Natural Gas and Oil Well Equipment Installation and Maintenance,Constructional And Engineering Contracting Related To Technology Projects - Final Handover,Oil and Natural Gas Pipelines Construction Contracting,Tinging and Painting Works,Metal and Iron Works,Oil and Gas Production Facilities Operation and Maintenance Services,Oil and Natural Gas Pipe Lines Installation and Maintenance,Oil Tanks Instqllqtion and Repair, : Technical maintenance of factories and oil installations(0910009),Onshore And Offshore Oil And Gas Fields And Facilities Services,Metal construction contracting,Mechanical Contracting,Electrical Contracting,Contracting Transmission Networks and Distribution of Water,Scaffold Installation Works,