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The design of the DXe connector removes bolts from the load path, reducing wear, extending field life, and improving operational safety.

Source: Dril-Quip high-fatigue DXe pro?le and the H4 pro?le. The design re- a longer ?eld life than was originally anticipated. Fatigue per- moves bolts from the load path, so the connector experiences formance under these challenging conditions is crucial to con- loads only when latched and unlatched from the wellhead. tinued, safe operations, and that means test criteria must re?ect

The novel connector design features a locking wellhead pro- current harsh environments and anticipated future conditions.

?le with a self-aligning, slim gasket and can be used as a BOP, Believing it is only a matter of time before API TR7 becomes a subsea tree, or riser tieback connector. requirement for connectors, the team made the determination to test the DXe connector to API 17TR7 as well as API 16A stan- dards. Both standards require validation testing and con?rmation

TESTING THE MERIT OF THE DESIGN of design margins for normal, extreme, and survival capacities.

The locking pro?le is the primary mechanical interface be-

The connector was tested as a full-scale assembly at normal, tween the hydraulic connector and associated mandrel. Many hydraulic connectors in use today were designed for much less extreme, and survival ratings based on as-tested material prop- erties. Each test series included exposure to internal pressures severe environments and shallower water depths; however, pres- ent work environments generally expose connectors to higher from 0 psi to 20,000 psi working pressure of the connector in pressures and temperatures and greater static and cyclic loads. intervals of 5,000 psi, along with axial loads of +(-) 1MM lbf

Meanwhile, the systems are expected to perform consistently for of tension. The DXe connector went beyond the 13MM ft-lb january/february 2021 OFFSHORE ENGINEER 35