Coating knowledge: Discussion on the application of various forms of polyurethane exterior wall insulation

Core tips: a brief discussion on various forms of polyurethane external wall insulation applications: (1), on-site pouring polyurethane, the current building method is to form polyurethane rigid foam in the cavity formed between two walls After polyurethane foaming, it forms a whole with the inner and outer walls Polyurethane foam penetrates into the brick joints of the wall, and the new wall has a strong overall effect It is required that the strength of the foam itself is higher than that of the ordinary foam The wall should be fully dried to avoid the lack of adhesion The other is to pay attention to the pressure generated during foaming to prevent wall deformation In practice, the solution is not to pour too much each time, so as to reduce the pressure generated by each foaming Which is the price of Dajin diatom mud Recommended brief introduction: which is the price of Dajin diatom mud? How to buy genuine diatom mud? Guangdong diatom mud agent suggests placing a basin of cold water in the air conditioning room, so that the diatom mud wall can breathe effectively The feature of the breathing wall is obvious When the indoor air is dry, the diatom mud wall will release the absorbed water quickly Put it out to help regulate the indoor dry humidity It is suggested to place a basin of cold water in the air conditioning room, so that the wall of diatom mud can breathe effectively The feature of the wall that can breathe is obvious When the indoor air is relatively dry, the wall of diatom mud will absorb the water Paint Home News: on various forms of polyurethane external wall insulation applications: (1), on-site pouring polyurethane, the current building method is planted in the cavity between the two walls to form polyurethane rigid foam After polyurethane foaming, it forms a whole with the inner and outer walls Polyurethane foam penetrates into the brick joints of the wall, and the new wall has a strong overall effect It is required that the strength of the foam itself is higher than that of the ordinary foam The wall should be fully dried to avoid the lack of adhesion The other is to pay attention to the pressure generated during foaming to prevent wall deformation In practice, the solution is not to pour too much each time, so as to reduce the pressure generated by each foaming After the wall solidifies to the highest structural strength, foaming can be carried out Another way of on-site pouring polyurethane for external wall insulation is to pour it on the external wall of the building The specific method is: firstly, the structural support is embedded on the wall, then the formwork is fixed on the support, polyurethane is poured in the cavity between the wall and the formwork which has been reserved by the support, and the next plate is poured in this order, these structural supports can be the support points for the next step of external protection and external decoration (2) after the on-site pouring polyurethane insulation is dried on the building wall, the polyurethane can be directly sprayed on its surface Generally, the spraying thickness is about 4cm It is required to use high-pressure spraying machine (www.cnbaowen Net) to make the surface as flat as possible After spraying the polymer cement on the foam after spraying, and then carrying out the exterior decoration, or adding the color paste and quartz sand into the polymer cement, the strength of the protective layer can be increased, and the surface will be beautiful The Canadian company is unique in their practice They first put wooden strips on the outside walls, spray them between each piece of wood, cut the foam out of the wood parts, and finally nail the decorative and protective sheets onto the wooden strips The method is characterized by overall flatness and convenient decoration treatment, which is suitable for the insulation of the highly irregular buildings (3) The prefabricated thermal insulation sandwich board generally adopts the polyurethane sandwich board processed on the continuous production line The outer surface is usually made of color steel plate or aluminum plate, and the back is made of aluminum foil During installation, the keel is made on the outer wall first, and then the plate is fixed on the keel Some of them also use double-sided color steel plate as the wall material As a representative product of polyurethane sandwich panel for external wall insulation, it is the product of German noble company, whose weight per square meter is only about 3.7 company It is beautiful and has good heat preservation effect (4) Filling and heat preservation of hollow brick the cavity part of hollow brick accounts for about 40% of the total volume of the brick Most of the bricks are made of silicate materials Polyurethane is poured into the cavity to enhance the overall structure and greatly increase the heat insulation effect Now large energy-saving buildings have adopted this material (5) the external wall paster is generally applied with special polyurethane adhesive on the dry external wall The adhesive has high initial adhesion and good hydrolysis resistance stability The pre cut polyurethane board (with clean surface and no sawdust) is pasted on the outer wall, the adhesive is applied on the outer surface of the polyurethane, the grid cloth is pasted, the polymer cement is applied after it is solidified, and the outer surface is decorated at last This practice is rare in China, but this technology is very popular The insulation board is made of extruded polystyrene foam (XPS) 2 At present, polyurethane is more and more used in the roof insulation of buildings in our country, the most common is spray foam and board, and sandwich board is also used The following is a brief introduction: (1) spray foam is commonly used in the roof cement mortar layer directly spraying polyurethane foam, mostly in 4-5CM thick, 30-40kg/m3 density, after completion, generally put metal mesh, cement mortar leveling, and then waterproof layer But some are made waterproof layer, and then spray In this way, the sloping roof is the most common, and the rigid polyurethane foam after spraying forms a tight whole without joint, so the heat preservation effect is very good If the subsequent construction is protected, polyurethane