OFFPIPE is a software program based on a nonlinear finite element method, specifically developed for marine pipeline modeling. This method is accurate and converges quickly for all pipe sizes and water depths.

In static analyses, OFFPIPE calculates pipe stresses and deformed geometry at all points along the pipe length and identifies all points where there are gaps in the pipe. For each extension pipe, OFFPIPE also calculates the pipe elevation above the pipe line for dynamic analyses, as well as the natural frequencies of the pipe lengths and determines the stresses and displacements resulting from wave and vortex loads. The results can be analyzed statistically to estimate the pipe's service life.

• Analysis functions include:
• Static and dynamic analysis of pipe laying for many laybarge and stinger configurations, conventional and J-shaped.
• Pipeline lay initiation analysis and abandonment and recovery analysis;
• Calculation of stresses, stretches and static deformations of pipes for irregular seabed scenarios;

Pipeline Laying Analysis

You can model pipelines in two and three dimensions (taking advantage of the reduced size of two-dimensional problems for faster execution). Three-dimensional static analyses can include current profiles, bed slopes, soil friction, and non-zero barge headings, as well as through-pipe displacements.

Using its optional dynamic analysis capability, the user can specify the RAOS barge and select a regular wave or wave spectrum. OFFPIPE will then calculate the dynamic response (including pipe stresses) for the pipe. It provides an interactive, menu-driven user interface where data is entered by filling in the blanks on a series of color screens. These screens are supported by a context-sensitive online help system.

The software features interactive output for graphically displaying calculation results and previewing output and printed graphics on the IBM PC screen. It generates hardware-compatible plot files for Hewlett-Packard laser printers and plotters. OFFPIPE provides a detailed laybarge model and a simplified structural model of the Stinger tool, including the effects of ballast and hinge scheduling between sessions.

Detailed pipe support models are included, which can include angled horizontal and vertical rollers, top restraints, and finite-length supports. Several options are provided for configuring barge and pipe support elevations. The seafloor is modeled as a continuous elastic-plastic base (not a series of support points). Lateral soil resistance is bilinear: elastic for small horizontal displacements and frictional for large displacements.

Other features include tube bundle modeling, buoys (external buoyancy), tube coatings and insulation, tube fluid content, nodal corrections, point loads, and much more.

System Requirements

• OFFPIPE runs on Windows 95/2000/XP-based systems. It leverages current hardware advances to provide fast, compatible calculations.
• Compatible with IBM x86 floating point
• CD and DVD drive
• Windows-based system (all versions including 95, 98, NT, 200