Device for inserting tubular members together

In a well, a lower tubular member having a sealing surface located in the well, an upper tubular member which inserts into engagement with the lower tubular member, the upper and lower tubular members being exposed to well fluid presssure in the well, an improved means for sliding the upper tubular member into engagement with the lower tubular member during running in, comprising in combination:

• the upper tubular member having a first side and a second side, the second side having a sealing section which mates with the sealing surface of the lower tubular member;
• a running tool having a tubular sidewall;
• a pair of axially spaced apart annular seals located on the running tool sidewall for sealingly engaging the first side of the upper tubular member above and below the sealing section during running in;
• the running tool sidewall and the first side of the upper tubular member having an annular recess between them during running in, the seals of the running tool being located above and below the recess during running in;
• the seals of the running tool defining a low pressure area in the recess between the running tool and the first side of the upper tubular member which is isolated from the hyrdostatic pressure of the well;
• the sealing section of the upper tubular member being exposed to well fluid pressure during running in, resulting in a pressure difference across the upper tubular member between the low pressure area and the well fluid pressure, the thickness of the upper tubular member between the first side and the sealing section being selected to be sufficiently thin so as to allow the sealing section to resiliently deflect radially toward the low pressure area due to the pressure difference, to reduce sliding contact of the sealing section with the sealing surface as the upper tubular member slides into engagement with the lower tubular member;
• and
• the running tool seals being movable upward relative to the upper tubular member after the upper tubular member has reached its engaged position with the lower tubular member, to equalize the pressure between the upper tubular member first side and sealing section, allowing the sealing section to move radially into engagement with the sealing surface.

In a well, a lower tubular member located in the well with an upper open end and a sealing surface, an upper tubular member which inserts into engagement with the lower tubular member, the lower tubular member and the upper tubular member being exposed to well fluid pressure, an improved means for sliding the upper tubular member into engagement with the lower tubular member during running in, comprising in combination:

• the upper tubular member having a first side and an second side, the second side having a sealing section with axially spaced apart metal sealing bands which mate with the sealing surface of the lower tubular member, each of the sealing bands having a diameter prior to insertion that has an interference fit with the sealing surface;
• a running tool having a tubular sidewall;
• a pair of annular seals located on the sidewall of the running tool and spaced apart a selected distance for sealingly engaging the first side of the upper tubular member above and below the sealing section during running in;
• the running tool sidewall having an annular recess located between the seals;
• the seals of the running tool defining a low pressure area in the recess between the running tool and the first side which is isolated from the fluid pressure of the well;
• the sealing section of the upper tubular member being exposed to well fluid pressure during running in, resulting in a pressure difference across the upper tubular member between the low pressure area and the well fluid pressure, the thickness of the upper tubular member between the first side and the sealing section being selected to be sufficiently thin so as to allow the sealing section to resiliently deflect radially into the recess due to the pressure difference enough to remove the intereference fit of the sealing section with the sealing surface as the upper tubular member slides into engagement with the lower tubular member;
• and
• means for moving the running tool seals upward relative to the upper tubular member after the upper tubular member has reached its engaged position with the lower tubular member, to equalize the pressure between the upper tubular member first side and sealing section, allowing the sealing section to move radially into engagement with the sealing surface.

A method for sliding an upper tubular member into engagement with a sealing surface of a lower tubular member in a well having well fluid pressure, comprising in combination:

• providing the upper tubular member with a first side and a second side and providing the second side with a sealing section for mating with the sealing surface of the lower tubular member:
• providing a running tool with a tubular sidewall;
• sealingly engaging the first side of the upper tubular member above and below the sealing section with the running tool to define a low pressure area;
• lowering the running tool and upper tubular member into the well;
• exposing the sealing section to well fluid pressure and isolating the low pressure area from well fluid pressure to provide a pressure differential between the low pressure area and the well fluid pressure;
• resiliently deflecting the sealing section radially toward the low pressure area due to the pressure differential, to reduce sliding contact of the sealing section with the sealing surface as the upper tubular member slides into engagement with the lower tubular member;
• then
• equalizing the pressure between the upper tubular member first side and sealing section, and allowing the sealing section to move radially into engagement with the sealing surface.

A method for sliding an upper tubular member into engagement with a sealing surface of a lower tubular member in a well having well fluid pressure, comprising in combination:

• providing the upper tubular member with a first side and a second side and providing the second side with a sealing section for mating with the sealing surface of the lower tubular member:
• providing a running tool with a tubular sidewall;
• sealingly engaging the first side of the upper tubular member above and below the sealing section with the running tool to define a low pressure area;
• lowering the running tool and upper tubular member into the well;
• exposing the sealing section to well fluid pressure and isolating the low pressure area from well fluid pressure to provide a pressure differential between the low pressure area and the well fluid pressure;
• resiliently deflecting the sealing section radially toward the low pressure area due to the pressure differential, to reduce sliding contact of the sealing section with the sealing surface as the upper tubular member slides into engagement with the lower tubular member;
• and
• moving the running tool seals upward relative to the upper tubular member after the upper tubular member has reached its engaged position with the lower tubular member, equalizing the pressure between the upper tubular member first side and sealing section, and allowing the sealing section to move radially into engagement with the sealing surface.