1. Insulation Material Selection and Technical Requirements
Insulation materials for air-conditioning water pipes shall meet the requirements of GB/T 17794-2019 "Flexible Cellular Rubber and Plastic Thermal Insulation Products" and GB 50264-2013 "Code for Design of Thermal Insulation Engineering of Industrial Equipment and Pipelines." Commonly used insulation materials: NBR/PVC cellular rubber sponge with thermal conductivity ≤0.039 W/(m·K) at 0℃, applicable temperature range -40℃ to 105℃, moisture resistance factor ≥15,000; glass wool with thermal conductivity ≤0.037 W/(m·K) at 0℃ but requiring an additional vapor barrier; PEF polyethylene foam with thermal conductivity ≤0.038 W/(m·K).
2. Insulation Thickness Design and Condensation Prevention Verification
Insulation thickness shall be designed and calculated in accordance with GB 50264-2013 and shall simultaneously satisfy: economic thickness with investment payback period ≤5 years; condensation prevention thickness with surface temperature ≥ ambient air dew point temperature plus 1℃; maximum allowable heat loss meeting energy-saving standard requirements. Condensation prevention thickness calculation steps: determine environmental conditions temperature Ta=26℃, relative humidity RH=70%, dew point temperature Td=20.1℃; calculate insulation surface temperature Ts ≥ Td+1℃=21.1℃.
3. Insulation Construction Technology and Quality Control
Core construction technology requirements for insulation per GB 50264-2013 and CECS 125-2001: insulation construction shall be carried out after pipe pressure testing is qualified and rust removal and anti-corrosion are completed; insulation materials shall be kept dry during installation with moisture content ≤3%; longitudinal seams of pipe shells shall be staggered, seams bonded with special adhesive with glue application width ≥50 mm and open time 5-15 minutes; joints between pipe shells shall be sealed with special tape, aluminum foil tape or acrylic tape; removable parts such as valves, flanges and strainers shall use removable insulation boxes.
4. Condensation Prevention Inspection and Acceptance Standards
Condensation prevention inspection methods: visual inspection of insulation for damage, seam sealing and vapor barrier integrity; surface temperature measurement using infrared thermometer at 1 point per 10 meters, with additional measurements at key locations such as valves and fittings; dew point temperature verification—calculate dew point from ambient temperature and humidity; surface temperature must be ≥ dew point temperature plus 1℃; operational verification—after 24-48 hours of system operation under summer high-humidity conditions, check for absence of condensation.