A fire performance test assembly method for large diameter HDPE pipes

Abstract

The present invention relates to a fireproof performance test assembly method for a large-diameter HDPE pipe. The test is performed using a HDPE board of the same type with the same radial material thickness as the HDPE pipe. First, a plurality of heat-insulating nail fixing ends are arranged on the fire-receiving surface of the HDPE board at a certain interval, and then a fireproof material is laid on the fire-receiving surface. Then, an aluminum thin layer material is laid on the fireproof material. A hole is opened at a position corresponding to the heat-insulating nail fixing end of the aluminum thin layer material, and a heat-insulating nail is nailed into the heat-insulating nail fixing end at the opening to fix the fireproof material and the aluminum thin layer material. The present invention can not only truly reflect the protective effect on the actual large-diameter HDPE pipe, but also meet the relevant installation requirements of the combustion performance test method, can truly reflect the overall combustion performance of the composite material after protection, and also has the characteristics of beauty and safety.

Description

Technical Field

[0001] The invention belongs to the fireproof performance test technology of building materials, and specifically relates to a fireproof performance test assembly method for a large-diameter HDPE pipe. Background Art

[0002] Since the outer diameter of the HDPE pipe in the important plant water system of the actual nuclear power plant is 812.8mm, according to the provisions of the "Classification of Combustion Performance of Building Materials and Products" (GB 8624-2012), when the outer diameter of the tubular insulation material is greater than 300mm, it must be tested according to the combustion performance test method of flat-plate materials. The existing method for fire protection of HDPE pipes is usually to wrap it with fireproof cotton, cover the outer layer with a metal layer, and then use iron wire to tie it tightly. This method is not suitable for large-scale flat HDPE for fire performance testing. The fire-exposed side of the HDPE board is fire-protected, and the back-fire side is not protected. If iron wire is used for tying, the iron wire will quickly transfer the high temperature on the fire-exposed side to the back-fire side, causing damage to the HDPE material; if iron wire is not used for tying, it is difficult to fix the HDPE cotton and the metal layer, which can easily cause the fireproof material on the fire-exposed side to fall off due to heat, and it is impossible to accurately characterize the effect of the material for pipeline fire protection. Summary of the invention

[0003] The purpose of the present invention is to provide a fire retardant performance test assembly method for large-diameter HDPE pipes in view of the deficiencies in the prior art, so as to achieve stable assembly of each layer of fire retardant material during the test.

[0004] The technical solution of the present invention is as follows: a method for assembling a fireproof performance test of a large-diameter HDPE pipe, wherein a HDPE board of the same type with a radial material thickness consistent with that of the HDPE pipe is used for the test, a plurality of insulation nail fixing ends are firstly arranged on the fire-receiving surface of the HDPE board at a certain interval, and then a fireproof material is laid on the fire-receiving surface, and then an aluminum thin layer material is laid on the fireproof material, holes are opened at positions of the aluminum thin layer material corresponding to the insulation nail fixing ends, and insulation nails are nailed into the insulation nail fixing ends at the openings to fix the fireproof material and the aluminum thin layer material.

[0005] Furthermore, in the fire resistance test assembly method for large-diameter HDPE pipes as described above, the side edges of the aluminum thin layer material are bent and coated on the side surfaces of the HDPE board.

[0006] Furthermore, in the fire resistance test assembly method for large-diameter HDPE pipes as described above, the fixing ends of the plurality of insulation nails are bonded to the fire-exposed surface of the HDPE board using high-temperature resistant inorganic glue.

[0007] Furthermore, in the fire resistance performance test assembly method of the large-diameter HDPE pipe as described above, the fixed ends of the plurality of insulation nails are fixed on the fire-exposed surface of the HDPE board in a matrix form.

[0008] Furthermore, in the fire retardant performance test assembly method for large-diameter HDPE pipes as described above, the fire retardant material is inorganic flexible fire retardant cotton, and the thickness of the fire retardant cotton is consistent with the thickness of the fire retardant material on the actual HDPE pipe; the thickness of the aluminum thin layer material is consistent with the thickness of the aluminum thin layer material on the actual HDPE pipe.

