Design of electronically controlled emergency shutdown system for well test operation

At present, offshore exploration well test is facing more and more testing of high temperature and high pressure wells, deep water wells, high production gas wells, and hydrogen sulfide containing wells, which is often challenged with downhole temperatures over 180 ℃, formation pressure coefficient over 1.3, and toxic and harmful gas in formation fluids.These challenges greatly restrict the development of engineering operation safety and testing technology for offshore exploration testing, making further improved safety standards for well test operation an inevitable trend in the development of the industry.Ground well test safety technology is an important part of offshore testing.The traditional emergency shutdown system (ESD) uses gas for signal transmission, resulting in poor stability of the shutdown system and long emergency response time of more than 15 s and leaving a great hidden hazard for and well tests safety.By investigating the existing domestic technology, technical innovation of traditional ESD system is conducted.The principle of traditional ESD system is redesigned to replace the gas control with the electric control.By replacing the traditional gas signal with the electric signal, the emergency shutdown time is reduced to 4 s, which ensures the on-site operation safety.The electronically controlled ESD system has been successfully applied to the well test operation of four exploration wells in Bozhong 19-6 Block, and the ground safety standard for offshore exploration well test operations has been technically improved.