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Developed for applications with space and stack-up height limitations, Trendsetter’s External Tree Cap (ETC) offers our customers a robust metal sealing cap for 27” OD H4 wellheads and mandrels in a lightweight, compact package.  While the ETC has been designed for challenging enviroments such as mud-line cellars with minimum depth requirements for assets below the mudline, it can be deployed in any situation where a simple, effective metal sealing cap is required.

The ETC is operated hydraulically using a hotstab from ROV or surface downline.  The H4 locking dogs are held in place with an actuating piston utilizing a flat-to-flat design which functions as the primary locking mechanism.  A secondary mechanical lock mechanism, actuated on the ROV panel, provides redundancy.  The unlock function is also operated hydraulically.  In the event a hydraulic unlock is not effected, mechanical secondary unlock rods can be engaged with an external tool to effect a positive release.

The ETC provides two bore penetrations, accessible by ROV hotstab, to facilitate pressure testing, fluid circulation, and venting of the well bore.  A hydrate inhibitor injection wash port is also accessible on the ROV panel.  An 18-3/4” VX profile gasket provides the metal seal to the wellbore.  The bore penetrations are fitted with metal sealing rotary gate valves and pressure retaining blind hotstabs.