With the continuous improvement of people’s living standards, the requirements for residential doors and windows are also increasing. In addition to safety and comfort, the quality and individuality of doors and windows are also required, and environmental protection and energy conservation are required. This raises higher requirements for building materials for doors and windows, and the emergence of "second generation aluminum alloy door and window building materials" has solved the problem. According to the "10th Five-Year Plan" and the 2010 development plan, the relevant departments predict that in the first ten years of this century, China will build 5 billion square meters of residential houses for villages and towns, build 1 billion square meters of public buildings, and build urban housing in 10 years. The construction volume is 3.35 billion square meters. Such a huge construction market requires a large number of doors and windows. If the window area is calculated on the basis of 15% of the building area, the area of ​​the door is calculated on the basis of 11% of the building area. The annual average demand for windows is 200 million square meters. The doors are 147 million square meters. With the development of the construction market, relevant departments have proposed a 50% target for building energy efficiency. From October 1, 2003, the industry standard “Energy-saving Design Standards for Residential Buildings in Hot Summer and Warm Winter Regions†issued by the Ministry of Construction was formally implemented. The introduction of the Standards means that the future residences should consider energy conservation issues from the time of design. . Therefore, domestic door and window manufacturers have taken the development of new energy-saving doors and windows as the main way to achieve energy conservation. Energy-saving doors and windows mainly through the two parts of the frame and glass, the structural performance of the transformation, to prevent the three forms of heat loss. Among them, the “cold-aluminum cold-bridge profiles†in the “second-generation aluminum alloy building materials†are excellent products in environmental protection and energy-saving building materials.
There are two forms: "Tip process" and "Pouring process"
"Trip strip craft" is to connect two parts inside and outside the aluminum profile by two heat insulation strips, so as to prevent the conduction of heat inside and outside the aluminum profile and achieve energy saving. It is a technology from Europe, and it is more common in the market. According to incomplete statistical data, there are nearly 100 companies that use imported wear strip production equipment and domestic wear strip production equipment, and less than half of the total number of normal production.
The “pouring process†technology for heat insulation and energy conservation originated in the United States. In October 1937, a patent describing how aluminum alloy materials were insulated was born. Its main idea is to inject a mixture of sealing wax into the middle of aluminum for doors and windows for thermal insulation. At the same time, patents on polyurethanes appeared in Germany. In 1952, another patent was released publicly. The idea of ​​the inventor of this patent is to fix an unmolded polymeric insulating polymer in a heat-insulating groove dedicated to an aluminum alloy profile by bonding or mechanical force. Then, as we have seen today, cutting off the joints at the bottom of the aluminum alloy profile is a prototype of today's "pouring process" technology. At present, many domestic manufacturers have introduced casting equipment, including imported and domestic ones, and most of these manufacturers have introduced pouring equipment while they are wearing strips.
A. "Twisting" VS "Casting" Process Comparison
(1) Production process
Wearing aluminum heat insulation strips generally separate teeth, wear strips, rolling three processes, and now there are equipment manufacturers to open teeth and wear strips on a device to complete, known as the "two-step method."
Open teeth: Use a device with a hard roller gear to roll out the part of the aluminum profile that is going to wear the insulation bar out of the tooth. The purpose is to increase the roughness of the profile by hobbing so as to increase the shear force of the profile after assembly. As the profile is divided into two parts inside and outside, according to the needs of production, the opening device is generally two.
Wearing strips: It is to put the insulation strips on the profiles, and connect the inner and outer profiles to prepare for the next roll. One device can be.
Rolling: This process is divided into three steps: guiding and pre-clamping, main clamping, and straightening (horizontal direction, vertical direction), which is the key to ensure the tightness and verticality of the finished profile.
(2) Production process
The "casting process" is to move the surface-treated aluminum profile through a linear motion of the walking system so that when the thermal insulation groove of the aluminum profile passes under the pouring head of the casting machine, the liquid heat insulation material flows into the insulation groove, and after a period of time After solidification, cut the bridge.
Second, insulation material
(1) The heat-insulating material of the “striping process†is a heat-insulating strip. At present, the regular heat-insulating strip is polyamide 66 (namely, Polyamide 66, commonly known as nylon 66). There are two production methods: hard-top method and traction method. . The hard-top method has a tight structure and a good appearance but is relatively "brittle." The toughness produced by the traction method is good but the appearance is poor, and the side has a process depression. In order to pursue the appearance of beauty and precision, using PA66 nylon plus ultra-fine glass fiber is a common feature of foreign insulation bars (rarely use other materials). Due to the use of ultrafine glass fiber, the tensile strength is only 60N/mm, and it is expensive. Take Tylenol Pautai's 926900 (I12) as an example, one meter is about 2.5 yuan, and one ton is about 24,000 meters. The cost of thermal insulation strips used on one profile (6 meters) is about 30 yuan. Therefore, the domestic PA66 plus ordinary glass fiber as the main direction of attack has achieved certain breakthroughs. However, some people have used PA6, ABS (styrene-acrylonitrile-butadiene-copolymer terpolymer), PP (polypropylene), and even some of the relevant national departments such as PVC have explicitly stipulated that they are not allowed to use only as non-structural General plastic materials used to replace engineering plastics PA 66 to make heat insulation strips, and some used to seriously affect the environmental protection of mineral fibers and stone powder. Shoddy. Seriously affected the market, resulting in vicious competition in the market, making the development of wear strip technology in the country has been affected.
