Sunrain-Compatible 58/47 Silicone Sealing Rings for Solar Tubes | Dustproof, Waterproof, High-Temperature & Corrosion Resistant

I. Raw Material Specification

The core raw material of this solar vacuum tube dust-proof ring is 50° food-grade / industrial-grade silicone rubber (Shore A hardness 50°). It is a dedicated elastic material suitable for the outdoor operating conditions of solar energy systems, with properties fully meeting the application requirements for dust-proof sealing of vacuum tubes.

• Hardness CompatibilityThe 50° silicone rubber features balanced hardness, combining excellent elasticity and supportive strength. It avoids difficult installation and dust leakage caused by overly high hardness, as well as permanent compression deformation and collapse failure resulting from excessively low hardness. It is perfectly compatible with the two mainstream solar vacuum tube diameters: 47 mm and 58 mm, forming a tight seal between the tube body and the tank socket gap.
• Excellent Weather ResistanceFormulated with a special recipe, the raw material delivers outstanding UV resistance, anti-ageing performance, and resistance to extreme temperatures. It operates stably outdoors under temperature fluctuations ranging from -40°C to 120°C. Resistant to cracking under intense summer sunlight and winter freezing, it seldom suffers ageing defects such as yellowing, hardening, cracking or pulverization, boasting a far longer service life than ordinary rubber materials.
• Superior Dustproof & Sealing PerformanceSilicone rubber features inherent flexibility and sealing capability, providing remarkable protection against dust, water and wind-blown sand. It effectively blocks outdoor dust, catkins, rainwater, mosquitoes and other contaminants from entering the joint between the vacuum tube and the water tank. In addition, the material is non-toxic, odourless, environmentally friendly and corrosion-resistant. It withstands acid-alkali erosion from rainwater and oxidative corrosion, making it ideal for long-term outdoor exposed service.
• High Physical StabilityThe raw material possesses high toughness, tensile strength and puncture resistance. It resists deformation or breakage during installation and removal. It maintains consistent elastic sealing performance under prolonged cyclic temperature variations and is not prone to loosening or displacement.

II. Raw Material Performance Parameters

III. Production Process (Compression Molding via Vulcanizing Machine)

This product is manufactured by high-temperature compression molding with professional vulcanizing machines under full standardized production. It features high dimensional precision, consistent quality and stable structure. Different from conventional injection molding and extrusion processes, this technology perfectly meets the structural sealing requirements of dust-proof rings.

• Raw Material PretreatmentWe select premium virgin 50° silicone rubber, strictly filter out impurities and carry out mixing & milling procedures to evenly adjust material hardness and toughness. This guarantees consistent performance across all batches and prevents quality defects caused by adulterants or recycled materials.
• Precision Mold PositioningCustom molds are developed for 47 mm and 58 mm vacuum tube specifications. High-precision shaping molds are adopted with extremely tight dimensional tolerances, ensuring the inner bore, outer diameter and thickness accurately fit the two types of vacuum tubes.
• High-temperature Vulcanization & Compression MoldingPretreated silicone material is loaded into dedicated molds on the vulcanizing machine and formed in one step via high-temperature and high-pressure vulcanization. Vulcanization stabilizes and cures silicone molecular structures, greatly improving the product’s wear resistance, anti-aging property and structural compactness. Finished products are free of air bubbles and burrs with uniform texture.
• Deflashing & Quality InspectionFormed dust-proof rings undergo precision deflashing by manual work and machinery to remove excess flash, ensuring smooth edges and excellent fitting performance. Strict dimensional inspection, elasticity testing and visual screening follow afterwards to eliminate defective products, so all delivered goods feature unified specifications and qualified performance.
• Core Advantages of the ProcessCompression vulcanization molding delivers denser product structure and superior elastic recovery. Products resist deformation and shrinkage during long-term service, maintaining stable sealing and dustproof performance. With good wear and tear resistance, they are suitable for long-term, frequent outdoor working conditions.

IV. Application Scenarios

This 47/58 mm silicone dust-proof ring is a dedicated accessory for vacuum tubes of solar water heaters. It is specially designed to match residential and commercial solar thermal collection equipment, featuring a wide range of applications and excellent practicality.

Residential Solar Water Heaters

It fits most integrated household solar water heaters used in urban and rural areas. Developed for mainstream 47 mm and 58 mm glass vacuum tubes available on the market, it is mounted at the socket where the vacuum tube inserts into the water tank to fill the gap between the tube and the tank inner liner. It delivers dustproof, waterproof, insect-proof and wind-sand resistant performance, preventing dust and debris from entering the tank to contaminate water quality or block pipelines. Meanwhile, it avoids accumulation of mosquitoes and flocculent substances that would impair heat dissipation and shorten the service life of equipment.

Commercial Solar Thermal Projects

Compatible with large centralized solar heat collection systems in factories, hotels, schools, homestays, construction sites and other locations, and used together with 47/58 mm vacuum tube collectors. Under open-air outdoor installation conditions, it effectively resists erosion from harsh weather such as wind, sand, rain, snow and intense sunlight. It protects the connection between the tank socket and vacuum tube, reduces equipment failures and lowers subsequent maintenance costs.

Maintenance & Replacement of Solar Equipment

As a wearable replacement part for solar water heaters, it can replace aged, hardened, cracked or detached old dust-proof rings. It is compatible with vacuum tube solar equipment of various common brands and models. Featuring easy installation and high versatility, it quickly restores the sealing and dustproof performance of equipment and extends the overall service life of solar water heaters.

Special Open-air Solar Thermal Equipment

Suitable for various small solar heat collection devices installed openly in courtyards, rooftops and field environments. Taking advantage of silicone’s weather resistance, wide temperature resistance and anti-aging properties, it adapts to harsh outdoor operating conditions with full exposure, strong sunlight and drastic temperature fluctuations, and continuously ensures sealing protection at equipment connections.