About: http://webisa.webdatacommons.org/336382934

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	Accordingly, there is a need for a cementing head which may be both reciprocated and rotated simultaneously with the pumping of cement through the apparatus and down the drill pipe string.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com