... rig ,Drilling Rig,API 4F,8A export 100% to USAChina factory pricesWe are manufacturer and OEM of NOV corporation.Core components ... the online monitoring system for working s tatus of mechanical, electric, hydraulic and pneumatic implements, failure alarm and failure self-diagnosis ... rig,Drilling Rig,30,40,50,70,90DBS,drill rig,factory price,09new style,tech from USA