Fitness for Purpose Evaluation

• Smart pig data analysis and 3rd party review
• Demand-capacity and code compliance for burst, wrinkling and collapse
• Pipeline-soil interaction analysis including frozen soil conditions
• Evaluation of corrosion and metal loss
• Recommendations for mitigative and/or repair programs
• Evaluation of ripples and wrinkles in pipeline cold bends

• Innovative design concept evaluation
• Key design parameters and load definition
• Preliminary structural design
• Structural design criteria development
• Highly Tensioned Suspended Pipeline (HTSP) spans
• Leg off pipeline configurations
• Recommendations for mitigative designs and monitoring procedures

• Frost heave and thaw settlement design
• Bend design
• Design for offshore arctic loadings
• Monitoring program design
• Strain and structural criteria development

• Fault crossing analysis and design
• Traveling wave effects
  
• Dynamic spectral and time history analysis of piping systems and structures, including pipe-on-bridge and station/tank farm piping
• Liquefaction and landslide analysis

Testing Programs

• Design of structural testing programs
• Full-scale or component testing
• Instrumentation design and data acquisition
• Data analysis and model correlation

• Complex pipe stress analysis
• Transient analysis of relief systems
• Vibration analysis and mitigation
• Horizontal Directional Drilling (HDD) evaluations
• Evaluation of fill and traffic loads on buried pipelines

Arctic Pipeline Expertise

SSD, Inc. has extensive experience with Arctic pipeline projects dating back to the design stages of the Trans-Alaska Pipeline System in the 1970’s and carrying forward with ongoing work in all of the main North Slope oil fields (Kuparuk, Prudhoe Bay, Alpine, Badami, Milne Point, Northstar, Endicott, Lisburne, etc.). Our experience with chilled Arctic gas pipeline projects includes all ofthe major Alaskan and Canadian gas line studies undertaken over the last 30 years. Our work on these projects included extensive pipeline deformation analysis for frost heave and thaw settlement loads using our PIPLIN computer program, correlation analysis with full-scale pressurized pipe bending tests, as well as processing and model fitting of stress-strain relationships for a wide range of pipe steel grades up to X100 and X120. The buried pipe deformation analyses are used to consider a range of parameters including heave and thaw span length, pipe steel material properties, frozen pipe-soil spring strength, pipe operating conditions, etc.

SSD’s PIPLIN Program

Download PIPLIN References - pdf

PIPLIN has been aiding pipe designers and engineers for over 30 years throughout North America. The program considers several nonlinear aspects of pipeline behavior, including pipe yield, large displacement effects and nonlinear soil supports. The program also considers frost heave, creep and temperature dependent uplift and longitudinal pipe-soil springs. Pressure, temperature, settlement and gravity type loads are assumed to be applied statically. Arbitrary sequences of loads, including cyclic and non-proportional loads may be specified. The nonlinear problem is solved by a step-by-step procedure with an advanced event-to-event solution strategy.

The program is well suited for specialized analyses such as sidebend and overbend analysis of buried pipe with rational treatment of anchorage length, settlement and excavation analyses including cable action, fault motion of buried or aboveground pipe, analysis for liquefaction and lateral spread as well as sophisticated pipe pre-straining capabilities that allow for accurate characterization of pipe steel material anisotropy. The PIPLIN output includes pipe displacement; anchor and soil support deformations and reactions; pipe axial forces, bending moments and curvatures; axial and hoop stresses and strains in the pipe, arranged in a compact tabular form.

SSD also has the capability to modify the PIPLIN code to meet project-specific requirements. For quality assurance purposes, PIPLIN is validated against a comprehensive set of over 300 different benchmark tests which include comparisons with independent theoretical calculations or the results obtained using other well established computer programs.