Pipe Section - Properties Tab
There are two formats in which pipe section properties may be specified – the Standard format which references a Material component, or the Direct format, where structural properties such as bending and axial stiffnesses are explicitly specified without any reference to a material. You select the format you want to use from the Specification drop-down list as shown in the 'Format Selection' figure below. The remaining inputs on the Properties tab are enabled or disabled as appropriate, depending on the material format selected here.
The default option is Standard, and the required inputs in this format are illustrated in the figure below. Note that explicit specification of the Weight in air / UL, the Weight in water / UL and the Moment of Inertia of the pipe section is optional. If you do not specify these values, PipeLay automatically computes default values. For example, in the case of Weight in air / UL, PipeLay computes default values from properties associated with the Material you specify for the Pipe Section component as well as the various dimensions you define on the Pipe Section component itself. These calculated values appear on the component view enclosed in square brackets to indicate that they are not user inputs.
Material Properties in Standard Format
The Properties tab also contains External Coatings and Internal Coatings buttons, which you use to specify coatings on the pipe section. For example, the coatings can represent insulation material or marine fouling. Coatings may only be specified if the Standard format is used to specify the pipe section properties. All coatings are characterised in terms of thickness, mass density, and water absorption. The weight per unit length, contact diameter, drag diameter and buoyancy diameter of the pipe section are all modified to account for the presence of coatings. For an external coating, you can also specify two additional properties: a Material component and a Bond Bending Resistance. These properties augment the pipe stiffness behaviour to account for the stiffening effect of some coatings, such as concrete. Please refer to Technical Note 7 for more details on how the stiffness contribution of coatings is calculated.
The stiffening effect of external coatings is not captured in PipeLay Starter Edition
Several coatings may be associated with the same base section, in which case each coating is applied over the previous coating. The order of coatings is consistent with the order in which they appear in the External Coatings or Internal Coatings dialog. In other words, coating number one is closest to the pipe.
The alternative format for the definition of pipe section properties is Direct, and the required inputs in this format are illustrated in the 'Material Properties in Direct Format' figure below.
Material Properties in Direct Format