An apparatus operable is a hazardous area for controlling a choke assembly includes an air source, an air purge system in fluid communication with the air source, a remote operating panel receiving data from at least one remotely located wellbore sensor, a local operating panel in electronic communication...http://www.google.fr/patents/US7478672?utm_source=gb-gplus-shareBrevet US7478672 - Apparatus for controlling a pressure control assembly in a hazardous area
Apparatus for controlling a pressure control assembly in a hazardous area
