BOEMRE PROPOSAL FOR A RECOMMENDED PRACTICE TO ADDRESS SUBSEA SAFETY SYSTEMS
We appreciate the API allowing the Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE) to present our proposal. We have been asking the API for a number of years to develop a Subsea version of API RP 14C for subsea safety systems. Of course this would be an API RP 17 series document.
The BOEMRE has established the requirement for subsea safety systems for deepwater projects through the Deepwater Operations Plan approval process. We have been granting these approvals for more than 15 years and have tried hard to be consistent in our approvals. Our understanding of the requirements for subsea safety systems have evolved over time as technology has evolved. We believe that the technology and requirements for subsea safety systems has gotten to a point where the API should capture all that has been learned in a subsea safety system guidance document.
The BOEMRE has developed some policies to provide guidance to the industry about what will be required of their subsea safety system to receive approval for their Deepwater Operations Plan.
We would like to offer these policies as a straw man to help kick off the new recommended practice for subsea safety systems:
In 2009 we published NTL No. 2009-G36, Using Alternate Compliance in Safety Systems for Subsea Production Operations (16 pages long)
The basis of this policy is called the Barrier Concept. The Barrier concept establishes that the most important valve in the subsea safety system is the Flowline Boarding Shut Down Valve (BSDV). The BSDV is designed to protect people and the facility from the subsea hydrocarbon sources in the event of a fire or an emergency condition. This policy also addresses the subsea well safety valve requirements. These valves are the Underwater Safety Valve (USV), Alternate Isolation Valves, and the SCSSV. This policy establishes the subsea valve closure requirements for following emergency conditions: Process Upset, Pipeline PSHL, platform Emergency Shut Down (ESD), Platform Temperature Safety Element (TSE) and BSDV TSE. This policy considers Electro-Hydraulic systems, Direct Hydraulic systems, and Electro-Hydraulic systems with loss of communication. This policy also defines the testing frequency for the ESD Logic and ESD Function test, and the testing frequency and allowable leakage rates for the BSDV, USV, and the SCSSV. For production operations, all subsea safety systems upstream of the BSDV are addressed by NTL No. G-36 and all surface safety systems downstream of the BSDV are addressed by API RP 14C.
We have two additional policies that will be published soon. Even though these policies have not been published yet, they reflect the requirements that currently appear in the Deepwater Operations Plan approval letters. These policies are:
First draft policy, Using Subsea Pumping for Subsea Production Operations (8 pages long)
This policy addresses the two different methods for utilizing electrical subsea booster pumps installed within the production flowline to increase production and hydrocarbon recovery. One method is to install a flowline with a maximum allowed operating pressure rating greater than the maximum possible discharge pressure of the subsea booster pump. The second method is to install a flowline with a maximum allowed operating pressure rating less than the maximum possible discharge pressure of the subsea booster pump. This policy establishes the sensor instrumentation, valve closure, and testing requirements for these two methods of subsea pumping.
Second draft policy, Using Secondary Recovery Methods Including Gas Lift and Water Flood for Subsea Production Operations (22 pages long)
This policy addresses the subsea safety system requirements of subsea water injection wells and various methods for subsea gas lift. Gas lift is being applied by connecting the gas lift supply line subsea to the well’s production casing or the wells production Flowline or a production manifold or to the base of the production risers. Each gas lift case has specific safety system requirements.
There are additional policies that are either published or waiting for publication that may be useful in the development of a subsea safety system recommended practice. You may want to look at NTL No. 2009-G24, Supervisory Control and Data Acquisition Systems or NTL No. 2009-G28, Alternate Compliance and Departure Request in Pipeline Applications. We will be publishing soon, Using High Integrity Pressure Protection Systems in Subsea Production Flowlines systems.
Questions:
FO/Tech Assessment/Hoshman file/Hoshman file/Standards/Presentation