The thermal insulation performance of aluminum alloy thermal insulation swing door may be affected by many factors in long-term use. These factors interact and gradually change the physical properties of the door structure, resulting in a decrease in thermal insulation effect. First of all, the material stability of the profile itself is the basic factor. Although aluminum alloy has high strength and corrosion resistance, its thermal conductivity is relatively high. Even if thermal insulation strips are used for bridge breaking treatment, when subjected to temperature difference changes for a long time, the junction between the thermal insulation strips and the aluminum alloy profiles may produce tiny gaps due to thermal expansion and contraction. In particular, nylon 66 thermal insulation strips, although they have good heat resistance, may age and crack after long-term use if the pressing process is not in place during installation, resulting in the re-penetration of the hot and cold bridges and weakening the thermal insulation performance.
The aging of the sealing strip is a key link affecting the thermal insulation performance. As a sealing barrier between the aluminum alloy thermal insulation swing door body and the door frame, the strip will oxidize, harden and shrink when exposed to the air for a long time. Rubber strips gradually lose their elasticity under ultraviolet radiation and temperature fluctuations, and gaps appear in the originally tightly fitting sealing structure, allowing the outside hot and cold air to penetrate. Especially under the frequent squeezing of opening and closing doors, the deformation fatigue of the rubber strip is aggravated, the edge may curl or break, forming an air convection channel, which reduces the air tightness of the door body and the insulation effect. In addition, if the matching degree between the rubber strip and the profile slot is hidden due to production errors or improper installation, it is more likely to fall off or shift after long-term use.
The performance stability of glass components plays a decisive role in the insulation effect, and the sealing performance of insulating glass is the key. In a high humidity environment for a long time, the molecular sieve desiccant of insulating glass may lose its moisture absorption capacity due to adsorption saturation, resulting in condensed water in the glass cavity, which not only affects the light transmittance, but also destroys the insulation effect of the vacuum layer. The sealant layer may crack or debond under the action of temperature difference cycle, and the outside air enters the hollow layer to form a heat conduction path, especially the structure with butyl glue and silicone glue composite sealing. If the compatibility of the two colloids is poor, the interface is easy to separate after long-term use, accelerating the performance failure. In addition, the PVB film of laminated glass may soften at high temperature and become brittle at low temperature, resulting in a decrease in the overall thermal stability of the glass.
The wear and aging of hardware accessories indirectly affect the thermal insulation performance. Although metal parts such as hinges and locks are not directly involved in the thermal insulation structure, they will cause the door body to sag or shift due to load-bearing wear after long-term use. When the parallelism between the door leaf and the door frame changes, the compression of the sealing strip is uneven, and the failure of the seal in the local area will form a leak point. For example, the wear of the hinge sleeve causes the door leaf to sink, the bottom rubber strip is over-pressed and ages prematurely, and the upper rubber strip cannot fit tightly due to relaxation, and air can enter the room through the gap. At the same time, the locking point and lock seat of the lock are less accurate, which may cause uneven force when the door leaf is closed, further damaging the integrity of the sealing system.
The long-term effect of environmental factors has a cumulative effect on the door structure. The high humidity environment will accelerate the rust of metal parts and the aging of rubber strips. Salt spray corrosion in coastal areas may also weaken the oxide film on the surface of aluminum alloy profiles, resulting in an increase in the thermal conductivity of the profile itself. Corrosive substances such as acid rain will corrode the sealing strips and insulation strips, causing their physical properties to deteriorate. In areas with large temperature differences, the door body frequently experiences hot and cold cycles, the thermal expansion and contraction of the material increases, and structural cracks are more likely to occur at the interfaces of the components. For example, the corner code connection parts at the splicing of the profiles may become loose after long-term stress, and the air in the gap becomes a heat conduction medium.
Human use habits and maintenance conditions will also affect the durability of thermal insulation performance. Frequent and forceful opening and closing of the door will aggravate the wear of hardware accessories and deformation of the rubber strips. Improper cleaning methods such as the use of strong acid and alkali cleaners may corrode the rubber strips and profile surface coatings. If the dust and accumulated water in the door frame groove are not cleaned in time during daily maintenance, the accumulation of debris will hinder the normal closure of the rubber strips, and long-term immersion in accumulated water may cause corrosion at the bottom of the profile. In addition, unauthorized modification of the door body structure, such as adding additional metal components to the door leaf, may destroy the original thermal insulation design and form a new heat conduction path.
Hidden defects in the installation process may gradually appear in long-term use. If the filling material between the aluminum alloy thermal insulation swing door door frame and the wall is improperly selected or the construction is not standardized, a thermal bridge effect will be formed. For example, if ordinary cement mortar is used for filling instead of thermal insulation materials such as polyurethane foam, the contact area between the wall and the door frame becomes a heat transfer channel. If the verticality and horizontality of the door frame are not adjusted properly during installation, the door body will be in a stress state for a long time, which may cause the profile to deform or the insulation strip to break. If the thickness and continuity of the sealant are insufficient, water seepage and air permeability points will form due to cracking of the glue layer in the later use. These hidden dangers in the installation stage are gradually exposed over time and become potential factors for the attenuation of thermal insulation performance.
