Users can rapidly create and modify piping and structural models with time saving features such as automatic generation of elbows, tees, and reducers (eccentric and concentric). Users can graphically select portions of their model to assign or modify temperature and pressure loads, pipe sections, elbow radii, tee types and other parameters. CSiPlant offers options to replicate (copy/paste), rotate, slide, move and stretch selected objects in the model for faster, more efficient model creation and modification. Keyboard shortcut commands are available for more efficient modeling.

Piping Codes

CSiPlant currently offers the following piping codes:
  • • ASME B31.1: 2016, 2018, 2020, and 2022
  • • ASME B31.3: 2016, 2018, and 2020 (includes minimum temperature design curves for carbon steel to avoid impact testing )
  • • ASME B31.4 2019 (with collapse check per API RP 1111)
  • • ASME B31.8: 2016, 2018, and 2020 (Onshore and Offshore chapters with buckling check per section 833.10, collapse check per API RP 1111)
  • • GB-50251: 2015 (China) Gas Transmission Pipeline design 输气管道工程设计规范

ASME B31J SIFs and flexibility factor option available for all available ASME B31 codes.

Model Import

Users can easily import and combine multiple CSiPlant models which were created separately, including models which are disconnected from one another.


CSiPlant offers extensive temperature-dependent ASME B31 and ASME Section II-D material property libraries with code-based stress allowables, pipe section libraries for ASME B36.10 and B36.19, ASME B16.34 and B16.5 valve and flange library with temperature-dependent pressure ratings, multiple vendor libraries for valves and flanges and spring hangers. Steel frame section libraries for AISC (Imperial and Metric) and 13 International frame section libraries are also available. Additionally, users can add their own reusable libraries of pipe materials, supports (including gaps, friction, stiffness values), valves, flanges, and expansion joints.

Plans and Elevation

Plans and elevations views are automatically generated at every grid line to allow for quick navigation of the model.


Users can generate pipeline networks easily with CSiPlant drawing tools. A fully customizable labeling scheme is assigned for each pipeline, including points, supports, frames and links.

Property Modifiers

CSiPlant enables users to assign property modifiers which uses scale factors to amplify or reduce element stiffness separately in each local direction as well as scale mass and weight. Property modifiers may also be used to define rigid zero weight elements for modeling purposes.


CSiPlant offers standard sets of units for U.S. Customary, Metric SI, and Metric MKS which can be modified on the fly at any time. No matter what the current units, users can append input fields with mm, m, N, “, ‘, psi, and other designations to input in desired units which automatically converts to current units.


DirectX graphics with hardware accelerated graphics allow for navigation of models with fast rotations and multiple render modes including single line, double line and extruded.

Snap Tools

Snap tools including options to snap along lengths of object and orthogonal extension snapping capabilities.

Object Type


CSiPlant offers a suite of commonly used pipe supports for convenient modeling of boundary conditions. One point and two point supports are available, and CSiPlant pipe supports automatically connect to the outside diameter (OD) of the pipe with internal rigid links generated from the pipe centerline to the OD in each acting direction of the support. Users can create their own customized library of pipe supports, defining each individual property (including gaps, friction coefficients, linear or multi-linear spring properties, and damping constants), which can be used repeatedly throughout the model.

As a supplement to pipe supports, CSiPlant also offers 1-point and 2-point link objects for specialized force-deformation relationships for applications such as modeling base isolators, damper friction springs, and yielded damper coefficient behavior.

Flanges and Valves

CSiPlant offers unique options to specify both valve actuator and valve body weight and mass eccentricities.

For evaluation of external loads on weld neck flanges to avoid leakage, CSiPlant provides built-in design checks per ASME Sec. VIII-1 paragraph UG-44 (formerly Code Case 2901) which represents ASME's latest research.

Spring Hangers

Using built-in vendor libraries, CSiPlant can automatically select variable or constant spring hangers to meet user specified design criteria for maximum load variation percentage, displacement thresholds, and installation method. Users can evaluate spring hanger design criteria using design requests to assess model sensitivity.

Graphical Modification of Elements

Users can graphically select components to modify elbow radius, reducer length, reducer cone angle, tee dimensions and tee type of selected objects, while also automatically adding flanges to the ends of selected valves, elbows, tees, and reducers. Elbows can be automatically converted into tees, and vice versa, for rapid modification of the piping model.


CSiPlant frame elements are fully featured with end release options for all 6 DOF with or without partial fixity, TOS, BOS and other cardinal insertion points. Nonstandard frame sections such as plate girders or concrete sections can easily be defined and included in the model. All load types (except for internal pressure and including thermal gradient), distributed supports (soil), regular supports, and joint restraints can be assigned to frame elements.


