SUBSEA AND PIPELINES ENGINEERING
Feasibility, Concept Selection, Pre-FEED Studies
Atteris’ experienced concept engineers will screen and define concepts at an appropriate level of detail for each stage of project definition. A small 1-2 week study might support an exploration well’s economic case. A several months duration Pre-FEED study might assess a wide range of value opportunities before selecting a concept to progress to FEED.
Concept Screening Workshops
Atteris’ wide-ranging concept screening workshops, which tap-in to the combined wisdom and creativity of the client’s team and Atteris’ subject matter experts, ensure that all reasonable design concepts are considered at an early phase of concept definition. Working with client’s team, Atteris can facilitate concept workshops which brainstorm alternatives, perform SWOT analyses, and agree a short-list of concepts for further technical evaluation.
Conceptual Development Layouts
Atteris can prepare concept development layouts ranging from a dimensioned sketch of the new facilities, through to a suite of detailed development layouts, including drill centre layouts and riser approaches for offshore developments, and pipeline alignments for onshore waterway, road, and rail crossings. Atteris’ concept drawings are sufficiently detailed to define key concept differentiators, whilst limiting unnecessary drafting effort which is more efficiently done at a later phase of design, once the concept is better defined.
Analogue Project Review And Benchmarking
Atteris’ collective project experience, and its in-house database of worldwide project data, enables it to identify analogue projects which can give a client better confidence that a proposed concept is technically and economically robust, and ready to proceed to the next project phase.
Subsea Architecture Definition
Good subsea architecture selection depends upon good definition of the constraints. Subsurface and drilling constraints drive wellhead locations, dropped object constraints drive equipment spacing, installation vessel constraints limit equipment sizes, future flowlines corridors constrain the foundation project’s flowlines, spool material selection drives spool sizes, etc. Atteris has “been there and done that” on countless projects, and can consider all of these issues, and many more, to achieve the best life cycle value in its subsea architecture designs.
Subsea- Systems Engineering
Atteris’ study managers are highly experienced in understanding clients’ subsurface (reservoir and drilling) and facility constraints, and collaborating with client’s subsurface teams and facilities teams to optimise project value.
Atteris’ experience through all phases of a project, from concept through to execution and operation ensures we understand and can identify key technical decisions which require integrating into our concepts to ensure feasibility for future development.
ENGINEERING DESIGN AND ANALYSIS
Atteris’ flow assurance capabilities include:
- Fluid sampling and offshore testing program definition, in advance of an exploration or appraisal well
- Fluid laboratory testing program definition
- Fluid characterisation (PVTSim or Multiflash)
- Flow assurance strategy selection, considering all aspects such as liquids management, hydrate management, wax, emulsions, asphaltenes, scale, etc.
- Subsea processing process design (HYSYS)
- Steady state and transient multiphase pipeline modelling (PIPESIM / OLGA).
- Preparation of operating procedures.
Atteris has in-house expertise to assist our clients with a range of material selection/assessment issues and their protection against corrosion and erosion associated with subsea and onshore pipelines and related structures. Depending on the complexity of the subject, Atteris will engage recognised subject matter experts as required. This approach has proven to deliver the best results.
Our engineering expertise includes:
- Materials selection and engineering, including non-metallic, carbon steel and corrosion resistant alloys linepipe
- Corrosion and erosion assessments
- Welding engineering
- Internal and external coating systems for flow assurance, corrosion prevention, insulation, weight coating
- Cathodic protection design and assessments
- Specifications and datasheets
Subsea System Technical Integration
Systems Engineering considers the entire development’s performance, from the reservoir through to the cargo offtake, and ensures that each major system element remains fully integrated throughout the asset lifecycle. It can prevent the enormous costs associated with under-designed or over-design of an element, relative to the greater system.
Atteris’ Systems Engineering approach is to:
- Maintain overall Safety and risk engineering oversight, with a particular focus on issues across system element boundaries, where a “cause” in one system element might result in a consequence in another system element designed by another engineering team.