(2) The current insulation material of the "pouring process" is mainly polyurethane heat-insulating adhesive. Its composition is generally composed of a resin component and an isocyanate component. It is divided into two major categories, both foreign and domestic, of which the representative is Yasong of the United States. It has been engaged in this work for a long period of time, and its performance is relatively perfect. However, due to the production of raw materials in the United States or South Korea, its cost has increased. The price is also high. A ton of more than 40,000, domestic manufacturers of such insulation rubber is less, the current better is the solid polyurethane development company in Dalian, its product performance and import of no difference, but the price is higher than the import Much lower, one ton is around 24,000. Due to the relatively small number of manufacturers of such insulation materials and the orderly competition in the market, they are not as chaotic as the “wrap-in-the-art†insulation bars.
Third, equipment
(1) The wearing equipment is divided into two kinds of imported equipment and domestic equipment. Imported equipment is generally from Germany or Switzerland, of which Swiss Muller, for example, a set of equipment including open gear, threading machine, rolling machine and testing machine, the overall set of at least about 800,000. There are many manufacturers of domestic equipment, and the price is not very standard, roughly between 20 to 50 million.
(2) The "pouring process" is a technology that is inseparable from equipment and glue. Therefore, the manufacturers of equipment and insulation rubber are basically the same. The import is mainly ASSOL, and the equipment is shipped to the United States for domestic production. It is relatively high, with Class I at about 1.4 million and Class II at about 700,000. The mixing ratio of the two raw materials is fixed so that the manufacturer must use its raw materials, otherwise it cannot work and has poor generality. Domestic equipment, Dalian Lianshi Technology Co., Ltd. produced equipment on the basis of the same basic principles, made a major change, the more critical point is that all actions are controlled by the computer, the ratio, temperature can be adjusted according to need. With the initiative, users can choose more suitable raw material suppliers. The price is generally between 300,000 and 400,000.
Four, off heat profiles
Polyurethane cast aluminum, wear strip aluminum. Composite profile strength: Aluminium profiles are extruded at one time, which reduces process defects. Polyurethanes are poured into aluminum profile insulation tanks at one time to form a polyurethane heat-insulating bridge. Due to the high adhesiveness of polyurethane, heat-insulating bridges and aluminum profiles are completely To be one, so the strength of aluminum is high. After the aluminum profile is extruded twice, the heat insulation strip is put into the process slot of two aluminum profiles. After the rolling process, the strength of the heat insulation material cannot be very high. , otherwise it will break and produce waste. The intensity should not be high. Profile cross-sectional area: compact structure, small and beautiful to go through the opening, rolling process, large cross-section. Thermal expansion coefficient: Compared with aluminum profiles. Plasticity: It can be made into a variety of special-shaped doors and windows, including a circular arc window with a smaller diameter 360. Due to the mechanical connection between the insulating strip and the aluminum profile, when the aluminum profile is greatly deformed, the heat insulating strip easily escapes from the connecting groove of the aluminum profile, so that its window shape is limited.
The production of windows and doors of the light barrier: small and handsome appearance.
Fifth, the cost of aluminum profiles
Aluminium is 20,000 yuan/ton, PVC insulation is 8,000 yuan/ton, PA66 insulation is 30,000 yuan/ton, polyurethane casting rubber is 24,000 yuan/ton.
The density of aluminum is 2.7g/cm3. The density of PVC is 1.4g/cm3. The density of PA66 is 1.3g/cm3. The density of polyurethane is 1.2g/cm3. The width of the casting cavity is generally 0.8cm less than the width of the pass-through cavity, and the general inner and outer wall thickness is 0.15. Cm, the thickness in the middle is 0.12 cm. Profile length is calculated as 600cm.
1. The cost savings for each type of cast aluminum bar over the strip type are:
Each aluminum saves weight: 0.8cm×(0.15+0.12+0.12+0.15)×600cm×2.7g/cm3=699.9g=0.7kg
Each saves aluminum cost: 0.7kg×20yuan/kg=14yuan/root
2. The wear rate is:
Strip thickness is 0.2cm, strip width is 1.5cm, length is 600cm
The amount of PVC strips per aluminum: (0.2×1.5) ×2×600×1.4g/cm3=504g=0.5kg
The cost of each aluminum PVC strip is 0.5kg×8.00yuan/kg=4.00yuan/each aluminum PA66 stripper amount:(0.2×1.5)×2×600×1.3g/cm3=468g=0.47kg
PA66 wearing cost per aluminum: 0.47kg × 30 yuan / kg = 14.1 yuan / root
3. The amount of polyurethane is:
The amount of polyurethane for each aluminum profile: 1.1cm × 0.8cm × 1.2g/cm3 × 600cm / root = 633.6g = 0.6336kg / root
The cost of each aluminum profile polyurethane: 0.6336kg/root×24yuan/kg=15.2064yuan/root
4. Cast aluminum profiles save more than PVC strips:
14 yuan/root?(15.2064 yuan/root?4.00 yuan/root)=2.7936 yuan/root
5. Cast aluminum profiles save more than nylon 66
14 yuan/root?(15.2064 yuan/root?14.1 yuan/root)=12.8936 yuan/root
Sixth, summary:
Both the “wearing strip process†and the “pouring process†have good thermal insulation properties and are the development direction of energy-saving aluminum alloy building materials. The country has also clearly pointed out the necessity of developing cold bridges. The national quality inspection department also conducts special rectifications on the building materials market, severely investigates and punishes illegal activities in the production and sale of building materials, including production and sales of products that do not meet national or industrial standards or are explicitly prohibited from being eliminated. The national standard for aluminum alloy heat insulation building profiles will be introduced this year. The market for thermal insulation and energy-saving profiles will become clearer by then.