foam can play a certain role in auxiliary waterproofing (2) Lay polyurethane board, stick the cut polyurethane board on the roof with adhesive, and apply certain pressure to make the next board laying after curing Generally, a gap of no more than 2cm is reserved between plates Finally, the mixed polyurethane is poured into the gap with a pouring bag, which is pressed by a plastic film and a wooden box, so that the polyurethane becomes a whole The heat preservation of this method is often seen in the plane, which is characterized by evenness and uniformity, and is convenient for subsequent construction However, the board is easy to absorb moisture because it is not protected by skinning This method generally adopts the polyurethane sandwich board of double-sided color steel plate, whose surface layer can press patterns similar to tile shape This makes the roof look more beautiful after construction This kind of tile shaped sandwich board is fixed on the keel of the roof It is fixed on the roof by means of bolts and broaching nails Sealant is added at the joint to prevent the leakage of the roof and the corrosion of the color board caused by the water stop In addition to the above three common practices, Canada's Anne's method is to use the bottom of the pointed roof to spray wood keel foam and redecorate it This method is more suitable for the preservation of the special-shaped roof such as villa buildings 3 The caulking and sealing of buildings, doors and windows and through holes, etc., all have gaps in buildings, which are the factors of building energy consumption In the past, the method is to fill the broken cement or brick and then plaster the cement Because the filling is not solid, the internal cavity becomes the hidden danger of building energy saving The polyurethane single component rigid foam is loaded into the pressure container barrel When using, the valve is pressed to make the foam flow out, because the foam just out of the pail is soft and can be deformed arbitrarily In this way, it is possible to squeeze the foam into the gap around the window through the thin tube, solidify the foam and harden it slightly Through holes in buildings, such as air conditioning holes and cable holes, can be filled with it 4 There are two kinds of thermal insulation building pipes: one is the air supply pipe of central air conditioning, the other is the heating pipe of building Most of the traditional air conditioning air supply pipes are rectangular pipes made of sheet iron or fiberglass There are many pipes with poor or even non thermal insulation, which makes the energy loss of many cold (hot) air in the transportation process serious In recent years, polyurethane sandwich panel with soft surface has brought a good solution to this problem The board is a sandwich board formed by double-sided aluminum foil and polyurethane It is very convenient to process pipes It can be finished by slotting with a 45 degree angle cutter It only takes less than 30 minutes for one person to complete a tee pipe with a sectional area of 0.5 square meters There are many advantages of this kind of air duct Here we just talk about its energy conservation, which is mainly due to its good heat preservation and tight sealing (minimal air leakage), which is incomparable to traditional materials Of course, the Fire Department of our country has high requirements on the flame retardancy of materials and incomplete standards, which makes this material still limited in China Another kind of thermal pipeline for buildings is mainly used for heating in winter in northern China The pipes in the building are mostly made of polyurethane rigid foam tiles The prefabricated insulation tiles are buckled onto the insulated pipes, the joints are painted with adhesive, or fixed with iron wire, and the glass fiber reinforced plastic protective layer is added outside In order to be beautiful, the outer protective pipes with aluminum foil are often added, which plays the role of radiant heat in addition to beauty In addition to the above products and applications, there are many other aspects in the application of polyurethane in building energy saving, such as many household appliances, such as refrigerators, ovens, water heaters, the insulation layer is mostly polyurethane insulation, in addition, solar water heaters can not be separated from polyurethane insulation to store hot water Polyurethane is one of the building sealants Thus, polyurethane has great potential in the field of building energy saving Polyurethane rigid foam is the most commonly used polyurethane material in the field of building energy saving It is mainly used for the painting of building exterior wall and the filling of polyurethane composite board in building wall Polyurethane rigid foam spraying is a new building energy-saving technology, which has good thermal insulation, stability, fire resistance, moisture and heat resistance, impact resistance, crack resistance, environmental protection and other characteristics Due to the fast construction speed and high efficiency of the external thermal insulation project of rigid polyurethane spraying, it has a strong adaptability to the shape of the building It can adapt to the thermal insulation of the complex parts of the structure node of the building, and the maintenance of the decorative surface of the external thermal insulation system of rigid polyurethane spraying is very convenient After maintenance, it can keep its appearance and function in good condition Polyurethane composite board is a kind of color steel sandwich composite board, which is composed of two color steel profiled boards and rigid polyurethane with automatic foaming in the middle It can be widely used in the exterior walls and roofs of various buildings, and is recognized as the best thermal insulation material in the world It can be used for roof and wall of large industrial workshop, warehouse, exhibition hall, gymnasium, cold storage, purification workshop and other buildings, integrating heat preservation, heat insulation, load-bearing and water-proof In addition, the thickness of the wall using polyurethane board is far less than the traditional building wall, and its insulation performance is multiple of the latter, so polyurethane composite board has also been widely used Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,