Water. Desalination + reuse
Issue link: https://fhpublishing.uberflip.com/i/670678
| 22 | Desalination & Water Reuse | May-June 2016 TECHNOLOGY Pressure PiPing systems that transport a wide range of dangerous and non-dangerous liquids and gases in European installations must meet the essential safety requirements laid out in the Pressure Equipment Directive (PED 97/23/EC). This soon to be updated legislation establishes consistent safety practices in pressure equipment and related piping system design, operation, and maintenance. Those who commonly use the directive and its various annexes have come to rely on these guiding principles in the preparation of their conformity assessments, technical construction files (TCF's), Declarations of Conformity, and application of the "CE" mark. In relation to mechanical piping systems and their components, this directive is often misinterpreted or misunderstood. For example, many system designers expect that mechanical piping products follow some type of pressure rating protocol based on the system temperature or that a mechanical coupling is considered pressure equipment. Another misconception is that these types of products require a "CE" mark and must be accompanied by a Declaration of Conformity in order to be considered compliant with the directive. The following pages address such topics and outline a best-practices approach to PED-compliance when using mechanical couplings and fittings to join grooved end piping systems. Product classification within the Ped Mechanical couplings and fittings for grooved end piping systems do not meet the definition of pressure equipment or pressure accessories as defined in the PED and other industry-accepted PED guidelines. By themselves, these material components do not contain a specifically defined pressure boundary and primarily serve to connect two grooved pipe ends, grooved end fittings, or other grooved end components within a pressure system. Therefore, in order to maintain compliance with the directive, these components are not "CE" marked, and do not require a PED Declaration of Conformity. Because of some misunderstanding in regard to these requirements, system owners may be mistakenly presented with products bearing the "CE" mark accompanied with dossier packages containing declarations or conformity statements that are simply not valid for these types of products. This can result in further confusion between notified bodies and their clients as they strive to complete their pressure equipment installation review and related safety inspections in time to meet system commissioning schedules. However in contrast, when pressure equipment or a pressure piping system is fully constructed using mechanical couplings and fittings, this entity that functions as a pressure retaining unit does qualify for testing and certification for "CE" marking by the end user under the control of their Notified Body. This is also a clear requirement for certain risk categories based on the system pressures, temperatures or fluid type and classification. Some applications here include high pressure filtration (reverse osmosis), concrete pumping, mining slurry systems, compressed air and hydraulic lifting systems - just to name a few. _________ len swantek Director, Global Regulatory Compliance at Victaulic ___ Mechanical Pipe Joints Perform Under Pressure Since their introduction nearly 100 years ago, mechanical grooved piping systems have provided a wide range of performance benefits for system designers, installers and end users. The application of these components in pressure piping systems under PED jurisdiction is supported by a thorough design validation program, combined with material and product testing to demanding norms and standards