Tether connector for a tension leg platform

A foundation and tether assembly for a tension leg platform comprising:

• a foundation template secured to an ocean bottom location;
• a base latch element secured to said foundation template, said base latch element including:
• a load ring having a generally cylindrical inner surface, said load ring being so oriented that said cylindrical inner surface defines a generally vertical central axis;
• and
• a plurality of shear lugs secured to said load ring inner surface in a generally annular array, said shear lugs being laterally spaced one from another to define a vertical passage intermediate each adjacent pair of shear lugs;
• a substantially vertical tether adapted to be secured at its upper end to a tension leg platform hull, said tether having a tether latch element at its lower end, said tether latch element being secured within said base latch element, said tether latch element including:
• a main body sized to pass through said load ring;
• and
• a plurality of shear lugs secured to and projecting radially outward from said main body in an annular array generally concentric with said load ring central axis, said tether latch shear lugs being sized and positioned to pass through said base latch element vertical passages, so that said tether latch element can be lowered into said base latch element;
• first turning means for automatically rotating said tether latch element in response to axial movement of said tether latch element within said base latch element so as to cause said two sets of shear lugs to come into vertical alignment, whereby said connector can be latched by lowering said tether latch element into said base latch element and then raising said tether latch element to cause said two sets of shear lugs to come into shear abutment with one another, restraining said tether from further upward displacement;
• and
• second turning means for automatically rotating said tether latch element in response to axial movement of said tether latch element within said base latch element after said two sets of shear lugs have been in shear abutment with one another so as to cause said tether latch element shear lugs to return to alignment with said vertical channels, whereby said connector can be unlatched by lowering said tether latch element within said base latch element and then raising said tether latch element out of said base latch element.

A foundation and tether assembly for a tension leg platform, comprising:

• a base latch element fixedly secured to said foundation, said base latch element defining a generally cylindrical recess having a substantially vertical axis, said base latch element including a plurality of shear lugs arranged in an annular array projecting radially inward a distance into said cylindrical recess, said shear lugs being spaced apart to define vertical passages between adjacent shear lugs;
• and
• a tether latch element secured to the lower end of said tether, said tether latch element having a generally cylindrical main body with a tapered lower end, said main body being sized to pass through the region defined by the radially inner surface of said base latch shear lugs, said tether latch element having a plurality of shear lugs projecting radially outward from said main body, said tether latch element shear lugs being sized and positioned to pass through said base latch element vertical passages;
• said base latch and tether latch elements being provided with first turning means for automatically rotating said tether latch element in response to axially lowering said tether latch element into said base latch element, said rotation occurring about said vertical axis and being sufficient to place at least a portion of said tether latch element shear lugs in vertical alignment with said base latch element shear lugs, whereby in response to inserting said tether latch element into said base latch element and then lifting said tether latch element, said tether latch element shear lugs come into shear abutment with said base latch shear lugs, restraining further upward movement of said tether latch element;
• and
• second turning means for automatically rotating said tether latch in response to axial movement of said tether latch element within said base latch element after said two sets of shear lugs have been in shear abutment with one another, said rotation occurring about said vertical axis and being sufficient to return said tether latch element shear lugs to alignment with said vertical channels, whereby said connector can be unlatched by lowering said tether latch element and then raising said tether latch element out of said base latch element.