ConocoPhillips
MANAGEMENT OF SUBSEA WELLHEAD STRESSES

Abstract:

The invention relates to a method and system for monitoring strain data on a subsea wellhead and associated tubing especially during a drilling or completion operation when the wellhead is connected via a riser to a drilling rig. The bending stresses on the wellhead assembly can be modelled and monitored, based on strain data from strain gauges attached to the conductor, surface casing and possibly also inner tubing. The strain gauges are located where maximum bending stresses occur, at around seafloor level. Data from the strain gauges is transmitted by radio to a receiver unit on the template, from which it may either be transmitted to the surface or stored and retrieved by divers or subsea vehicles.