JPS5818586B2 - Fire retardant low temperature insulation panel and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in insulated doors, building panels and the like, and more particularly to improved insulated panels for cold storage rooms.

Foam plastic resins have extremely low thermal conductivity at low temperatures, making them excellent materials for insulating refrigeration wall panels.

The best and most commonly used of these plastic insulation materials for the above-mentioned purposes is polyurethane foam.

However, these materials have the serious drawback of disintegrating when exposed to high temperatures.

Some, like polyurethane foam, are flammable and produce toxic fumes when ignited.

When fire safety is an important factor, polyurethane foam insulated panels require supplemental fire resistant panels to provide fire protection and meet code and insurance requirements.

The present invention addresses the pressing need for the combined nature of a fire-resistant door and an efficient refrigeration door, providing a dual quality in a single panel hitherto not available in a single refrigeration door or panel. It is something that fulfills your needs.

metal clad refrigeration doors, including polyurethane foam insulation;
The panel or equivalent has a solid layer of non-combustible thermally expandable composition material between the covering metal and the urethane foam core.

According to the invention, the material sandwiched between the core material and the casing wall consists essentially of hydrous sodium silicate, preferably held with a bond of glass or asbestos fibers.

At temperatures in excess of 200°F (approximately 93.3°C), the initially solid or crystalline sodium silicate expands and transforms into a rigid, porous, relatively thick coating or layer with high temperature resistant insulation properties. , converting the panels into effective fire- and heat-resistant barriers.

A primary object of the present invention is to provide an insulated door or other architectural structure that exhibits excellent resistance to heat transfer under relatively low ambient conditions and that provides an effective fire-resistant, heat-resistant barrier when subjected to high temperature heat. It is provided by the panel.

Yet another object of the present invention is to provide a door or panel having the above-described thermal and fire-resistant properties and meeting code and insurance carrier requirements for refrigeration and fire-rated doors.

These and other objects and advantages will become more apparent from the description below.

Referring to the drawings, the insulation panels are 5 and 6 respectively.
The outer wall axis and the inner wall side walls and top and bottom groove molds indicated by the IJ tubes 7 and 8 include a metal plate jacket or casing or box-like structure that views the IJ tubes 7 and 8.

These are thus preferably formed from sheet and strip metal materials.

In the case of certain commonly used types of cold storage door structure casings, these inner and outer panel members 5 and 6 have inwardly bent edge flanges 1.
0, these flanges 10 are interconnected by a closure strip 11 which is fixed to the flanges 10, such as by screws or rivets 16.

Vent holes 13 are provided in the earth wall for the release of gases and vapors generated within the casing by decomposition of the core as a result of high temperatures.

The opening 13 is sealed to prevent moisture from entering the casing through the ventilation opening 13 during normal use.

This is because the polyethylene film strip 14 is fixed on the inside of the casing wall under the ventilation openings.3 Before their assembly, the inner surface of the casing wall is
Covered with a backing layer 15 of expandable silicic acid composition, the backing layer 15 is substantially a hydrated alkali metal silicate, such as sodium or potassium silicate, containing 10 to 40 parts by weight of water. Consists of.

Since the panels may be subjected to impact forces during use, the silicate backing layer may be mechanically reinforced by incorporating asbestos or glass fibers into the silicate compound in an amount of up to 30% by weight. It's advantageous.

A non-combustible insulating material such as bentonite or diatomaceous earth may be included in the silicate solution in an amount not exceeding 20 parts by weight of the hydrated silicate.

The above-described backing composition is applied by any suitable means onto the inner surface of the casing wall member, and is applied to a 1/3 inch (3,175 m
m) to 1/4 (6,35 mm) inch thick layer.

Evaporation of excess water from the silicate composition solidifies and secures the composition to the inner surface of the casing member.

Evaporation of water from the silicate composition may be accelerated by applying mild heat not exceeding 90°C.

Other methods of forming the inner lining layer include laying single or double layers of loosely woven fiberglass or asbestos on the sheet metal casing wall, and sodium silicate until the desired thickness of the silicate layer is obtained. Apply the solution at intervals.

