초록 ▼

A hybrid wellhead system is assembled using a plurality of threaded unions, such as spanner nuts or hammer unions, for securing respective tubular heads and a flanged connection for securing a flow control stack to a top of a tubing head spool. The tubing head spool is secured by a threaded union to

A hybrid wellhead system is assembled using a plurality of threaded unions, such as spanner nuts or hammer unions, for securing respective tubular heads and a flanged connection for securing a flow control stack to a top of a tubing head spool. The tubing head spool is secured by a threaded union to an intermediate head spool. The intermediate head spool is secured by another threaded union to a wellhead. Each tubular head secures and suspends a tubular string in the well bore. The hybrid wellhead system is capable of withstanding higher fluid pressures than a conventional independent screwed wellhead, while providing a more economical alternative to a flanged, or ranged, wellhead system because it is less expensive to construct and faster to assemble.

대표청구항 ▼

We claim: 1. A hybrid wellhead system, comprising:a wellhead supported by a conductor, the wellhead suspending a surface casing and an intermediate casing string in a well;an intermediate head spool secured to the wellhead by a hammer union, the intermediate head spool suspending a production casing

We claim: 1. A hybrid wellhead system, comprising:a wellhead supported by a conductor, the wellhead suspending a surface casing and an intermediate casing string in a well;an intermediate head spool secured to the wellhead by a hammer union, the intermediate head spool suspending a production casing string in the well; anda tubing head spool secured to the intermediate head spool by a hammer union, the tubing head spool suspending a production tubing string in the well.