The simplified landing string is introduced to Liuhua 4-1 Field for the installation of subsea Christmas tree (XT) tubing hanger, considering the low pressure in reservoir and absence of shallow gas. After demonstrating the feasibility of the simplified landing string system, the main equipment of this system is introduced, including the simplified landing string, umbilical system, tubing hanger running tool and tubing hanger. Then the control factors and restriction conditions are represented, followed by the detailed description of installation steps. Finally, a comparison is made between the application of conventional landing string and simplified landing string. The results can offer a reference for the exploitation of marginal subsea fields.
International Organization for Standar dization. ISO 10423-2009. Petroleum and natural gas industries. Drilling and production equipment: wellhead and Christmas tree equipment[S].2009.
[3]
International Organization for Standar dization. ISO 13628-6. Petroleum and natural gas industries. Design and operation of subsea production systems. Part 6: Subsea production control systems[S].2006.
[4]
International Organization for Standar dization. ISO 13628-4 Petroleum and natural gas industries. Design and operation of subsea production systems. Part 4: Subsea wellhead and tree equipment[S].2006