About: http://webisa.webdatacommons.org/125710938

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	To serve as a pressure vessel, the body and ram block material must meet certain specifications to resist stress cracking in the presence of such chemicals as hydrogen sulphide.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com