RU239146U1 - DOOR LEAF FOR INTERIOR DOORS - Google Patents

Abstract

The utility model relates to the construction and equipment of buildings and premises, in particular residential premises. The door leaf for an interior door is made in the form of a frame structure of at least two vertical bars 1, 2 and two horizontal bars 3, 4, connected to said at least two vertical bars, and an internal filling element 5, located inside said frame structure and representing a structure of at least three layers. The middle layer of said internal filling element is made of polystyrene concrete with a thickness of 20-70 mm and a density in the range of 80-350 kg/ ^m3 , wherein the polystyrene concrete consists of polystyrene beads 55-75%, cement 15-22%, water 12-18% and plasticizers 0.1-0.5% by weight of the cement. The technical result, which the utility model is aimed at, consists in increasing the fire resistance of a lightweight interior door, characterized by high manufacturing efficiency, due to a simple manufacturing technology, minimal cost, high thermal insulation and a long service life.

Description

The utility model relates to the construction and equipment of buildings and premises, in particular residential premises.

Modern construction technologies and the demands for comfortable living spaces make interior doors that combine lightweight construction, thermal insulation, ease of manufacture, and fire safety requirements highly relevant. The technological design of a fire-resistant door leaf is a critical factor determining its cost-effectiveness, quality, and competitiveness. These properties are important because the lightweight construction of an interior door reduces hardware wear and extends its service life, and installation requires less effort. High thermal insulation ensures energy efficiency and reduces heat loss between rooms, eliminating drafts and temperature fluctuations. Good sound insulation reduces sound levels to 30-42 dB. Fire resistance (fire resistance) improves safety and prevents irreparable losses.

A door leaf for an interior door is known (patent for utility model of the Russian Federation 205328, application 2020117874, publication date 07/08/2021, IPC E06B 3/72, E06B 5/20), made in the form of a frame structure of at least two vertical bars and two horizontal bars connected to the said at least two vertical bars and an internal filling element placed inside the said frame structure and representing a structure of at least three layers, wherein the middle layer is made of pressed wood fiber with the addition of a polymer binder.

The disadvantages of this analogue are:

swelling of wood fiber when exposed to water;

lower thermal conductivity (0.12-0.18 W/(m⋅°C));

door leaf weight from 25 to 40 kg (for a leaf of 80×200 cm);

a complex manufacturing technology associated with preliminary preparation of raw materials (wood chips), grinding and processing of fiber, mixing with a polymer binder;

low sound insulation from 25 to 37 dB;

When using a door leaf filled with lightweight concrete of a porous structure on a cement binder and a filler made of foamed granular polystyrene with the use of air-entraining additives that porous the cement stone, compared to an analogue, it allows for an improvement in thermal insulation by 30-40% (0.07–0.10 W/(m⋅°C)), eliminates deformation of the leaf when water gets in, reduces the load on the fittings due to the light weight of the door from 15 to 25 kg, and also increases sound insulation up to 42 dB.

A door leaf for an interior door is known (patent for utility model of the Russian Federation 46258, application 2004124437, publication date 06/27/2005, IPC E06B 3/00), containing a frame and a protective filler based on glass fiber concrete.

The main disadvantages of the prototype are:

high density (1800-2200 kg/m³), which leads to a significant weight of the door leaf (40-60 kg for a standard size of 800×2000 mm), increased load on the fittings and door frame, complicated installation and the need to strengthen the door structures;

limited thermal insulation (λ = 0.5-0.7 W/(m⋅°C)), which is insufficient for effective energy saving;

complexity of processing (requires specialized tools for cutting and milling;

high manufacturing costs due to expensive fiberglass reinforcement.

The technical problem solved by the proposed utility model is the creation of a technologically advanced lightweight door leaf for an interior door, allowing for an increased service life of the installed interior door with high thermal insulation properties, as well as low energy consumption, manufacturing costs, and increased fire resistance.

The technical result, which the utility model is aimed at, consists in increasing the fire resistance of a lightweight interior door, characterized by high manufacturing efficiency, due to a simple manufacturing technology, minimal cost, high thermal insulation and a long service life.

The simple manufacturing technology for lightweight fire-resistant door panels improves processability by simplifying the production cycle. This simplification is achieved by mixing components (cement, polystyrene granules, water, and plasticizer) without the need for complex equipment, enabling cold molding instead of energy-intensive hot pressing, and eliminating the need for vibration compaction and lengthy drying.

The minimal cost of manufacturing a lightweight fire-resistant door panel is influenced by the availability of the components used. Polystyrene granules are a common petrochemical product, and cement is a readily available building material. Low energy consumption is achieved by eliminating heat treatment.

The high thermal insulation of the lightweight fire-resistant door leaf influences its manufacturability due to the inclusion of polystyrene granules, which impart high thermal insulation properties to polystyrene concrete, eliminating the need for additional insulating layers.

