Peritus experience and capability in wall thickness design covers all major design codes such as ASME, ISO and DNV along with country specific standards like NEN, BSI. Peritus also has significant experience designing to company design guidelines including Shell, Total, Petrobras and many others. We have optimised the design of wall thickness for ultra-deep water pipelines where mill capacity and ovality become governing criteria. This experience also covers issues such as sour service and the design of buckle arrestors.

Peritus has undertaken material selection and corrosion assessments for a large number of pipelines with a huge range of fluids transported. This includes sour service assessment, ECA and fracture toughness, materials mapping along with the design of CO2 and H2 pipelines and ancillaries.

There are a large number of potentially conflicting code and company requirements for offshore pipeline design. Peritus has experience working within these code constraints. However sometimes it is necessary to go beyond the design code and prove acceptability using other criteria such as the results of finite element modelling. Peritus skill and expertise in engineering along with their experience liaising with verification bodies will ensure the designs proposed are optimised, robust and acceptable.

Pipeline routing requires a combination of excellent software skills (GIS, Fledermaus, AutoCAD etc) along with a thorough understanding of the requirements of the installation contractor, this may also include requirements for trenching or buckle remediation schemes. Peritus have supported projects from the initial concept route selection, through to the detailed design engineering of a suitable final route including the selection and design of the landfall.

Where an external coating is subject to temperatures below 80°C the standard design codes and commonly used methods provide good protection solutions for pipelines, however above 80°C the standard coatings and anode solutions require more advanced design solutions and sometimes additional requirements such as pipeline cooling need to be considered and therefore the coatings must aid this. Peritus has experience with a wide range of coatings including specialist protection for areas such as the landfall (or HDD) pull in.

Peritus have experience in the assessment of freespans as well as the establishment of suitable assessment criteria for use offshore. We fully understand isolated and interacting freespans and have validated in-house models to accurately model the pipeline frequency response in position on the seabed.  Our engineers are experienced in the use of DNV Fatfree as well as other software which may be needed to assess more problematic span configurations such as ABAQUS, ORCAFLEX, SHEAR 7 etc.

Standard pipeline expansion calculations can be performed on our in-house validated worksheets. These take account of rock dump and other potential restraints. More specialist assessments such as sliding bundle and pipe in pipe systems where the different pipes expand at different rates causing a problem for bulkheads and internal fittings is another area where Peritus employees have an excellent understanding and have performed numerous detailed designs.

Bottom roughness is the process of assessing pipeline stresses and freespans using a finite element model that covers the whole length of the pipeline. Peritus have undertaken numerous bottom roughness assessments during the design phase in order to establish pre and post-lay remediation and rectification requirements. We are also experienced in as-built assessments to ensure the as-laid pipeline remains within the design parameters.

The connection between a pipeline and a structure, or platform is often achieved with the aid of a spool piece in order to isolate the expansion movement of the pipeline from the connected structure or platform.  This interface is often critical and special attention is required to the loads imparted on the flanges and the riser. Peritus has designed spools for connection to all types of structures and platforms along with spools in seismic areas with liquefied soils.

Peritus has experience in the design of a number of different types of riser. This includes the design of the riser, the associated clamp design, flange and hang off design. We are well versed in modelling direct wave action along with Vortex-induced-vibration (VIV). We have also designed riser protection structures and retro fit (replacement) risers in complex and congested environments.

High pressure and/or high temperature pipeline design requires the specialist engineering knowledge and tools that Peritus has developed over many years of designing and assessing HPHT projects. These include finite element design tools, materials assessment and ECA along with the design of buckle mitigation schemes or other axial force reduction measures.

Pipe soil interaction is of critical importance to the accurate assessment of a range of pipeline design activities including, buckling, stability, freespans, expansion and installation. Peritus has experience with a wide range of soil types including liquified soil, seismic areas, calcenerite soils and many types of rock including scour protection.

Peritus are experienced in the assessment of buckling potential as well as the design of buckle mitigation schemes. These include the use of sleepers, Zero Radius Bends (ZRB’s), light pipe segments and others depending on the project.

Peritus are experienced with the assessment of pipeline walking and the design of walking mitigation schemes including the design of anchor piles.

The design of pipeline bundles requires complex analysis and assessment of multiple pipelines with various materials and fluids to be transported. Assessment and analysis of bulkheads is a complex matter requiring detailed finite element modelling. Peritus have the software tools and experience required to undertake these analyses.

Peritus has designed landfalls for pipelines and cables including complex piggybacked systems. We have experience with open cut landfalls, micro tunnels, horizontal directional drills (HDD) along with the design of the transition in the near shore area to normal lay and/or trench protection.

Peritus has designed buckle arrestors for pipelines at depths of up to 3500m. We are experienced in the calculation of wall thickness for buckle arrestor pipe joints as well as the design of forgings and using J-lay collars for buckle arrest. We have also designed arrestors for the arrest of running ductile fractures in CO2 pipelines.

Peritus have designed J-lay collars for a number of installation contractors, this includes the full design of the forgings.

Peritus are experienced in the assessment of iceberg interaction with pipelines, this includes the full finite element modelling of the ice berg and associated trench scoured into the seabed. The response of the pipeline to the stress imparted into the soils by the iceberg can be rigorously assessed.

The assessment of geohazards encompasses a wide range of potential issues including the crossing of very steep continental slopes, slope failure, turbidity flows, liquefied soils, highly variable soils etc. Peritus has finite element tools enabling the accurate assessment of the interaction with potential geohazards and pipeline systems.

Peritus are experienced with all of the various seismic hazards including soil liquefaction, slope failure and fault crossings. We have finite element tools to accurately assess the effect of these issues on the pipeline systems.

Peritus have prepared specifications for both procurement and construction for a wide range of items and for a large number of clients.

In order to ensure that items remain within the design and engineered parameters, peritus have written installation procedures and manuals for a variety of clients and a number of installation contractors. We can also provide reps offshore to ensure installation is undertaken in accordance with the prepared procedures.

Peritus personnel have provided decommissioning advice and assistance to a variety of clients including Natural England, this includes comparative assessments as well as analysis of reverse S-lay and other pipeline removal methods.