Title of Invention: Insulated clay bricks using layers of air and flexible polyurethane foam.

[0001] This statement has been prepared on February 02, 2021 based on No.139950140003008846 local statement filed with the Iranian Intellectual Property Organization (IRIPO).

Technical Field

[0002] This invention can be used in sciences such as civil engineering, architecture, mechanics, industrial design, construction management, chemical engineering, earthquake engineering, materials metallurgy and industrial construction.

Background Art

[0003] Bricks (in ancient times) are called adobes, on which government decrees and command are written (engraved). By baking these adobes (brick is a kind of adobe, but the adobe is made using mud and straw), the writing on it became stable and lasting. It is not clear when and where the brick was first used. Early humans are thought to have noticed the properties and methods of making bricks by observing the clay being baked next to their stoves and seeing that the cooked clay was harder than other clods, and thus discovered bricks (adobes). Brick has also been used as a building material for a long time. The use of bricks as building materials in Iran has an ancient history. One of the famous ancient buildings that is made of brick is Taq Kasra. Another example is the floor of the corridor of the Jameh Mosque of Isfahan, which is furnished with bricks that were used to build a fire temple during the Sasanian Empire. In general, the use of bricks has been very widespread throughout the history of Iran, and countless buildings, including fire temples, mosques, residential buildings, etc., have been made of bricks in Iran. At present, due to the increase in population density and the construction of multi-storey buildings; it is not possible to use bricks in the skeleton of this type of building; so steel or concrete skeletons are used. However, the bricks are used for decoration or in a part of the hall and other spaces; also the bricks are often used in a visible way. Bricks can be classified in different ways. These classifications include colors, dimensions, and materials. Brick is divided into two categories based on the type of material: [0004] Pressed brick: The reason for naming this type of brick is that at the beginning of the production of this type of brick, its adobes were made by hand and the corners of the mold were filled with special clay by the hands pressure of the bricks workers. The dimensions of this type of brick are 22*11 *5.5 or20*10*5 cm. This type of brick is suitable for all construction works such as Arrange the bricks in the shape of knots, barrel-vault, load-bearing walls, and the construction of thin walls.

[0005] Machine bricks: Machine bricks or perforated bricks, on its larger surface there are 8 or 10 holes with a diameter of 1 .5 -2 cm and in the Iranian market, they are known as eight or ten machine holes’ bricks. In Standard No. 7 of the Institute of Standards and Industrial Research of Iran, these holes must pass through the entire thickness of the brick and the total cross section of the holes should not be more than 25% of the larger brick surface. And the distance of the holes from the edge of the brick and also the distance of the holes from each other, in each dimension of the brick, should not be less than 30% of the length of the same dimension. The reason for these holes is that during masonry, mortar and cement penetrate vertically into the brick and make the wall stronger. This type of brick is used in the construction of load-bearing walls because it can be reinforced with rebar through holes in the surface of the brick. Reinforced brick wall is built to withstand the force of an earthquake. The material of this type of brick is very brittle compared to Pressed bricks and its suction property is less than Pressed brick. These bricks cannot be sharpened due to their brittleness and also because they do not have much suction property and cannot adhere well to the mortar, so they are not used in barrel-vault. The dimensions of this type of brick are 22 * 11 * 5.5 cm. The sides of this type of brick are right-angled and have smoother surfaces than pressed bricks.

[0006] Pottery brick is one of the most widely used building materials used for masonry. The reason for this can be explained as follows: "In today's modern structures, the walls no longer have a load-bearing role, because the loads are often transferred to the foundation and the ground through the building skeleton. In fact, the walls do not need extra strength and are used only for privacy and separation of spaces. Pottery bricks are made using clay, in which clay is mixed with water and then molded. After the clay molds have dried in the outdoor, they are placed in a kiln at a temperature of 40 to 200 degrees Celsius, then after two days, the bricks are removed from the kiln. In general, this type of brick is produced in two ways, both traditional (handmade and molded) and modern (industrial). The end product is a cube-shaped material with regular horizontal holes. The number of holes in this brick varies depending on its dimensions.

