Industrial and hydrocarbon infrastructure are prone to degradation(s) from corrosion and environmentally assisted cracking. Thermally insulated systems (pipelines, equipment, etc.) are often challenged by the trapped moisture underneath that leads to inevitable corrosion under insulation (CUI) and insulation-driven stress corrosion cracking (SCC). There have been advents in the industry for managing CUI using new hydrophobic insulation materials as well as contact-free systems. These options are recognised in the various industry standards for CUI, namely AMPP SP0198, API 583, and NORSOK. In addition to managing CUI and thermal losses, a key to sustainable thermal insulations is their impact on the surroundings. For example, additional resources are required to handle space constraints, weight limitations, and noise attenuation. These factors (space, weight, noise, etc.) are quite crucial when it comes to the offshore platforms where space, weight, and safe working conditions (i.e., hearing protection) are paramount. There are numerous studies published by researchers that talk about the impact of contact-free insulation systems and hydrophobic insulations from the standpoints of CUI and thermal conservation. Generally, the mass loaded systems with fibrous insulation systems that are effective in sound attenuation are not optimal for thermal insulation or for CUI prevention, and there has been no reported work that addresses the interaction of the contact-free and hydrophobic insulation designs recommended for CUI prevention from an acoustics standpoint. This presentation reports the R&D framework to understand the impact of industry-recommendations for CUI prevention, namely hydrophobic blanket insulation and contact-free insulation design, in combination with mass loaded vinyl for sound attenuation, for an assessment of overall acoustic system performance. The testing was conducted in accordance with ISO 15665 standard to understand the insertion losses at different frequencies. The testing revealed some interesting trends of noise attenuation, as the effects of contact-free insulation design in terms of sound attenuation were pronounced only for class C2 and D2 that calls for higher insertion losses (than class A2 and B2). While this work helps understand interaction of contact-free insulation and hydrophobic blanket in reaching the thinnest combination for noise attenuation (so far), the next phase of work involves using computational modelling and deploying a variety of different system configurations.
