Design & Analysis

From failure analysis to failure prevention

Many different aspects need to be considered for the design of a fiberglass system. Our Design and Analysis Services consist, specifically tailored to fiberglass piping, the following:
  • Pipe Wall Thickness Calculations
  • Pipe Stress Analysis
  • Buried Piping Analysis
  • Surge Analysis
  • Dynamic Stress Analysis
  • Product Development

FRP Analysis Types

Pipe Wall Thickness Calculations

Pipe Wall Thickness Calculations

DRG determines or reviews the suitable pipe wall thickness in an early stage of the project, taking into account the vendor’s proprietary pipe and component design and type of application. These calculations are often performed in close connection with the material qualification program.

Pipe Stress Analysis

Pipe Stress Analysis

DRG assesses whether the structural integrity of the piping system can be guaranteed conform the FRP standards such as ISO 14692. Attention is given to the FRP specific features such as for example non-standardized material properties, non-tensile joints and thrust blocks, which do not play a role for metallic piping.

Buried Piping Analysis

Buried Piping Analysis

In buried piping analysis DRG verifies the pipe for backfill conditions, settlement conditions, loads at road crossings as well as many other load types. Different solutions exist to solve overstressed conditions and these are chosen in consultation with client.

Surge Analysis

Surge Analysis

Surge analysis can find potential overpressures, vacuums and unbalanced loads. DRG performs the surge analysis and also runs a dynamic stress analysis with its integrated software. This way, we can recommend the necessary mitigation measures.

Dynamic Stress Analysis

Dynamic Stress Analysis

DRG performs dynamic stress analysis for fiberglass piping to assess stresses due to waterhammer, seismic loads or vibrations. This can be part of a design study or troubleshooting for an operational plant.

Product Development

Product Development

DRG applies its in-depth knowledge of the fiberglass laminate material to assist manufacturers to develop new pipe wall architectures, fittings or other pressure-holding components. Finite Element Analysis is an often used tool in the development.
GRE endcap modelled using FEA

FRP Product Development

When you as a manufacturer wants to set up a new product line DRG can assist in the design of components like flanges and fittings, but we can also assist in preparation of a qualification- and QA/QC test plan or ”Inspection Test Plan” (ITP).
With our in-depth knowledge of the materials properties of the components used in a composite pipe, like glass fibers and resin, we can also assist to find the optimum selection of raw materials to meet the application requirements. There is a large variety of resin type and glass fiber type available on the market that all have their specific strengths and weaknesses like maximum operating temperature, chemical resistance, mechanical stiffness and mechanical strength. The envisaged application area therefore often dictates the selection of the raw materials.

Fiberglass material 

In spite of standardization, most pipe manufacturers have their own proprietary joint systems. Over the last 30 years we have designed systems with pipes supplied by various manufacturers like National Oilwell Varco (Ameron, Centron, Star), Future Pipe Industries, Amiantit, Sarplast, Plasticon, CPI. We are familiar with their specific pipe and components catalogue and can help you to specify and select properly qualified materials.
For the joints, both mechanical and adhesive bonded systems are available. Adhesive bonded systems require special attention in hot climates like the Middle East as e.g. the pot life will vary with temperature. Total working time to complete a joint depends also on diameter of the pipe to be jointed.

Product Qualification Testing

Most of the FRP-related codes are performance-based codes that require proof of the strength of the final component. The capability of components needs to be proven with the use of pressure testing. The objective of the qualification procedure is to verify the proposed qualified pressure of each component.
For large diameter components the costs of qualification can be reduced by performing FEA (Finite Element Analysis). To get accurate FEA-results an FEA of a benchmark qualification test is performed to determine acceptable material stresses and strain. A modified but similar geometry can then be accurately optimized using FEA-tools such as FE/Pipe, Creo or Ansys. This optimization using software reduces the amount of failed qualification tests and thus the cost for the qualification.