CSA Preface This is the first edition of IEEE Std 844.2™/CSA C293.2, Standard for Skin Effect Trace Heating of Pipelines, Vessels, Equipment, and Structures—Application Guide for Design, Installation, Testing, Commissioning, and Maintenance, which is a harmonized Standard jointly developed by IEEE and CSA Group. Skin effect trace heating systems have been used for a number of years in the industry. Skin effect trace heating of pipelines, vessels, equipment, and structures in petrochemical as well as other industries is a growing portion of total heating requirements because of its advantages in heating long pipelines with temperature control. This Standard should be used in conjunction with IEEE Std 844.1™/CSA C22.2 No. 293.1, Standard for Skin Effect Trace Heating of Pipelines, Vessels, Equipment, and Structures—General, Testing, Marking, and Documentation Requirements. Since skin effect trace heating systems are interrelated with electric power, control, and alarm systems, other standards, some of which are listed in Clause 2, should be referred to when using this Standard.
Overview 1.1 General This standard is divided into seven clauses. Clause 1 provides the scope and purpose. Clause 2 lists references to other standards that are useful in applying this standard. Clause 3 references definitions that are found in IEEE Std 844.1/CSA C22.2 No. 293.1. Clause 4 establishes the design guidelines for skin effect trace heating. Clause 5 provides installation considerations and guidelines. Clause 6 covers field testing, start-up, commissioning, and operation of skin effect trace heating systems. Clause 7 provides maintenance and repair guidelines. This standard also contains annexes. Annex A provides bibliographical references. Annex B provides pipe heat loss considerations. Annex C provides vessel heat loss considerations. Annex D covers heat-up and cool-down considerations. Annex E provides a method to determine equivalent thicknesses of insulating cements. Annex F provides an example of design input parameters for a skin effect trace heating design. Annex G presents an example of a record for installation requirements. Annex H shows an example of a form that can be used to document the commissioning of the system. Annex I presents an example of a preventive maintenance record. 1.2 Scope This standard provides for the application of skin effect trace heating systems for pipes, vessels, and structures. It provides recommendations for design, installation, maintenance, and repair of these systems in general industry for ordinary locations, as well as in hazardous areas with potentially explosive atmospheres. This standard, when used with other recognized codes and standards, is intended to cover skin effect trace heating systems in their entirety, including system design, specifications, installation, operation, testing, commissioning, and maintenance. This standard also addresses the following associated systems that are important to the performance of skin effect trace heating systems: a) Thermal insulation systems; b) Electric power supply systems; c) Electric grounding systems; and d) Control and monitoring systems. 1.3 Purpose This standard is intended to aid the user in specifying, installing, operating, testing during commissioning, and maintaining skin effect trace heating systems that a) Maintain design temperature; b) Provide electrical, thermal, and mechanical durability and reliability; and c) Reduce hazards to the user and the surroundings. Design information, selection parameters, and data in this standard are not intended to provide a complete design primer for skin effect trace heating systems. The information presented provides guidelines for - Selecting the optimum skin effect trace heating system design; - Establishing design criteria and constraints for the heated pipeline, vessels, or structures to ensure system compatibility; - Preparing specifications to obtain quotations for skin effect trace heating systems; and - Developing information on installation, operation, testing, commissioning, and maintenance of the skin effect trace heating system. 1.4 Terminology In this standard, "shall" is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; "should" is used to express a recommendation or that which is advised but not required; and "may" is used to express an option or that which is permissible within the limits of the standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.