The coating thus formed is desirably compressed to reduce its thickness.

n) The pressure to compress the IJum silicate coating onto the inner sheet metal wall member may be obtained by pressure rollers or by compressing the composition and the casing wall member between cooperating clamp plates of a suitable press. It can also be obtained by

In a third method, preformed plate panels of silicic acid composition are cut to shape and secured to the inner wall surface of the casing member, such as by epoxy cement.

The wall elements having their inner surfaces coated with a layer of silicate composition by one of the methods described above are then assembled and secured together by suitable metal stators 16.

Welding is not recommended. This is because heat causes premature expansion of the backing composition.

The lined casing is then filled with polyurethane or other polymeric foam resin 18, the liquid component of which is introduced into the hollow interior through suitable openings in accordance with well-known techniques.

The fire-resistant insulated panel structure provided by the above-described laminate of metal, silicic acid composition, and foam polymer resin provides excellent insulation at ambient temperatures as low as 200°F (approximately 93°F).
Exhibits excellent fire resistance when subjected to temperatures exceeding 3°C.

If a fire were to occur in a building on one side of the panel, at temperatures of 100° C. to 150° C., the silicate backing material would soften and its water of crystallization would begin to evaporate.

The material foams, expands, and all water is expelled.
When.

Forming a relatively thick, rigid wall of porous pumice-like insulation between the i-casing and the polyurethane.

In a modified form, the foamable silicic acid material blocks the flow of heat to the urethane core in the panel.
=Ten↓7-8h□6'Mfs' When the heat on one side of the panel is of sufficient intensity and duration to pass through the silicate barrier 15 and cause the adjacent foam plastic core 18 to disintegrate. A void or passageway is formed between these layers, as shown at 19 in FIG.

The gases generated from the decomposing plastic in this zone are discharged through the casing opening 13.

The gas releases harmless products that may ignite and burn.

The wall panels of the present invention are described as employing sheet metal as the material of the external casing or jacket structure, and the panels are required to withstand flame and high heat conditions for a period of three hours or more. In some cases (current conditions for A grade standard doors or panels) sheet metal is preferred, but in less stringent conditions a sheet metal casing is not required.

In cases where one hour or less of fire protection is sufficient,
The casing may be constructed from a strong sheet material constructed from polyvinyl chloride, or other suitable resin, or fiberglass sheets.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a door or panel of the present invention, FIG. 2 is a fragmentary cross-sectional view of the panel taken along line 2-2 in FIG. 1, and FIG. 3 is a flame and heat acting on one side of the panel. FIG. 4 is a fragmentary cross-sectional view taken along line 4--4 of FIG. 1; 5: External wall, 6: Internal wall, 7: Upper groove strip, 8:
Lower groove strip, 10: edge flange, 13: ventilation opening, 14: polyethylene film, 15: lining 96
．． 18: Polyurethane or other polymeric resin.

Claims (1)

Claims: 1. A lamellar material casing having an inner wall, an outer wall, a top wall, a bottom wall, and side walls, and lined with a hydrous alkali silicate layer substantially completely lining the inner surface of the casing. an injected core of polymeric foam resin filling the interior of the casing, said alkali silicate layer being reinforced with asbestos, glass fiber or other reinforcement, said alkali silicate being a sodium silicate layer; or fire-resistant low-temperature insulation panels made of potassium silicate. 2. A method of manufacturing a fire-retardant low-temperature insulation panel, comprising the steps of forming a sheet material into a casing wall member having an inner surface and an outer surface, and lining said inner surface with a layer of an expandable alkali silicate composition. inner wall, outer wall, top wall, bottom wall,
assembling the lined wall member to form a substantially fully lined hollow casing having sidewalls; and filling the hollow casing with a polymeric in-situ foamed core material. , the expandable alkali silicate composition layer is reinforced with asbestos, glass or other reinforcing material, and the alkali silicate is sodium silicate or potassium silicate. Production method. 3. Lining the inner surface of the casing wall member by forming the expandable alkali silicate composition layer into a preformed sheet and placing the formed sheet on the inner surface of the casing wall member. A method for manufacturing a fireproof low-temperature insulation panel according to claim 2.