Seal system for annular components

A lubricator for a pressure control equipment stack, the lubricator comprising:

• a first annular lubricator section comprising a radially-outer surface with a first threaded portion and a first sealing portion, wherein the first sealing portion comprises a first angled surface that is oriented at a first angle relative to a vertical axis;
• a first annular connector component comprising a radially-inner surface with a second threaded portion and a second sealing portion, wherein the second sealing portion comprises a second angled surface that is oriented at a second angle relative to the vertical axis, the first angle and the second angle are between 5 and 25 degrees, the first angle is about 1 to 10 degrees less than the second angle, and lengths of the first angled surface and the second angled surface are within 2 to 20 percent of an inner diameter of the first annular lubricator section;
• and
• an annular collar disposed at least partially about the first annular connector component, wherein the first annular connector component is radially between the first annular lubricator section and the annular collar, the annular collar comprises a first radial protrusion that axially abuts against a second radial protrusion of the first annular connector component, the annular collar comprises a third threaded portion separate from the first threaded portion and the second threaded portion, and the second radial protrusion is disposed axially between the first radial protrusion and the third threaded portion;
• wherein the first annular lubricator section and the first annular connector component are configured to couple to one another via the first threaded portion and the second threaded portion and to form a metal-to-metal seal against one another via the first angled surface and the second angled surface.

A method of sealing a first annular component to a second annular component, the method comprising:

• positioning the first annular component within the second annular component, wherein the first annular component comprises a first threaded portion and the second annular component comprises a second threaded portion;
• rotating at least one of the first annular component and the second annular component to thereby threadably couple the first annular component to the second annular component via a threaded interface of the first threaded portion and the second threaded portion and until only a first portion of a first angled surface of the first annular component contacts and forms a metal-to-metal seal against only a second portion of a second angled surface of the second annular component, the first angled surface is oriented at a first angle relative to a vertical axis, the second angled surface is oriented at a second angle relative to the vertical axis, the first angle and the second angle are between 5 and 25 degrees, the first angle is about 1 to 10 degrees less than the second angle, and lengths of the first angled surface and the second angled surface are within 2 to 20 percent of an inner diameter of the first annular component;
• and
• positioning an annular collar at least partially about the second annular component, wherein the second annular component is radially between the first annular component and the annular collar, the annular collar comprises a first radial protrusion that axially abuts against a second radial protrusion of the second annular component, the annular collar comprises a third threaded portion separate from the first threaded portion and the second threaded portion, and the second radial protrusion is disposed axially between the first radial protrusion and the third threaded portion.