Summary of Invention

[0007] Insulation clay bricks using layers of air and flexible polyurethane foam is a type of clay bricks using layers of air insulation and polyurethane foam. In industry, one of the most important points is to reduce energy waste. This point is so fundamental that in the beginning of the development of the industry, in order to reduce the damage to employees, the use of various types of insulation in industrial systems was expanded. After the expansion of the use of insulation in industry, the issue of reducing heat loss in most industries, including the construction industry, was raised. In buildings, efforts are made to increase the strength of the structure and reduce the overall weight of the building. It is also important to reduce the power of sound transmission and heat transfer in the walls. Among the insulators, the most important points are reasonable price and high efficiency, which are calculated and examined according to the lifespan of these insulators. In this regard, the best type of insulation, with these properties of flexible polyurethane foam, is produced from a combination of polyols and diisocyanates. Another type of insulation with very high efficiency is air. In the claimed invention, by combining these two insulations, the production of bricks has a very high insulation efficiency, features such as sound insulation, weight loss and increase the building's resistance to earthquakes.

Technical Problem

[0008] Problems with ordinary clay bricks: Clay is relatively better heat transfer than other materials used in buildings, so in tall buildings where the weight of the structure is very important, more clay bricks are used and therefore Heat transfer increases due to the movement of air inside this type of brick. Other disadvantages include low strength and high sound transmission.

[0009] Problems in Pressed bricks: Although this type of brick has better resistance than clay bricks and shows a lower number than heat in terms of heat transfer coefficient, however, due to the uniform shape of this brick, even It transfers more heat than the previous system.

[0010] Problems in cement blocks: Disadvantages of these building materials include high weight, high heat transfer and difficulty of transportation.

[0011] Problems with machine bricks: This type of brick is similar to clay bricks, but has a much denser texture and has a very high heat transfer.

[0012] Problems in refractory bricks: It is worth mentioning that this brick has the highest heat transfer rate among all bricks.

[0013] Problems with thermal insulation clay bricks: This type of brick, as its name implies, has relatively better insulation, but it still does not provide resistance to sound and the air circulation inside it is still high.

[0014] Problems in glazed bricks: the cost of making this type of brick is relatively high, the possibility of heat transfer from it, even compared to clay bricks, is a little more, and it is only used in the facade of the building, which is very similar to refractory bricks.

Solution to Problem

[0015] The main objectives are to reduce heat and sound transmission and reduce production costs by using layers of polyurethane foam and air in clay bricks.

[0016] The materials required for the production of bricks are as follows:

[0017] the 60-65 % clay, dune sand 15-10 %, soil 25-10% and carbon 10-5% are used. (Here the percentage means weight percentage).

[0018] The materials required to produce foam are as follows:

[0019] Diisocyanate, polyol with a composition of 55%, ethylene glycol 35%, glycerin and other materials are polyols with higher grades. Of course, these materials are readily available in the market. The diisocyanates and polyol solution with equal mass percentage are mixed.

[0020] To produce hollow pottery bricks, the raw material consisting of; 60-65 % clay, dune sand 15-10 %, soil 25-10% and carbon 10-5%. are used (Here the percentage means weight percentage, the dry matter and water is added to 8 - 12% of the total weight to the mixer then grinds the particles into the machine to make it finer. Mix the output material of the rollers with 8 to 17% of excess water and pour it back into the mixer, then mold it into a final shape with a grinder (similar to a meat grinder).

[0021] A cutting machine then cuts each piece of brick. After production and formation, the raw clay bricks are placed in a dryer at a temperature of 40 to 200 ° C for 24 to 48 hours. To bake clay bricks, a tunnel kiln with a center temperature of 900 to 1 100 degrees Celsius is used. Baking time varies from 40 to 80 hours. To mold the foam, first two pieces of brick are placed in parallel in the mold, and then the raw materials of the foam are injected into it at a speed of 1 g / s. (For 10 to 15 seconds). For firmness and proper production, flexible brick polyurethane foam is placed at 40 to 55 ⁰ C for 15 minutes. To create the lowest amount of heat transfer, diisocyanates and polyols with a composition of 55% ethylene glycol and 35% glycerol are used, respectively, and finally polyols with higher grades are used.

