Hydraulic actuation system for diverless bell mouth
The present invention proposes a device capable of allowing remote unlocking operation and remaining compatible with the possibility of a mechanical and manual drive. The device is a hydraulic actuator ( 2 ) with hydraulic power supply through the lines coming from the platform. It also has a handle ( 4 ) for manual driving. The invention allows cost reduction with PLSVs (waiting for diving and standby weather) and with diving activities themselves, in addition to greater agility in pull-out operations. Further, it promotes the diminishment of the need for diving and, consequently, lower MHRE (Man-Hour of risk exposure).
1 . A diverless bell mouth system comprising:
a body defining a central passage to receive and release a helmet of a bend stiffener;
a hydraulic actuation system arranged and configured to conduct pull-out operations with the helmet of the bend stiffener without use of a diver or a ROV, wherein the hydraulic actuation system comprises at least one single-acting, spring-return hydraulic actuator that is remotely activated, the at least one single-acting, spring-return hydraulic actuator comprises a hydraulic inlet and outlet, a piston, a first rod having a first diameter, and a second rod having a second diameter larger than the first diameter, and the hydraulic inlet and outlet are connected in the same line so that the piston moves by difference in areas between the first rod and the second rod; and
locking pawls configured to be actuated by the at least one single-acting, spring-return hydraulic actuator between a spring-loaded locking position for pull-in operations and a hydraulically driven retracted position for pull-out operations, wherein the locking pawls transfer a load from the helmet to the body when in the locking position.
2 . The diverless bell mouth system of claim 1 , wherein the body has one of the following three sizes: 32″ for umbilicals, or 46″ or 48″ for flexible risers for production, service, and injection of gas or water.
3 . The diverless bell mouth system of claim 1 , wherein the hydraulic actuation system comprises one of the at least one single-acting, spring-return hydraulic actuator for each locking pawl.
4 . The diverless bell mouth system of claim 1 , wherein the hydraulic actuation system has hydraulic power supplied by lines coming from a platform, the lines arranged to drive the hydraulic actuation system and the locking pawls between the locking position and the retracted position.
5 . The diverless bell mouth system of claim 4 , wherein the hydraulic actuation system comprises:
one of the at least one single-acting, spring-return hydraulic actuator coupled to each locking pawl, each single-acting, spring-return hydraulic actuator arranged to move in unison with the locking pawl each single-acting, spring-return hydraulic actuator is coupled to, and each single-acting, spring return hydraulic actuator comprising a cylinder defining the hydraulic inlet and outlet.
6 . The diverless bell mouth system of claim 1 , wherein the hydraulic actuation system comprises a hydraulic power unit located remotely from the body.