move from the first position to the second position. The sealing system may also comprise a mechanical protective element, such as a shroud which extends around the bellows. Movement of the bellows can be further limited with rods extending from the shroud to a surrounding substrate or a cable fixing a maximum distance between the pipe and the shroud.

A transfer tube assembly comprises a transfer tube slidably engaged in sealing engagement with a first component. The transfer tube has a shoulder engageable with a stopper for limiting relative axial movement between the transfer tube and the first component. The shoulder has an abutment surface facing a corresponding bore surface of the first bore of the first component. The abutment surface and the bore surface are configured to generate axially opposing reaction forces in response to the abutment surface and the bore surface contacting each other.

An extendable spool is disclosed. The length of the extendable spool is able to continuously varied. The extendable spool accounts for length variances in flow lines by extending the flow line rather than redirecting the flow. Because the flow direction does not make any turns, erosion is minimized on both the extendable spool and downstream parts. The extendable spool is readily scalable from small diameters to large diameters. Because of this, it requires fewer lines and therefore less setup time to account for length differences between large diameter lines.

A method of attenuating annular pressure buildup within a wellbore. The method includes accessing a wellbore, with the wellbore having an annulus disposed between first and second strings of casing. The method also includes placing a column of cement around the second string of casing generally below the first string of casing. The method further includes pumping a fluid mixture into the annulus, forming a fluid column. The fluid mixture comprises a carrier fluid, and a plurality of compressible particles dispersed in the carrier fluid. Each of the compressible particles is fabricated to partially collapse in response to thermal expansion of the fluid mixture. The method also includes placing a wellhead over the wellbore, thereby forming a trapped annulus in the wellbore. The method additionally includes at least partially sealing the annular region along at least one depth above the column of cement to inhibit vertical migration of the compressible particles.

A tubular structure includes at least one exterior tube and at least one interior tube, at least a portion of the interior tube is disposed within the exterior tube. The tubular structure further includes at least one expansion joint provided between the exterior tube and the interior tube and the expansion joint allows lateral expansion or contraction of the exterior tube and the interior tube and maintains a pressure within the exterior and the interior tubes.

A tubular structure includes at least one exterior tube and at least one interior tube, at least a portion of the interior tube is disposed within the exterior tube. The tubular structure further includes at least one expansion joint provided between the exterior tube and the interior tube and the expansion joint allows lateral expansion or contraction of the exterior tube and the interior tube and maintains a pressure within the exterior and the interior tubes.

Provided is an apparatus for removing thermal stratification generated by turbulent penetration by using a rotation of a pipe wall. The apparatus removes thermal stratification formed in a branch pipe branching from a main pipe through which a high-temperature fluid flows, the apparatus including: a connection body portion including a hollow first body and a hollow second body, the first body being coupled to one side of the branch pipe, and the second body being spaced apart from the first body and connected to other side of the branch pipe; and a hollow rotating part between the first body and the second body, the rotating part rotating around a center of the branch pipe.

A pressure balancing apparatus can have a compression collar to mate with a component comprising a seal, and a gripper to anchor to a tube and the compression collar. The compression collar is used to apply an axial force to the tube to relieve shear stress on proximate seals. The method can include mating a compression collar to a component comprising a seal, anchoring a gripper to a tube, mating the gripper to the compression collar, and using the compression collar to apply an axial force to the tube.