Questions regarding the selection of gaskets for non-metallic pipelines
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Hello, all sea friends! Let’s discuss the issue of selecting non-metallic gaskets. In chlor-alkali plants, the non-metallic pipelines are mainly made of FRP, PVC, CPVC, or PVC/FRP. Design agencies generally recommend using RPTFE gaskets; however, due to their high hardness and low resilience, these gaskets cause the flanges to deform over time, and they are prone to leakage under the influence of temperature. For non-metallic pipelines that involve the use of hydrochloric acid and hydrogen chloride, we use EPDM; for those that involve the use of chlorine gas, chlorine water, and sodium hypochlorite, we use ePTFE. I would like to ask the experts how they make their choices?
Based on your description, the media used in non-metallic pipelines include hydrochloric acid, hydrogen chloride, chlorine gas, chlorine water, and sodium hypochlorite, among others. When selecting non-metallic gaskets, it is necessary to consider the properties of the medium, operating temperature, pressure, and other environmental factors. For acidic media such as hydrochloric acid and hydrogen chloride, common gasket materials are polyvinyl chloride (PVC) or chlorinated polyvinyl chloride (CPVC), which possess good acid resistance. For FRP (fiber-reinforced plastic) pipelines, compatible gasket materials can be selected. For chlorine-containing media such as chlorine gas, chlorinated water, and sodium hypochlorite, a commonly used gasket material is modified polytetrafluoroethylene (ePTFE). ePTFE gaskets possess good corrosion resistance and high-temperature resistance. RPTFE (reinforced polytetrafluoroethylene) gaskets are typically used in acidic and alkaline environments as well as under high-temperature conditions. However, due to their high hardness and low resilience, they may experience deformation and leakage over time. Therefore, when selecting gasket materials, it is necessary to take into account factors such as the properties of the medium and operating conditions; tests and evaluations can be carried out in actual engineering applications to choose the appropriate gasket material. It is best to contact professional design firms or suppliers, as they can provide more specific advice and solutions to meet your particular project requirements. .
How is the low-calcium-magnesium EPDM gasket suitable for use in high-purity hydrochloric acid pipelines?