The long service life of the lightweight fire-resistant door is influenced by its manufacturability due to the use of polystyrene concrete, which does not require special storage and transportation conditions, is moisture-resistant, prevents warping, maintains its geometry throughout its entire service life, and does not require additional treatment with protective compounds.

The technical result in the utility model is achieved due to the fact that the door leaf for an interior door is made in the form of a frame structure of at least two vertical bars and two horizontal bars connected to said at least two vertical bars and an internal filling element placed inside said frame structure and representing a structure of at least three layers, and the middle layer of said internal filling element is made of polystyrene concrete with a thickness of 20-70 mm and a density in the range of 80-350 kg/ ^m3 , wherein the polystyrene concrete consists of polystyrene balls 55-75%, cement 15-22%, water 12-18% and plasticizers 0.1-0.5% by weight of the cement.

To increase the fire resistance of the door leaf, it is possible to make an internal filling element with additives of perlite and lime.

To enhance structural reliability, the vertical and horizontal beams are made of solid softwood or hardwood. Solid wood provides frame rigidity, compensating for the low load-bearing capacity of polystyrene concrete. The coefficient of linear expansion of wood (0.01-0.03 mm/(m⋅°C)) matches that of polystyrene concrete (0.05-0.08 mm/(m⋅°C)), preventing deformation.

The outer layers of the specified internal filling element are made of wood-fiber boards with a thickness of 3 to 8 mm to ensure a balance between the strength and weight of the door leaf.

Polycarboxylate or sulfonate plasticizers are used as plasticizers for polystyrene concrete in a dosage of 0.2-1.5% of the cement mass, which ensures a reduction in the water requirement of the mixture (minimization of shrinkage and cracking), increased mobility without delamination of components, and improved adhesion of cement to polystyrene granules.

In addition, polystyrene concrete additionally contains microsilica in the amount of 2-5% of the cement weight to improve mechanical characteristics (compressive strength increases by 15-25% (up to 4.5-5.5 MPa at a density of 350 kg/m³), adhesion to a wooden frame increases by 30-40% (up to 1.2-1.5 MPa), impact strength increases by 1.5-2 times (up to 1.8-2.2 kJ/m²)) and optimize the structure of the material (filling micropores (particle size 0.1-0.5 μm), reducing capillary porosity by 20-30%, stabilizing polystyrene granules, uniform distribution of the filler).

Between the polystyrene concrete core and the outer layers, 0.5-1.5 mm thick polyurethane adhesive layers are placed to improve mechanical properties (impact strength increases by 1.8-2.2 times, resistance to delamination under cyclic loads increases) and optimize acoustic properties (sound insulation improves by 3-5 dB, vibration damping increases by 25-30%). The 0.5-1.5 mm polyurethane adhesive ensures rapid setting (10-15 minutes at 20°C). Alternative adhesives may be used in production.

In order to improve fire safety while maintaining the lightness of the door leaf, the polystyrene balls are made of self-extinguishing polystyrene grade PSV-S.

Port-lattice cement is used as a cement for polystyrene concrete, ensuring the performance characteristics of door panels while reducing material consumption and production costs. The use of port-lattice cement reduces the drying time of the mixture and increases its strength.

The utility model is illustrated by drawings:

Fig. 1 - shows a general view of the door leaf.

Fig. 2 - shows a cross-section A-A of the door leaf according to Fig. 1.

The door leaf for an interior door is constructed as a frame structure and comprises two vertical bars 1 and 2 (or more, not shown) made of solid wood and connected by two horizontal bars 3 and 4, also made of solid wood, and an internal filling element 5 located within said frame structure. Internal filling element 5 is a structure of at least three layers: outer layers 6 and 7 and a middle layer 8.

As shown in Fig. 2, the middle layer 8 of said inner filling element 5 is made of polystyrene concrete with a thickness of 20-70 mm and a density in the range of 80-350 kg/ ^m3 , for example, from a fire-resistant, heat-insulating board. The outer layers of said inner filling element 5 can be made of wood-fiber boards (HFB) with a thickness of 3 to 8 mm and can extend onto the surfaces of the bars 1, 2, 3, 4 of the frame structure.

The vertical bars 1 and 2 and the horizontal bars 3 and 4 of the frame structure are connected using fasteners or a tongue and groove system.

The stated door leaf for an interior door measuring 2000×800 mm is manufactured as follows.

Prepare the wood components. Select solid softwood or hardwood blocks with a moisture content of 8±2%. Vertical blocks are cut to match the door leaf height, allowing for a 10 mm allowance. Horizontal blocks are cut to match the door leaf width, minus the thickness of the vertical blocks on both sides.

They prepare polystyrene concrete components.

