US 12,006,776 B2
Installation of subsea risers
Andre Ramiro Amorim, Rio de Janeiro (BR); Davi Couto Neves Junior, Niteroi (BR); Alberto Lima Dos Santos, Niteroi (BR); and Mauricio Suarez de Oliveira, Rio de Janeiro (BR)
Assigned to SUBSEA 7 DO BRASIL SERVICOS LTDA, Niterói (BR)
Appl. No. 17/604,291
Filed by Subsea 7 do Brasil Servicos Ltda, Niteroi (BR)
PCT Filed Apr. 15, 2020, PCT No. PCT/BR2020/050130
§ 371(c)(1), (2) Date Oct. 15, 2021,
PCT Pub. No. WO2020/210887, PCT Pub. Date Oct. 22, 2020.
Claims priority of application No. 1905382 (GB), filed on Apr. 16, 2019.
Prior Publication US 2022/0195809 A1, Jun. 23, 2022
Int. Cl. E21B 17/01 (2006.01); B63B 35/03 (2006.01); E21B 19/00 (2006.01); E21B 43/01 (2006.01)
CPC E21B 17/012 (2013.01) [B63B 35/03 (2013.01); E21B 17/015 (2013.01); E21B 19/004 (2013.01); E21B 43/0107 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of installing a wave-configuration subsea riser, the method comprising:
suspending the riser from an installation vessel;
suspending an elongate clump weight in a catenary shape comprising first and second limbs extending upwardly from a conjoining bottom portion, with an upper end of the first limb, at a distal end of the clump weight, being attached to the riser and an upper end of the second limb, at a proximal end of the clump weight, being suspended from a winch or crane of the installation vessel; and
while lowering the riser progressively into the sea from the installation vessel, controlling a weight load applied by the clump weight to the riser by adjusting relative lengths of the first and second limbs of the clump weight;
the method further comprising attaching buoyancy modules to a hogbend portion of the riser aboard the installation vessel.