Advantageous Effects of Invention

[0022] Low construction cost

[0023] No need for training to implement

[0024] Possibility of industrialization

[0025] Availability of devices required for industrialization

[0026] Possibility of using the production line

[0027] Low cost of materials

[0028] Availability of consumables

[0029] Reduction of heat transfer by more than 92.5% compared to machine bricks and more than 95% compared to refractory bricks

[0030] Reduce the intensity of sound transmission by more than 60%

[0031] Ease of changing the size and shape of the exterior

[0032] Lack of insulation deterioration for a long time

[0033] Insulation properties do not decrease over time

[0034] Prevent air circulation inside the brick [0035] Good mechanical strength

[0036] Significant reduction in the production rate of toxic fumes during fires

[0037] High earthquake resistance

Brief Description of Drawings

Fig.1

[0038] [Fig.1 ] Front view

Fig.2

[0039] [Fig.2] View from above

Fig.3

[0040] [Fig.3] View from the left

Fig.4

[0041] [Fig.4] Isometric view

Fig.5

[0042] [Fig.5] methods of producing this brick

Diag.1

[0043] [Diag.1] Comparison of heat transfer rates

Diag.2

[0044] [Diag.2] Comparison of thermal conductivity

Diag.3

[0045] [Diag.3] R rate comparison

Tab.1

[0046] [Tab.1 ] Thermal profile table

Fig.6

[0047] [Fig.6] performed Calculations

Description of Embodiments

[0048] According to Tab.1 , this brick is made based on air insulation, polyurethane foam and temperature drop properties for all seasons, which according to the design mode, also shows the ability of sound insulation. Due to the ability of the components to reduce heat transfer, it is designed to provide the best efficiency.

[0049] According to the Fig 1 to 4, each brick is composed of three parts, namely: (1 ) polyurethane foam (2) pottery and (3) parts including air. In this type of brick, the central thermal insulation is composed of polyurethane foam and pottery on both sides of the brick, which ensures the strength of the brick. In addition, the empty part of this brick, in addition to the advantage of using air insulation properties, significantly reduces the production cost. In the construction of this brick, the design and location of the components is very important, so that with the formation of air that gets trapped inside it, it is done only in the form of conduction and no heat transfer (convection) occurs. This reduces the heat transfer coefficient, which in turn provides this feedback. Due to the ability to repel the vibration of flexible foam, this system also shows more resistance against earthquakes. It also contributes to the strength of the whole structure. Each row of bricks in this design acts as a unified pendulum, preventing severe vibration of the doorframe. Another point in this regard is the biodegradability of polyurethane, which makes this brick an environmentally friendly brick. In the design and construction of this brick, the issue of reducing production costs and increasing production efficiency has been carefully considered; as a result, the production cost is almost similar to insulation bricks available in the market.

Examples

[0050] According to Fig.5, to produce thermal and acoustic insulation bricks, based on foam and air, a process based on the properties of air insulation and polyurethane foam is required, which consists of the following steps.

[0051] A. Making hollow clay bricks and the baking process:

[0052] 1 . Production of brick section

[0053] 2. Material composition

[0054] 3. Crush

[0055] 4. Shaping

[0056] 5. Drying

[0057] 6. Baking bricks [0058] B. Molding polyurethane inside the brick

[0059] 7. Polyurethane molding

[0060] 8. Mixing foam

[0061] 9. Inject foam into the brick

[0062] 10. Heating

Industrial Applicability

[0063] The method of using this brick is exactly like ordinary clay bricks, with the difference that it is not used for load-bearing walls and can be applied to nonload-bearing walls. For the full efficiency of all insulation, it is strongly recommended that a small diameter cement layer be applied to the outer wall. In order to perform correctly and optimally, it is necessary to observe the mentioned points.

[0064] This brick is also prohibited in buildings exposed to constant fire (walls of furnaces, stoves and ovens). This ban is due to the production of cyanide gas from polyurethane when exposed to heat.

Reference Signs List

[0065] 1 . Polyurethane foam

[0066] 2. Pottery

[0067] 3. Part includes the air