- Actively coordinate inter-discipline engineering (e.g. subsurface-subsea, or subsea-topsides, or topsides-onshore, and the like.)
- Actively coordinate interface engineering between design teams and between major system elements
- Consider the full asset lifecycle, to ensure system elements aren’t relatively under or over designed at various stages of asset life
Pipeline Route Survey Support
Atteris has a long track record of supporting our clients with any type of route survey for pipelines, flowlines, umbilicals and cables, including:
- Survey plans and strategies
- Planning, cost estimating
- Scopes of work and specifications
- Project management and contract administration
- Offshore and onshore survey support including shore and waterway crossings
- Geophysical and geotechnical surveys
On multiple projects, an experienced and competent engineer was present on the survey vessel with the necessary computer hardware and software to support the client, and to assist selecting and narrowing down pipeline route options.
Pipeline Route Selection
Analysis selecting the most cost-effective route for pipelines, umbilicals and cables is arguably one of the most important decisions for your pipeline design for both offshore and onshore. Atteris employs engineers with the necessary expertise to select the best possible route for your assets.
Metocean, Geological and Geotechnical Assessments
Atteris has the in-house capabilities to undertake most metocean, geological and geotechnical engineering-related work. Atteris employs engineers with significant expertise in effectively managing specialist consultants in these fields for the more complex assessments and studies in these disciplines.
Pipeline Mechanical Design
Atteris has the capability and experience to perform mechanical design for all aspects of pipeline systems including:
- Onshore and offshore pipelines
- All pipeline sizes from large diameter trunklines to small diameter flowlines
- Deep and shallow water
- End connections including tie-in spools and risers
- Design in accordance with various codes including DNVGL, API, AS and ASME
- Materials selection and engineering, including non-metallic, carbon steel and corrosion resistant alloys linepipe, welding engineering, internal and external coating systems for flow assurance, corrosion prevention, insulation, weight coating
- Cathodic protection systems (impressed current and galvanic anode systems).
- Engineering criticality assessments (ECAs)
Pipeline Stabilisation Design
Atteris has pioneered a large number of innovative hydrodynamic stabilisation designs and methodologies for pipelines and related infrastructure, such as:
- On-bottom stability engineering assessments taking into account seabed instability processes such as scour and liquefaction
- Secondary stabilisation designs using rock bolts, rubble mound structures (rock berms) and gravity anchors
- Pipeline sheltering using pre-trenching and post trenching techniques
Between 2006 and 2010, Atteris, in conjunction with the University of Western Australia (UWA) and with support from Woodside Energy, pioneered the development of a more realistic pipeline on-bottom stability methodology, which takes into account the often complex seabed material local scour and liquefaction processes along pipelines. As part of a project, which assessed the hydrodynamic stability of a large diameter gas trunkline, Atteris convinced Woodside and UWA to undertake large scale model testing as a world first, to simulate the complex interaction between the movement of the water, the pipeline and the seabed material. This resulted in the development, construction and commissioning of the O-tube laboratory testing facility, which has been used multiple times since by Atteris to simulate the behaviour of pipelines, flowlines, umbilicals, rock berms, and concrete and steel mattresses under extreme hydrodynamic loading.
Safety and Risk Assessments
Atteris support’s its clients in performing safety and risk assessments (HAZOPS / HAZIDS) related to our designs and the associated construction activities, or as a consultant to your designs and operations. We have a proud track record of considering safety and risk in design and striving to maximise the inherent safety and demonstrate certainty in risk of the designs we produce. Our knowledge and experience of design, construct, and operated (IMMR) is a valuable asset to these processes.