[0009] Furthermore, the fireproof cotton is aluminum silicate cotton.

[0010] Furthermore, in the fire resistance performance test assembly method of the large-diameter HDPE pipe as described above, the insulation nails and the insulation nail fixing ends are made of aluminum.

[0011] Furthermore, in the fire resistance test assembly method of the large diameter HDPE pipe as described above, the spacing and number of the insulation nails should be designed to avoid excessive heat from being conducted from the fire-exposed surface to the HDPE board through the insulation nails while ensuring the fixing strength.

[0012] The beneficial effects of the present invention are as follows: the present invention covers and assembles HDPE plastic sheets, which can not only truly reflect the protective effect on actual large-diameter HDPE plastic pipes, but also meet the relevant installation requirements of the combustion performance test method, can truly reflect the overall combustion performance of the protected composite material, and also has the characteristics of beauty and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the HDPE board used in the assembly method of the present invention;

[0014] Figure 2 It is a cross-sectional view of the test sample assembled by the method of the present invention. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0016] The fire performance test of the large diameter HDPE pipe described in the present invention is conducted by using the same type of HDPE board with the same radial material thickness as the HDPE pipe. At present, the installation method for fire protection of HDPE pipes is relatively mature, usually a layer of flexible fire protection material is coated on the outside of the pipe, and then a layer of aluminum thin layer material is coated on the outer layer. However, for large-scale flat HDPE boards, it is not suitable to use wire bundling to assemble and fix the flexible fire protection material and the aluminum thin layer material in the test. The present invention proposes a specific solution to this problem.

[0017] The fireproof material assembly method provided by the present invention is as follows: Figure 1 , Figure 2 As shown, a plurality of insulation nail fixing ends 2 are firstly arranged on the fire-exposed surface of the HDPE board 1 at a certain interval, and then a fireproof material 3 is laid on the fire-exposed surface, and then an aluminum thin layer material 4 is laid on the fireproof material 3. A plurality of holes are opened at positions of the aluminum thin layer material corresponding to the insulation nail fixing ends, and insulation nails are nailed into the insulation nail fixing ends at the openings to fix the fireproof material and the aluminum thin layer material.

[0018] like Figure 2 As shown, the front (fire-exposed side) and side surfaces of the HDPE board 1 are covered with fireproof material 3 and aluminum thin layer material 4. The aluminum thin layer material 4 reduces the splicing gap of the fireproof protective material by covering the front surface and bending the side.

[0019] The aluminum thin layer material 4 is fixed on the HDPE sheet at a certain interval through aluminum insulation nails. Specifically, several aluminum insulation nail fixing ends 2 are bonded to the fire-receiving surface of the HDPE sheet with high-temperature resistant inorganic glue, and several insulation nail fixing ends are distributed in a matrix form, and then the fireproof material 3 (fireproof cotton) is paved, and then the aluminum thin layer material 4 with openings at the corresponding position is covered, and finally the aluminum insulation nails are fixed on its surface. The spacing of the insulation nail fixing ends should not be too dense, and too many insulation nails will form too many thermal bridges, causing heat to be transferred from the fire-receiving surface to the HDPE board through a large number of insulation nails; but the number of insulation nails should not be too small, and too few may not be able to stably fix the fireproof cotton. Since the fireproof cotton has a certain weight, if a small number of insulation nails are softened by heat in the case of direct fire, its bottom may also fall off from the surface of the HDPE board. Therefore, the design of the spacing and number of insulation nails should be based on the actual situation, while ensuring the fixing strength, to avoid excessive heat from the fire-receiving surface through the insulation nails to the HDPE board. Usually, the size of the fixed end of the insulation nail can be designed to be about 3cm×3cm square, and the shape can be rectangular or circular.

