A systematic approach has a major impact on costs already in the development phase. “As much as 90% of the cost of a technology development project is related to tests. Those that do not address the high-risk failure modes can be omitted,” says DNV Technology Services’ gas manager Erik Skramstad. Technology qualification is one of the key services DNV provides to the oil and gas industry.

The combination of DNV’s expertise in oil and gas technology and risk-management competence is highly valued by the industry worldwide.

”When we qualify technology, we follow a systematic process to identify the failure modes that might occur and how serious the consequences might be with regard to people, the environment and production. We also consider the probability of the failure mode occurring and thus manage to identify the failure modes that involve an unacceptable risk. These failure modes of concern – those that are most important – are taken further into a test programme,” explains Erik Skramstad.

The introduction of new technology often leads to unforeseen problems. In many cases, the operators experience that technology intentionally introduced as an improvement has led to unforeseen problems and unnecessary shutdowns, often involving huge costs. For instance, fatal accidents may be the results of gradually extending the application of known technology into tougher operating conditions without identifying possible obstacles. Among the about 150 failures investigated by DNV’s failure investigation laboratory each year, a considerable number relate to the use of new solutions and to the use of proven technology in new applications.

Building confidence in novel LNG technology
There is a quest for better and more efficient solutions throughout the LNG value chain. Larger and more effective liquefaction plants are being planned; larger ships with efficient propulsion plants and minimised boil-off with onboard re-liquefaction are being built; novel containment systems that challenge the traditional systems are being proposed; and new receiving terminals based on novel technology are being developed.

Despite the obvious need for new technology, the operators are generally reluctant to start using innovative solutions. The lack of operational experience represents an uncertainty about the reliability that the operators are not willing to accept. The objective of technology qualification is thus to bring the technology to the market by building confidence. This will be achieved by documenting that the technology has undergone a systematic qualification process showing that it meets specific reliability targets.

DNV has, in co-operation with industry partners, developed a Recommended Practice, DNV-RP-A203 ‘Qualification Procedures for New Technology’, which describes a risk-based work process to ensure that technology is qualified in a systematic and well-documented manner.

“The procedure is formulated generally, but has been primarily developed for areas where reliable functionality is essential to the economic success of a field development,” says Skramstad. He explains that technology qualification is a service DNV performs frequently for customers worldwide.

“If it lacks a track record, how can a novel system prove its functionality and reliability?” he asks.

Systematic approach
A key issue in DNV’s technology qualification service is its systematic approach to creating confidence in novel solutions.

“We add value to our customers’ business by ensuring a rational, systematic and well-documented qualification process in order to increase their confidence in their own decisions. This focuses on issues of high-risk impact and on reducing the risk of unforeseen events,” says Skramstad.

Technology qualification is the process of providing the evidence that the technology will function reliably within specific limits – by applying a structured approach to ensure a traceable and transparent qualification process.
This approach to qualifying new technology is a systematic qualification work process which can be conducted in parallel with the technology development project. Through co-operation between the various technology stakeholders, the qualification work process ensures that all aspects of novel technology are adequately addressed and the technology is proven to comply with stated functional requirements and reliability targets. In this respect, known technology in a new application is also included.

Technology assessment
The objective of the first technology qualification phase is to assess whether the novel concept is feasible. The process starts off by defining the qualification basis, with functional requirements and reliability targets which the technology is to meet. Then the system is divided into manageable parts, and classified with respect to novelty. Technology classification and a high level HAZID sort out the key technical challenges that need to be further assessed.

“A Statement of Feasibility certificate can be issued provided that it is certain that the major uncertainties related to the new technology aspects are likely to be resolved,” explains Skramstad.

Technology qualification plan
Following this, all potential failure modes of concern are identified by a thorough risk-ranking process and the qualification activities (tests, analyses, etc) needed to adequately address these failure modes are defined.
The activities of the qualification plan are then assessed with respect to the likelihood of these being successfully completed within the available time. Normally the assessment focuses on the technical challenge, but it can be expanded to include costs. If the probability of success of the project is acceptable, a Statement of Endorsement can be issued.

