Acoustic jacketing are especially designed to guarantee best performance of acoustic insulation in applications such as suction chimneys for exhaust pipes or suction chimneys in combined cycle turbo gas powers plants , jacketing for insulation are assembled with glass cloth of different thickness and closed with Velcro or steel springs . They are used for thermal insulation of high temperature machineries in industrial, chemical and petrochemical sector where they enable to spare big energy costs. They can be removed to easily inspect or maintenance.