Wickers with trapped fluid recesses for wellhead assembly

A wellhead assembly, comprising:

• a wellhead housing having a bore with a wellhead housing sidewall and a longitudinal axis;
• a hanger landed in the bore, the hanger having a hanger sidewall;
• a plurality of parallel circumferentially extending hanger sidewall ridges located on the hanger sidewall, each of the hanger sidewall ridges having upper and lower flanks that converge to a crest;
• a plurality of hanger sidewall bands, each of the hanger sidewall bands being located between adjacent ones of the hanger sidewall ridges;
• a metal seal ring having an outward facing seal surface in metal-to-metal sealing engagement with the wellhead housing sidewall and an inward facing seal surface in metal-to-metal sealing engagement with the hanger sidewall bands;
• the crests of the hanger sidewall ridges being embedded into the inward facing seal surface to restrict relative movement between the hanger and the seal ring;
• and
• a recess extending through each of the hanger sidewall ridges from the upper flank to the lower flank, the recess having a surface recessed from adjacent hanger sidewall bands, wherein a gap exists between a least a portion of the surface of the recess and the inward facing seal surface to allow fluid trapped between the hanger sidewall ridges to flow out.

A method for sealing between a hanger sidewall of a hanger and a wellhead housing sidewall of a bore of a wellhead assembly, comprising:

• (a) providing a plurality of parallel circumferentially extending ridges on at least one of the sidewalls, each of the ridges having upper and lower flanks that converge to a crest, with a sealing band located between adjacent ones of the ridges and a recess extending through each of the ridges from the upper flank to the lower flank, the recess having a surface recessed from adjacent sealing bands;
• (b) placing a metal seal ring having outward facing and inward facing seal surfaces between the wellhead housing sidewall and the hanger sidewall, respectively, and deforming the seal ring such that at least one of the seal surfaces is in metal-to-metal sealing engagement with the band, the crests of the ridges are embedded into said at least one of the seal surfaces and a gap is located between a least a portion of the surface of the recess and said one of the seal surfaces;
• and
• (c) forcing liquid trapped between each of the ridges through the recess while performing step (b).