GR1010194B - Weightlight chimney's elements with incorporated heat insulation and steel flue - Google Patents

Abstract

Novelty: prefabricated in-height installed chimney elements. Technical features: the invented chimney elements consist externally of lightweight pumice-containing concrete and have, internally, a coaxial metal conduit of steel plate. Fireproof thermal insulation material is contained between the concrete lightweight concrete and the steel plate. Said elements are built one after the other in height for forming the chimney. A metal coaxial conduit extends upwards and has a male-type extension enabling its application to the in-height alternating chimney elements. Advantages: Stiffness in construction. Easy alignment during the in-height installation of the elements. Low construction weight. Reduced external chimney temperature and increased protection when the invented elements are in contact with wooden elements (roofs, frames). Fire protection because the pumice-containing concrete is fire resistant - class A1. Possibility to apply external coating for increased safety, repairability and aesthetic effect. High temperature of the exhaust gases immediately after leaving the hearth, facilitating the chimney’s draught and heat recovery in energy systems. Reduced accumulation of non-combustible material on the metal inner surface.

Description

Lightweight chimney elements with integrated thermal insulation and steel flue

The invention refers to prefabricated chimney elements, which are externally composed of lightweight concrete containing kisiri (kisirodem) and internally carry a coaxial metal duct made of steel plate. Fire-resistant heat-insulating material is contained between the veneer and the sheet.

In this description, claims and abstract it will be called:

Concrete mortar: A mixture of hydraulic cement mortar, water, concrete (light stone) and inorganic aggregates (eg sand, perlite), which has a dry apparent density of less than 2000 kg/m<3>. The tape hardens over time, gaining mechanical strength.

Chimney element: Pre-fabricated element, used to build a stackable chimney.

Current applications in the construction of chimneys in living spaces (houses, hospitality units) for fireplaces and biomass energy heating systems include:

. Construction of chimney elements of square or circular cross-section with material concrete of normal density or lightweight concrete which are built on top of each other with fire-resistant bonding mortar. The disadvantages of this construction are the significant weight of the chimney in the case of concrete of normal density (about 2350 kg/m<3>) and the gradual appearance of cracks at high temperature of the furnaces due to continuous contractions and expansions and disorganization of the hydrated phases of the concrete. This construction is not suitable for energy heating systems because the temperature of the exhaust gases is high and because the rough inner surface accumulates deposits of non-combustible material. Accumulation of unburnt material with insufficient maintenance creates an increased risk of deposit ignition and fire hazard. . Construction of chimney elements, which consist of two coaxial cylindrical metal plates, in the gap of which there is a refractory heat-insulating material. One end of each element is flared to fit into the overlying element. The advantage of this construction is the low total weight, and the reduced accumulation of deposits of non-combustible material. Main disadvantages are the difficulty of aligning the elements at the joint locations and the risk of high temperatures locally on the outer surface. High temperatures occur locally at the locations of the metal spacers that stabilize the distance between the coaxial conductors or from local movement or voiding in the thermal insulation material. Hot spots can also be created on external metal support plates and chimney support plugs External hot spots can cause a fire when in contact with combustible construction materials (eg wood).

The lightweight chimney elements of the present invention with integrated thermal insulation are designed to combine the advantages and address the disadvantages of current applications.

Figure 1 shows the representative form of a lightweight chimney element with integrated thermal insulation. It consists of a cross-section element (1) with an externally square (2) and internally circular (3) cross-section. Longitudinal holes (4) are formed in the four corners for the placement of reinforcement. The gift item provides the following benefits:

. Rigidity in construction.

. Ease of alignment when stacking vertically.

. Low construction weight (bundle density 1100 kg/m<3>)

. Additional protection from external hot spots because concrete is thermally insulating compared to normal density concrete. Increased protection is thus provided in contact with wooden elements (roofs, frames).

. Fire protection because the corduroy is fire resistance class A1. · Ability to apply an external coating providing increased safety, repairability and aesthetic effect.

A layer of flexible ceramic thermal insulation material (e.g. ceramic wool blanket) (5) is placed inside the circular section, which is resistant to high temperatures (1700 The ceramic thermal insulation material has a low thermal conductivity coefficient and its function is to thermally protect the corrugated iron from high flue gas temperature The heat-insulating material keeps the temperature of the flue gas high immediately after exiting the stove, facilitating chimney draft and heat recovery in energy systems.

Inside the heat-insulating material is the exhaust duct (6) consisting of a steel plate (sheet) 0.4-0.5 mm thick. It protects the thermal insulation material from exhaust gases and water vapor condensation and has the advantage of reduced accumulation of non-combustible material and, due to a smooth surface, better traction.

Figure 2 shows the side section of the chimney element. The extension of the metal duct (7), about 60 mm, can be seen, which enters the top of the superimposed chimney element. It can also be seen that the thermal insulation material protrudes (8) by approximately 5 mm to ensure continuity with the thermal insulation material of the chimney element below. The heat insulating material is fixed with ceramic glue on the outer surface of the metal duct.

Figure 3 shows details of the metal conduit. The extension (male) (7), the slotted area (female) where the extension enters when stacking, the perimeter stiffening ribs (10) and the grooves (11) for the placement of a fire cord also to increase stiffness can be seen. The design facilitates the placement of the elements and the alignment of the chimney.

Figure 4 shows the intersection of two superimposed elements. Mark the area (12) where the bonding mortar is applied with a thickness of approximately 5 mm. Figure 5 shows an enlargement of the area (12) where the binding mortar (13) can be seen.

Bibliography

1. ELOT EN 13229 "Inset devices, solid fuels - Requirements and methods including open burners test"

Claims (5)

1. Prefabricated chimney elements which consist externally of lightweight concrete containing kisiri (kisirodema) and carry internally a coaxial metal duct made of steel plate. Fire-resistant heat-insulating material is contained between the veneer and the sheet. 2. Prefabricated chimney elements as in claim 1, which are built one on top of the other in height to construct the chimney. 3. Prefabricated chimney elements as in claim 1, in which the refractory heat insulating material is ceramic wool blanket. 4. Prefabricated chimney elements as in claim 1, in which the metallic coaxial duct extends towards one base and is widened towards the other base for its application to the superimposed element. 5. Prefabricated chimney elements as in claim 1, in which the heat-insulating material is fixed with ceramic glue to the outer surface of the metal duct.