The storage and transportation of cryogenic media such as LNG, methanol or ethylene demand high-per¬formance insulation materials. With Armaflex Cryogenic Systems, Armacell is now the first supplier to present flexible insulation products which have been specially developed for low-temperature applications. The multi-lay¬ered systems ensure exceptional thermal insulation, reduce the risk of cor¬rosion under insulation (CUI) and allow consider¬able cost savings during the installation process. The insula¬tion systems are ‘patent pending’.
Flexible at cryogenic temperatures
Armaflex Cryogenic Systems provide in a single material the key performance qualities required for insulation materials in low-temperature environments. These could previously only be achieved through a combination of several differ¬ent materials (for example, rigid foams with separate vapour retarders and con¬traction joints).
The new cryogenic foams have low thermal conductivity and re¬tain their flexibility even at low temperatures. Due to this flexibility, vibrations and impact are absorbed and the risk of cracking as a result of extreme tempera¬ture cycles or external mechanical strain is reduced dramatically. An important advantage of Armaflex Cryogenic Systems is the fact that they need neither additional expansion joints nor vapour barriers.
Built-in expansion joint
Because of the low-temperature flexibility of the material, the system itself acts as a contraction and ex¬pansion joint. Thus the pipe is protected against thermal stress and crack formation. Traditional systems made of rigid foam utilise glass wool or mineral fibre as a buffer against contraction and expansion. This not only increases the installation costs; due to the open-cell material structure of the expansion joints, the risk of moisture infil¬trating the system and compromising the insulation effect rises.
Built-in vapour barrier
Moreover, Armaflex Cryogenic Systems do not need additional vapour barriers. Armaflex is a closed-cell material with a high resistance to water vapour trans¬mission and as such has a ‘built-in’ vapour bar¬rier. Unlike traditional systems where each insulation layer must be protected against moisture infiltration by a separate vapour barrier, in the case of Armaflex the resistance to water vapour transmission is built up throughout the entire thickness of the insulation. This not only increases the reliability of the insulation system, but also reduces the in¬stal¬lation costs significantly as there is no need for the time-consuming process of in¬stalling vapour barriers with sealants and special adhesive tapes.
Field of application
Armaflex Cryogenic Systems can be used in the temperature range of -200° to +125°C. The inner system layer made of Armaflex LTD is a specially developed diene ter¬polymer which prevents thermal stress. The outer layers consist of Armaflex, the world’s leading flexible insulation mate¬rial.
With its closed-microcell structure, low thermal conductivity and high resistance to water vapour transmis¬sion this material provides in¬stallations with long-term protection against moisture infiltration and energy losses. The metal cladding ensures high resis¬tance to mechanical impact. At application tempera¬tures below -110°C, the system is completed by the Armaflex LTD anti-abrasive foil, which provides the inner insu¬lation layer with added surface strength. If noise control is also required on the cryogenic pipework, the combined use of Armacell’s acoustic insulation mate¬rials ArmaSound Industrial Systems is recommended. The systems are coordi¬nated with each other and meet the thermal-acoustic requirements with signifi¬cantly reduced insulation thickness and weight compared to traditional insulation systems.
Due to their high flexibility, Armaflex Cryogenic Systems are much easier and quicker to install than rigid materials and a good fit can be achieved even on awkwardly shaped in¬stallations.
Armaflex Cryogenic Systems are specially designed for use on pipelines, tanks and pro¬duction equipment in the oil, gas and chemical industries. They are also par¬ticularly suit¬able for insulating liquefied natural gas (LNG) installations. The new insulation systems have been specified for ventures operated by some of the leading international oil and gas companies and are currently being installed in the Dalian LNG terminal (China).
Over the past years, in cooperation with the University of Southampton, Armacell has carried out extensive research into the behaviour of elastomeric insulation materials at cryogenic temperatures. Armacell now has knowledge of this special field of application which is unique in its industry.