CSiPlant offers many different link elements available that accurately represent the behavior of a structure. Link elements types include linear, multi-linear elastic, multi-linear plastic, gaps, hooks, dampers, friction isolators, rubber isolators, and T/C isolators.

Pipe Properties

Pipe properties including insulation, cladding, pipe contents and lining type can be defined in CSiPlant.

Expansion Joints

CSiPlant expansion joint component offers options to define and model tie rods, with or without gaps, hinge joints and gimbal joints. Effective inside diameter for consideration of pressure thrust and linear or multi-linear breakaway stiffness values in each direction can be defined. The advanced option enables users to define multilinear force/displacement and moment/rotation relationships in each selected degree of freedom, making it also suitable for modeling ball joints and telescoping slip joints among other applications.

Soil Modeling

Soil supports can be linear or multilinear distributed supports assigned as a stiffness per unit length, with different stiffness properties in each direction, and CSiPlant will automatically discretize the model with options to control the internal meshing. Distributed supports can be assigned to pipe and frame elements, enabling users to consider soil/structure interaction of piles and sleeper supports on soil in addition to buried and subsea pipeline applications. CSiPlant also offers built-in American Lifelines Alliance (ASCE) soil property guidelines.

Flexibility Factors

CSiPlant offers built-in local flexibility calculations for branch connections and nozzle/vessel junctions per ASME B31J. For those branch connections and nozzle/vessel junctions which do not meet the dimensional requirements of B31J, users can easily enter stiffness values for local flexibilities calculated from SAP2000 finite element models or from another 3rd party software program.


Load Cases

An infinite number of load patterns, load cases, load case types (thermal, seismic, modal, etc.) or model size can be analyzed in CSiPlant. Acceleration loads can be applied as static G or as time history acceleration loading in all 6 degrees of freedom. CSiPlant accounts for changes to Poisson effect behavior due to external pressure which can vary as a function of depth. Users can specify which load cases are designated to a particular design category with additional options in the Design Request dialogue. Load cases can be combined (Algebraic, Absolute, SRSS) or load sequenced.

Automatic Code-Based Loading

CSiPlant will automatically generate and apply seismic and wind loads based on various domestic and international codes.

Load Assignments

CSiPlant is robust when it comes to load assignment. Uniform distributed line loads can be assigned in any local or global direction. Thermal, strain and internal and external pressure loads can be assigned any pipes. Point loads and ground displacement can be assigned to any joint.

Mass Source

CSiPlant enables users to define an unlimited number of “Mass sources” which can convert selected gravity-direction assigned loads into equivalent mass in all 3 translational directions for use in static acceleration load cases and in all dynamic analysis load cases. This unique capability is critically important for pipe/structure interaction.


P-Delta Analysis

CSiPlant offers P-Delta analysis, including P-Delta with large displacements, with minimal additional modeling and analysis time.


Dynamic analysis capabilities include the calculation of vibration modes using Ritz or eigen vectors, response-spectrum analysis, and time-history analysis for both linear and nonlinear behavior.

Path Dependent Load Sequencing

Nonlinear load cases can be sequenced and chained together using the “Continue from End State of” field in the load case dialogue. Path dependent load sequencing, which specifies the order of the applied loads, can often make a difference in design calculations when friction or soil are modeled and in load cases with P-delta. Since dynamic excitations most often occur when the piping is operational and thermally displaced, the ability to load sequence modal and time history cases can offer more realistic analysis and design results.

Ritz Vector

Ritz vector modal analysis can provide a better basis than eigenvectors when used for response-spectrum or modal time-history analyses. Ritz vectors yield better results as they are generated by taking into account the spatial distribution of the dynamic loading, whereas natural mode shapes neglect this.

Response Spectrum

Response-spectrum analysis determines the statistically-likely response of a structure to seismic loading. This linear type of analysis uses response-spectrum ground-acceleration records based on the seismic load and site conditions, rather than time-history ground motion records. This method is extremely efficient and takes into account the dynamical behavior of the structure.

Time History

CSiPlant offers linear and nonlinear time history dynamic analysis options. Users generate a time history function by importing from a file or manually inputting the time history data and then applying it to a time history case. CSiPlant time history cases can analyze point force vs time, acceleration vs time, imposed displacement vs time, temperature or pressure load vs time, and strain load vs time. By analyzing seismic loads as nonlinear time history cases, engineers can consider more realistic seismic load distribution on the piping and structure while accounting for nonlinear boundary conditions and P-delta effects.


