brønnhoder

Brønnhoder, or wellheads, are a set of equipment installed at the surface end of an oil or gas well to provide the principal pressure boundary and mechanical interface between the subsurface reservoir and surface facilities. They are mounted on top of the casing strings and provide a reliable connection point for tubing and, in many cases, for production equipment such as a Christmas tree. The wellhead assembly supports the casing and tubing and seals the annulus, enabling safe well operations and permitting testing, commissioning, production, and intervention activities.

A typical wellhead configuration comprises a casing head, which sits on the surface casing and provides the primary seal; a tubing head, which supports the tubing string and houses tubing hangers; and a production tree or Christmas tree, which is mounted on top of the tubing head to regulate flow, monitor conditions, and control subsurface isolation valves. In offshore fields, subsea wellheads are installed on the seabed and connected to surface trees; in onshore fields, the wellhead is located at grade or in a wellhead yard.

Brønnhoder are designed to withstand high pressures, temperatures, and corrosive fluids, and are manufactured in accordance with industry standards (for example API 6A and ISO 10423). They form a critical safety and production platform, with regular inspection, testing, and maintenance required to ensure integrity.