Protection against Corrosion

Guaranteed rust-free

Rust can cause severe damage to technical plants and pipe systems. Therefore, long-term protection should always be used at the time of insulation. Although some plant parts are less susceptible to corrosion, reactions of metals under the influence of moisture cannot be entirely avoided. In damp environments, in particular, additional protective measures are indispensable. Without sufficient insulation, corrosion can also be the consequence of condensation.

Insulation with FEF and PEF reduces the risk of condensation reliably: It keeps surfaces dry and protects it against corrosion.

Exterior danger zones

Interior walls of pipes and tanks are better protected from corrosion than their exterior, because there is usually no oxygen in closed systems. It behaves differently with exterior surfaces: The composition of the moisture which influences the medium from outside is normally unknown. For instance, water with a low pH value (<7) promotes greater corrosion. In addition, oxygen cannot be kept away from the surfaces altogether. Exterior corrosion is also the most frequent cause for moisture damage on pipelines and other installation systems.

Prevention of localised corrosion

When there is surface corrosion, the material decomposes successively and consistently. Selective corrosion, on the other hand, only appears in limited areas and advances rapidly. It can lead to so-called stress fracture corrosion, which arises with the combination of corrosion and tension stress. The effect also referred to as 'pitting' arises when concentrations of certain chemical substances influence the surface. Non-rusting steel, for instance, can become susceptible to corrosion when coming into contact with chlorides. Therefore, corrosive contents in insulting materials may not exceed certain thresholds. The extent to which metal materials can be used under critical conditions can normally be determined by referring to the manufacturer resistance charts.

Types of corrosion

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In general, there are two different processes of corrosion: With chemical corrosion the metal oxidised due to the reaction with oxygen. With galvanic corrosion the process takes place between two metals, wherein the lower-grade metal usually sustains the greater decomposition. This effect can occur in installation technology when different metal types are installed together. In both cases, moisture triggers the process. Technical insulation can prevent such processes in advance by keeping the surface and surroundings of the medium to be protected dry.

Taking protective measures

It must be ensured on site that pipes and tanks do not come into long-term contact with moisture. Close-cell insulation has a proven track record in this connection. They prevent the penetration of moisture to the surface of the medium. For this purpose, their application must be water-tight and they must be precisely adhered at joints. Metal surfaces can also be provided with effective anti-corrosion protection in the form of a primer or coating. Many members of CEFEP offer appropriate system supplements for this.