Buckling can be a design concern in several different piping applications including buried and seabed pipelines, GRP and plastic piping, rack piping with intermediate anchors, and tall vertical risers among other design scenarios. Using both eigen buckling and nonlinear large displacement buckling analysis options, CSiPlant makes it convenient for engineers to check for buckling during design.

Nonlinear Time History Dynamic Analysis

CSiPlant offers linear and nonlinear time history dynamic analysis using modal and direct-integration methods. There is no practical limit to the number or size of time history cases which can be analyzed. Time history cases can be load sequenced to continue from the end state of a nonlinear load case for more realistic analysis results, and nonlinear time history analysis cases can account for gaps, multi-linear support behavior, friction, and P-delta effects in the dynamic analysis.

Nonlinear Load Sequencing

CSiPlant offers unlimited nonlinear load sequencing, also known as path-dependent loading, which considers the order of the loading. Since friction acts in different directions during startup vs. shutdown and other load states, sequenced loading, including sequenced thermal loading and unloading, is often needed to determine worst case reactions and stresses. Since dynamic loads typically strike when the piping is operational, load sequencing can provide more realistic dynamic analysis results.

Time History Load Function Generator

CSiPlant’s time history load function generator enables engineers to quickly generate time history load functions used in time history load cases, including sinusoidal loads such as piping pulsation loads and unbalanced vibrating machinery loads.

The ‘Import from File’ option is used to import loads, like waterhammer or steamhammer loads, from 3rd party fluid transient programs and for importing seismic ground motion acceleration records (time vs acceleration) from databases like PEER. This import file option automatically handles scientific notations in the text file. Nonlinear time history analysis enables users to account for nonlinear friction, gaps, one-way support behavior, and P-delta effects in the dynamic analysis as a more accurate alternative to linear-only response spectrum or steady state harmonic analysis methods.


Design Requests

CSiPlant offers a unique and powerful design request feature which can consider multiple different design parameters all in one run for side-by-side evaluation. Users can specify and evaluate unique configurations and different parameters for each different design request. Design parameter selections that alter the stiffness matrix for analysis are handled automatically by the design request using its stage construction capability.

Since exact friction values are not always known and may change over time, each design request can apply a friction scale multiplier to any supports with friction applied. This enables users to analyze and design for multiple different friction coefficient scenarios all in the same run.

Output and Display

Deformed Geometry

Deformed geometry can be displayed based on any load or combination of loads, as well as animations of modes.

Pipe Frame Forces/Stresses

Stresses and element forces and moments are calculated and reported at multiple stations along the length of each element, not just at meshed point/node locations. Display of pipe/frame forces and stresses can be based on load case, load combination, or modal case. Users can show resultant forces and stresses on any component in any direction. Control the stress contour appearance by showing undeformed, deformed, or extruded shapes, with or without loading values.

Tabular Output

CSiPlant has the ability to display tables for all input data, analysis results, and design results. Tables support sort, cut, copy, and paste for use in other programs. Print or save tabular data to Access, Excel, Word, HTML, or TXT.

Center of Gravity (CG) Calculations

Weight of equipment, cable trays and other items may be assigned as a distributed load or concentrated point loads in the analysis model. You can select which loads to include in a Center of Gravity (CG) case and multiple CG cases can be defined and evaluated in the same analysis.

Results Display

Graphically display analysis and design results with visualization tools to quickly assess problems and evaluate modifications. For example, users can have up to 4 windows displayed simultaneously for color-coded graphical display of deflection values, code stress ratios, element forces/moments, and Von Mises stress results, each window displaying a user selected result type, for a chosen load case in a specified direction.

Import and Export

Comprehensive Integration

CSiPlant allows for integration between piping stress and structural analysis programs. Import detailed SAP2000 structural analysis models into CSiPlant and auto-connect to the piping stress model for coupled nonlinear analysis and design. Import geometry from CII neutral file.

SAP2000 Interoperability

CSiPlant can import detailed SAP2000 structural models including load assignments, releases, and mass model definitions, and auto-connect with the piping model using 2-point pipe supports for combined nonlinear pipe/structure analysis to obtain more realistic reactions and stresses.

Selected pipe support reactions from the combined model can be automatically exported back into the SAP2000 structural model. CSiPlant and SAP2000 make it easy and reliable to rigorously consider pipe/structure interaction.


With cooperation from Dynaflow Research Group BV (DRG), CSI has developed the ability to import piping pulsation loads from reciprocating equipment generated from DRG's BOSpulse software which uses API 618 and API 674 guidelines. The CSiPlant BOSpulse import generates sinusoidal time history functions for the pulsation loads which can be analyzed as nonlinear time history cases to account for friction, gaps, and P-delta effects. Energy dissipation devices may be included in the model using CSiPlant's damper support or damper link elements.