Components of polystyrene concrete:

Portland cement M500 D0: 15-22% of the mixture volume

Polystyrene beads PSV-S (fraction 2-5 mm): 55-75%

Microsilica (specific surface area ≥20,000 m²/kg): 2-5% of cement mass

Polycarboxylate plasticizer: 0.2-1.5% of cement weight

Water: 12-18% of total volume.

If necessary, perlite and lime are added to increase fire resistance.

The door frame is assembled. The vertical and horizontal beams are joined using a tongue and groove system. The corners are reinforced with metal plates. The door frame geometry is checked.

Preparing the polystyrene concrete mix. Portland cement and microsilica are added to a forced-action concrete mixer and dry-mixed for 1 minute. A plasticizer dissolved in water is added and mixed for 2 minutes. Polystyrene beads are added and mixed for 3-4 minutes.

Forming the middle layer of element 8 of the inner door panel infill. The frame is installed in a Teflon-coated mold. Polystyrene concrete is poured with vibration compaction (frequency 50 Hz, amplitude 0.5 mm). The concrete is maintained under a pressure of 0.05-0.1 MPa for 40-60 minutes. Alternatively, the polystyrene concrete is poured into the mold, after which sheets of the required thickness are cut, which are then used to assemble the door panel.

The door panel is assembled using a three-layer structure. If necessary, polyurethane adhesive with a viscosity of 3000-5000 mPa⋅s is applied to the bottom and top layers of MDF (3-8 mm) at a thickness of 0.5-1.5 mm. A middle layer of polystyrene concrete is placed between the bottom and top layers of MDF. The panels are pressed at 0.2-0.3 MPa (20-30°C) for 2-3 hours.

Mechanical processing is performed after 24 hours (edge milling and drilling holes for hardware). A protective and decorative coating is applied, followed by priming, painting, or lamination.

They carry out quality control of the finished product.

Compressive strength: ≥2.5 MPa (GOST 10180)

Thermal conductivity: ≤0.12 W/(m °C) (GOST 7076)

Fire resistance: flammability group G1 (GOST 30244)

Sound insulation: up to 42 dB (GOST 26602).

The door leaf, measuring 800 x 2000 mm and featuring a 50 mm thick core, weighed 25 kg, with a polystyrene concrete density of 150 kg/m³. Manufacturing time for the door leaf was three working days. The ease of assembly thanks to the frame construction and the ability to automate polystyrene concrete pouring, which is less labor intensive than with solid wood doors or doors with a glass fiber reinforced concrete core, demonstrate the manufacturability of the lightweight and fire-resistant door leaf.

The proposed design of the interior door leaf allows achieving the stated technical result, which consists of high fire resistance of a lightweight door leaf structure, which is highly technological due to a simple manufacturing technology, minimal cost, high thermal insulation and a long service life, while having high fire safety (fire resistance) due to the use of non-combustible polystyrene concrete.

Tests of a door structure with polystyrene concrete were conducted. Results were obtained according to the EI-30 test protocol. The door leaf thickness was 45 mm. The design of the declared door leaf allows for fire-rated doors to be produced with EIS-15 and EIS-30 ratings. With additional stone wool interlayers, the door leaf design allows for fire-rated doors to be produced with EIS-60 and EIS-90 ratings.

Claims (8)

1. A door leaf for an interior door, made in the form of a frame structure of at least two vertical bars and two horizontal bars connected to said at least two vertical bars, and an internal filling element placed inside said frame structure and representing a structure of at least three layers, characterized in that the middle layer of said internal filling element is made of polystyrene concrete with a thickness of 20-70 mm and a density in the range of 80-350 kg/ ^m3 , wherein the polystyrene concrete consists of 55-75% polystyrene balls, 15-22% cement, 12-18% water and 0.1-0.5% plasticizers by weight of the cement. 2. A door leaf according to paragraph 1, characterized in that said vertical and horizontal bars are made from solid coniferous or deciduous wood. 3. A door leaf according to paragraph 1, characterized in that the outer layers of the said internal filling element are made of wood-fiber boards with a thickness of 3 to 8 mm. 4. A door leaf according to paragraph 1, characterized in that polycarboxylate or sulfonate plasticizers are used as polystyrene concrete plasticizers in a dosage of 0.2-1.5% of the cement weight. 5. A door leaf according to paragraph 1, characterized in that the polystyrene concrete additionally contains microsilica in an amount of 2-5% of the mass of the cement. 6. A door leaf according to paragraph 1, characterized in that between the middle polystyrene concrete layer and the outer layers there are adhesive layers based on polyurethane adhesive with a thickness of 0.5-1.5 mm. 7. A door leaf according to paragraph 1, characterized in that the polystyrene balls are made of self-extinguishing polystyrene grade PSV-S. 8. A door leaf according to paragraph 1, characterized in that portlattice is used as cement for polystyrene concrete.