Top drives with shaft multi-seal

US7748473B2 · kind B2 · utility

Assignee

• National Oilwell Varco, L.P. · US

Inventors

• Lawrence E. Wells · Yorba Linda, US
• Preston R. Fox · Willow View Lane, US
• Cliff Swiontek · Brea, US
• Svein Stubstad · Houston, US
• Howard Ervin · Spring, US
• James D. Brugman · Spring, US
• Paul Conover · Cypress, US

Key dates

• Filing date: Jul 11, 2008
• Grant date: Jul 6, 2010
• Expiry date: Jul 24, 2028

Classification

• Technology area (CPC E): Fixed Constructions
• CPC primary: E21B19/16
• WIPO field: Civil engineering
• WIPO sector: Other fields

Abstract

A top drive system for wellbore operations, the top drive system including motor apparatus, a main shaft driven by the motor apparatus, the main shaft having a top end and a bottom end, a quill connected to the main shaft, a gear system interconnected with the quill and the motor apparatus, and a multi-seal system for sealing against the quill. This abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims, 37 C.F.R. 1.72(b).