Energy-saving and environment-friendly curtain wall glass becomes protagonist

People in the industry all know that the application of the building curtain wall in China began in 1984. After nearly two decades of development, the annual production and ownership of building curtain walls in China have ranked first in the world. However, in recent years, with the intensified competition, the saturation of the market, the decline in prices, and the reduction in profits, all people involved in the curtain wall industry are pondering: What kind of curtain wall is needed in the market? The author believes that energy-saving and environmentally friendly curtain wall products - vacuum glass for curtain wall will be the darling of the future market.

With the frequent occurrence of energy crisis, the deterioration of the living environment has made humans deeply realize the importance of energy conservation and environmental protection. According to the requirements of China's building energy conservation and environmental protection policy, before the year 2000, the newly designed heating residential building should be reduced by 50% on the basis of energy consumption in 1980 and 1981; from 2005 onwards, the newly-built heating residential building should be energy-saving on this basis. 30%; based on this in 2010, it will save 30% energy. According to this requirement of the country, it is predicted that the energy-saving and environment-friendly curtain wall products will have a promising market.

Some of the energy conservation and environmental protection measures currently used in the design and application of building curtain walls include:

(a) Insulating glass, especially LOW-E insulating glass technology.

Ordinary white glass 6mm, k value is about 5w/? k; 5 + 6 + 5 ordinary insulating glass, K value of about 2.6 ~ 3.5w /? k; If you use LOW-E hollow glass and charge argon, K value up to 1.6 ~ 1.8w /? K.LOW-E insulating glass has obvious energy-saving and environmental protection effects. In winter, it can effectively prevent the heat radiation of indoor heating from leaking out; in summer, it can prevent the heat radiation from outside from entering the room. The average annual usage of Low-E glass in the world has reached 120 million m3.

(B) "Insulation break bridge" technology

At present, China has introduced two kinds of production technology and complete set of special equipments, namely the “Injection-injection heat-insulating aluminum profile” and the “striped-fabrication-cut aluminum profile”. Over 100 heat-dissipating aluminum profile production lines have been built in Shenzhen, Nanhai, Foshan, Xi’an, Qinhuangdao and Beijing, with an annual production capacity of 1 million tons. In terms of market demand, the market share of insulated aluminum doors and windows continues to increase in these two years. According to statistics, for the current Beijing commercial housing project, the actual installation utilization rate of heat-insulating aluminum doors and windows has approached 46%, and this figure has exceeded 70% in the housing construction projects within the Fifth Ring Road in Beijing.

(III) Double-layer energy-saving curtain wall

The double-layer energy-saving glass curtain wall is mainly divided into internal circulation and external circulation systems, which have similarities and differences. The common feature is the formation of a greenhouse effect between double-glazed windows, and the summer overheated air in greenhouses is excluded from the outdoors. The solar thermal energy has been hung out of the room, so that a large amount of energy is available in the winter and summer seasons. In summer, it is necessary to protect the sun from UV rays and strong heat radiation. The internal circulation and external circulation systems have the following characteristics:

1. The main features of the inner loop double glass curtain wall structure

(1) The structural design can use the framework of heat or unit heat insulation.

(2) In general, the outer glass is made of hollow steel, and the inner glass is made of single steel.

(3) Compulsory measures shall be adopted to electrically control the pipeline system so as to exclude most of the hot air from the double-enclosed hot aisle during the daytime in summer. In the winter, the greenhouse effect heat is saved by opening the inside opening window or opening the door to discharge the hot air to the room to achieve the energy saving effect.

(4) The cavity thickness between the inner and outer layers is designed to be within 150-200mm

(5) It is necessary to add natural air into the sash passage in the room.

(6) It is easy to clean the dust between double glass.

(7) Use less material, so the cost is lower.

(8) However, it is necessary to use electric power to drive ventilation. It has a lower energy efficiency than the external circulation structure.

2. The main features of the external circulation double glass curtain wall structure

(1) The structural design can adopt several structural forms such as outer frame, unit or point docking, and the inner frame can be insulated from heat or the unit hollow glass can be insulated.

(2) In general, the outer glass is made of monolithic or laminated steel, and the inner glass is hollow or LOW-E tempered glass is selected.

(3) The natural "pipe flue" effect ventilation is adopted, and all dual-channel cabinets are independently sealed. During the summer season, the hot air in the greenhouse is excluded from the outside, and attention is paid to the effect of the “pipe” on different floors.

(4) The thickness of the cavity between the inner and outer layers is designed to be thick, which facilitates the entry of the cavity personnel between the inner and outer layers (450 mm).

(5) There is no need to add special equipment for natural air to enter the channel and the house. The outer curtain wall is designed with inlet and outlet. The inner curtain wall is designed to open the door or window. It should be noted that the inlet and outlet should prevent dust from entering, and the lower part of the channel should be set outside. The air enters the air inlet of the cavity and the exhaust air outlet after the upper heat exchange.

(6) Dust between double glass should be considered for easy cleaning.

(7) The use of materials is more, so the cost is higher. The estimated design material cost for this project is 2500 yuan/m2.