Support to Project Approvals
Atteris has a long track record in effectively supporting project developers with environmental and regulatory approvals. Engineering support can be provided for:
- Offshore and onshore environmental impact statements
- Sea dumping permits
- Consent to construct applications
- Right of Way (ROW)
- Safety cases
- Attendance at meetings with government and regulators
- Pipeline licenses
Package Management and Project Engineering
Atteris has engineering professionals with significant expertise in project management and construction support. This includes:
- Development of tendering and contracting strategies
- Preparation of ITT documentation, such as contracts, pricing schedules, scopes of work, specifications and drawings
- Review of tender submissions
- Package management, project management, contract administration and construction supervision
- Project close-out reports
Atteris has in house expertise and software to perform installation analysis for pipelay, flexlay, umbilical lay, pull-ins, pull-outs, pipe-push, mechanical connection make-up, structure deployment etc. As well as performing high level studies to confirm installability of proposed designs in the early stages of projects, Atteris has on a number of occasions performed detailed installation analysis on behalf of construction and installation contractors.
Cost and Schedule Estimates
Atteris has advanced systems, comprehensive cost and schedule database and significant expertise in relation to the preparation of cost estimates and schedules for pipeline projects. Cost estimating and schedules can be performed deterministic as well as probabilistic, taking into account design, construction and fabrication, and commercial risks.
Atteris has a successful track record of supporting our clients in the field during construction activities, in particular where this involves overseeing the construction and / or installation of Atteris designed solutions. We have a firm belief that this serves the client in ensuring that no aspect of the design is overlooked in the construction stage, while also exposing our engineers to field operations and thus constantly improving our ability to ensure our designs can be efficiently constructed and installed.
Construction Method Development and Review
Construction and execution experience is a valuable part of a design engineer’s development. At Atteris we recognise this fact and have made this part of our development program for our engineers. Most of our engineers have a strong construction background, which we draw upon to develop and review construction methodologies, often running internal workshops to ensure the most constructible designs. Understanding construction methodologies early in your project phases will reduce risk of cost and schedule overrun during execution, maintaining project value.
Atteris understands Regulatory Compliance and can assist / manage the assembly of evidence required to demonstrate compliance in addition to performing engineering assessment as required. Atteris also has expertise in effectively managing regulatory compliance specialists for more complex submissions.
IMMR Engineering and Support
Inspection, Monitoring, Maintenance and Repair (IMMR) activities are cornerstone to successful risk management of offshore and onshore infrastructure. Risk based IMM plans and practical Emergency Response and Repair plans and procedures facilitate effective management of risk. We take a holistic and practical approach to IMMR engineering that considers project and location specific variables, operational constraints and system interdependences, and stage in the asset lifecycle.
The key to maintaining integrity of offshore and onshore infrastructure is through understanding credible risks to the system. Our holistic, practical and systemic approach to risk assessment returns a technically sound and realistic output. Our approach also considers the stage in the asset lifecycle. This is forms the foundation of an effective integrity management program to manage the risks, and one that maximises economic recovery without compromising on health, safety or the environment.
Integrity Management System Design
An effectively designed and implemented integrity management system is the backbone to successful management of offshore and offshore infrastructure. Our practical approach takes into account the policies and philosophy of your operations, available systems and resources, and stage in the asset lifecycle. The focus is on delivering a system that addresses the organisations key drivers, considers constraints of the organisation, project or operating location.
Offshore Pipeline Decommissioning Engineering Guideline
Atteris wrote the Offshore Pipeline Decommissioning Engineering Guideline for the Energy Pipelines Cooperative Research Centre (EPCRC). The guideline was developed in consultation with the Decommissioning Committee established by the Australian Petroleum Production and Exploration Association (APPEA).
At the end of an asset’s lifecycle, decisions around decommissioning must be made. To facilitate the decision making process, decommissioning studies can be performed to guide your operations through the technical, commercial and regulatory requirements for decommissioning options. Atteris provides the needed engineering support for decommissioning concept studies and methodologies, cost and schedule estimations, and onshore and offshore project engineering support through to completion of decommissioning works. Our approach is to focus on maximising economic recovery without impacting on health, safety or the environment.