In building HVAC, water supply and drainage, and industrial equipment insulation systems, rubber and plastic insulation materials are widely used in hot and cold water pipes, air conditioning systems, and related equipment due to their closed-cell structure, ease of construction, and stable overall performance. While rubber and plastic materials appear to be highly versatile, their selection criteria vary significantly under different engineering conditions. This article analyzes the key technical factors in selecting rubber and plastic insulation materials from an engineering application perspective.

First, the operating environment and conditions must be clearly defined. Rubber and plastic materials can be used for both thermal and cold insulation, and different application scenarios require different temperature ranges and material structures. When used near high-temperature hot water or steam, long-term heat resistance should be a primary concern; in air conditioning chilled water or refrigerant pipes, low-temperature flexibility and anti-condensation capabilities are crucial. Engineering selection should be based on the design temperature range to avoid performance degradation during actual operation.

Second, the matching of thermal conductivity and thickness design is essential. While the thermal conductivity of rubber and plastic materials is relatively stable, the final system performance depends on the appropriate thickness selection. When selecting materials, the appropriate thickness should be determined by combining energy-saving design standards and thermal calculation results, while meeting the heat transfer coefficient requirements, rather than simply using empirical values. Insufficient thickness can easily lead to increased energy consumption, while excessive thickness may increase costs and construction difficulty.

The third key point is the closed-cell ratio and moisture-proof performance. Rubber and plastic materials rely on a high closed-cell ratio to achieve good water vapor permeability, which is their core advantage in preventing condensation in cold insulation systems. When selecting materials, attention should be paid to indicators such as water absorption rate and moisture permeability coefficient, and judgment should be made in conjunction with the humidity level of the project environment. In high humidity or outdoor environments, rubber and plastic products with stable closed-cell structures and good aging resistance should be given priority.

The fourth is the flame retardant performance and safety requirements of the materials. Rubber and plastic are polymer materials, and their flame retardant rating is directly related to the fire safety of the system. In public buildings and densely populated areas, the selection of materials should strictly follow relevant specifications, selecting products with clear flame retardant ratings and test reports, and paying attention to smoke density and drip characteristics during combustion to ensure the overall safety of the system.

Fifth, construction conditions and system compatibility need to be comprehensively considered. The flexibility and cutability of rubber and plastic materials are beneficial for complex pipeline construction, but different brands and formulations vary in resilience and adhesive compatibility. When selecting materials for a project, attention should be paid to the compatibility between the material and adhesives, protective layers, and outer packaging systems to reduce construction risks and improve system durability.

Finally, material quality stability and supply assurance are equally important. Rubber and plastic projects are often systemic applications, and repair costs can be high if quality problems arise later. Choosing suppliers with a sound quality control system, stable supply capabilities, and engineering service experience helps reduce project risks and ensure on-time delivery and long-term operation.

In general, selecting rubber and plastic materials for engineering projects is not a comparison of a single indicator, but a comprehensive judgment based on operating conditions, thermal performance, moisture and fire resistance requirements, and construction adaptability. Only through a scientific and standardized selection approach can the application value of rubber and plastic materials in building and industrial insulation systems be fully realized, achieving a balance between energy saving, safety, and durability.