About: http://webisa.webdatacommons.org/252455208

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	This invention relates generally to oilfield well operations and more particularly to an apparatus and method for rotating a portion of a drill sting in a subterranean wellbore.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com