In subsea offshore well operations, a subsea installation may include hydraulically and also electrically controlled equipment, such as valves which are remotely operated from a platform structure located at the surface of the ocean. Hydraulic and electrical control lines extending from the platform to the subsea installation are desired to be releasably connected to the subsea installation so that if the platform must move to another location or be released from its connection to the subsea station, such release may be readily made. In some instances, such a control line has been associated with tension line means integral therewith so that the line, sometimes called an umbilical line, may be locked at its lower end to the subsea installation.
An example of such an umbilical line construction is shown in my copending application Ser. No. 771,799 owned by a common assignee wherein the umbilical line extends from the subsea installation to a buoyant structure located about 300 feet below the sea surface and the umbilical line continues above the buoyant structure to a floating platform. The buoyant structure is connected with a marine riser system having a lower riser portion and an upper riser portion so that the upper riser portion and the upper portion of the umbilical line can be disconnected at the buoyant structure and the floating platform moved to another location upon such disengagement. The buoyant structure and the lower riser portion are free-standing to permit reengagement of the upper riser portion at a later time. It is desirable that the buoyant structure be securely tethered to the subsea installation so that in the event the lower riser portion should break, the buoyant structure, which exerts an upward tension on the lower riser portion, will not be suddenly released and rapidly travel to the surface and perhaps strike and cause damage to the floating platform normally thereabove.
In prior proposed locking systems for guide line connectors for use in such installations, manually operated locking devices were maintained in locked position by mechanical springs and were unlocked by use of a submarine or by use of go devil means.