Technology qualified
Finally the activities of the technology qualification plan are executed to derive all the information needed to reduce the uncertainties to an acceptable level.

In this phase, DNV’s role is primarily to verify analyses and test reports and witness tests at defined hold points. A completed testing programme and a reliability analysis that confirms the availability stated in the qualification basis means that the Statement of Fitness For Service can be issued.

ITP InTerPipe
DNV has applied this approach to a variety of technologies since the code was issued in 2001. One example is the qualification of a subsea LNG pipeline for ITP InTerPipe. They developed a concept for submarine LNG pipelines to be used for LNG transport between facilities or to shore. DNV reviewed the pipe-in-pipe concept with the aim of qualifying the design and fabrication method and has issued a Statement of Feasibility. A set of recommendations was identified and will be followed up in later phases of the project.

Amplitude-LNG Loading System
Another example is the qualification of the Amplitude-LNG Loading System (ALLS). LNG is presently loaded over rigid loading arms from onshore terminals into LNG transportation vessels. As offshore solutions are attracting more focus, there is a need for new LNG-transfer technologies, such as the ALLS, which consists of a flexible cryogenic hose and a system for connecting the LNG vessel to the terminal or floating facility. The flexible hose is stored on the floating facility or terminal structure. Prior to LNG transfer, the hose is pulled over to the LNG vessel, guided into position and connected. Opening the double butterfly valves makes LNG transfer possible. A new emergency release system allows for fast disconnection in case of emergency by shutting the double butterfly valves and separating the hose and connection system – with the minimum spill of LNG. The Amplitude-LNG Loading System was developed by a Joint Industry Project (JIP) led by Technip France.

Sloshing
Another topic of interest to the LNG industry, and a highly relevant example of testing, is sloshing. Sloshing is a particular concern for membrane tanks in vessels operating in open seas with partially filled tanks. Standard-sized LNG carriers do not face this problem, but with larger carriers, offshore discharging carriers and floating terminals it is necessary to demonstrate that the sloshing loads are acceptable. DNV has a long history of conducting sloshing model experiments and the past two years have been a logical extension of that development work. Several phases of sloshing experiments have been conducted and the effects have been studied to learn as much as possible about this phenomenon in order to provide advice on design and operation and thus ensure safe operation.

Practical experiments were favoured over computer simulations because, despite computational fluid dynamics being a promising technique that can be used in study and development work, DNV believes this is not mature enough to provide the basis for important decisions such as partial filling approval.

While the first period of R&D studied sloshing behaviour and loads in depth, a comprehensive experimental and numerical programme to evaluate the structural response and strength has been conducted recently.
Currently, the sloshing research is in its final phase, with all the expertise and knowledge being used to develop guidelines. Issued as a Classification Note, they will provide clear guidance to owners and yards on how to assess sloshing in partially filled tanks for offshore offloading operations, milk runs or spot trading.

High value for the customer
Technology qualification is highly valuable for the industry. The application of DNV’s qualification work process to new technology and new concepts strengthens any project’s sponsors’ confidence in the projects being successfully executed. It is also of great value for a project to have important high-risk aspects addressed – thereby considerably reducing the risk of costly in-service failures.

“All this is in addition to the fact that technology qualification provides the technology owners with a selling argument for the later commercialisation of their technology,” says Skramstad.

For economic reasons, technology owners often need to attract interest from potential buyers before a decision to fully develop and qualify the technology can be made. To attract such interest, it is necessary to convince the buyers not only that the technology will provide a commercial benefit but also that there are no potential “show stoppers” that might prohibit successful qualification.

DNV uses experience and expertise
DNV has a long history and a broad basis in the LNG industry. In a fast-growing LNG market, where technical expertise is becoming a shortage, offshore experience is becoming more valuable and the safety, reliability, and functionality of novel technology is becoming more important, DNV has adapted its services to the LNG industry.
“DNV provides a full range of services related to all elements in the LNG chain, aimed at assisting our clients to build and operate their facilities in a financially sound, safe, reliable and environmentally friendly way,” concludes Skramstad.