[0020] The present invention uses inorganic glue to bond the fixed end of the heat preservation nail, which can truly reflect the fire protection effect. If the fire protection effect is poor, the temperature of the interface between the fireproof cotton and the HDPE sheet will inevitably rise significantly, and the heat preservation nails that are fixed by bonding will fall off. The thickness of the fireproof cotton used in the test is consistent with the thickness of the fireproof material on the actual HDPE pipe; the thickness of the aluminum thin layer material is also consistent with the thickness of the aluminum thin layer material on the actual HDPE pipe.

[0021] Example

[0022] The HDPE board is composited with fireproof cotton and aluminum skin, and the three are tightly fixed together with insulation nails. Specifically, the fixed end of the aluminum insulation nail is bonded to the fire-exposed side of the HDPE board with a high-temperature resistant inorganic glue, and then the fireproof cotton is laid, and then covered with an aluminum thin layer material with openings at the corresponding position of the fixed end, and finally the aluminum insulation nails are fixed on its surface to form a fireproof cotton composite high-density polyethylene board. In this embodiment, the inorganic glue is a high-temperature resistant inorganic glue, and the fireproof cotton has a density of 130kg / m 3 From the fire-exposed side to the back-fire side, there are 0.5mm thick aluminum skin, 30mm thick aluminum silicate wool and 75mm thick HDPE board.

[0023] Using propane gas as fuel, a monomer combustion test was carried out on the aluminum silicate wool composite high-density polyethylene board. Propane gas generates a heat output of (30.7±2.0) kW through a sandbox burner. Through a 20-minute test process, the combustion performance parameters including heat release, smoke production, lateral flame propagation, and burning drips and particulate matter were recorded to evaluate the combustion performance of the sample. Among them, the smoke exhaust duct is equipped with an airflow sensor for measuring temperature, light attenuation, oxygen and carbon dioxide mole fractions, and pressure differences caused in the duct. The relevant values ​​can be automatically recorded and used to calculate the volume flow rate, heat release rate, and smoke production rate; for the performance parameters of lateral flame propagation and burning drips and particulate matter, they can be recorded by visual inspection. The corresponding data obtained from the test are listed in Table 1.

[0024] Table 1 Combustion performance parameters of aluminum silicate wool composite high-density polyethylene board monomer

[0025]

[0026] The above test results are far lower than the combustion performance of building materials B 1 (B) Class-related criteria (burning growth rate index ≤ 120 W / s, total heat release in 600 s ≤ 7.5 MJ, lateral flame spread does not reach the edge of the long wing of the specimen).

[0027] Therefore, the use of aluminum silicate wool and aluminum skin of the thickness of this embodiment in combination with the high-density polyethylene board for fire protection can effectively improve the combustion performance of the high-density polyethylene board, and can reach B 1 (B) Level.

[0028] The present invention solves the problem of lack of test assembly method for large-diameter HDPE pipes after fire protection measures are taken. On the one hand, each layer of fireproof material can be firmly assembled during the test and will not fall off due to heat during the fire. On the other hand, this installation method can also accurately reflect the fire protection effect of the pipe-shaped material in actual application.

[0029] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0030] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A fire performance test assembly method for large diameter HDPE pipes, characterized in that: The same type of HDPE board with the same radial material thickness as the HDPE pipe is used for testing. First, a number of insulation nail fixed ends are set on the fire-exposed surface of the HDPE board at a certain interval. The several insulation nail fixed ends are bonded to the fire-exposed surface of the HDPE board with high-temperature resistant inorganic adhesive. Then, a fireproof material is laid on the fire-exposed surface. The fireproof material is inorganic flexible fireproof cotton. The thickness of the fireproof cotton is consistent with the thickness of the fireproof material on the actual HDPE pipe. Then, an aluminum thin layer material is laid on the fireproof material. The thickness of the aluminum thin layer material is consistent with the thickness of the aluminum thin layer material on the actual HDPE pipe. Holes are opened at positions corresponding to the insulation nail fixed ends of the aluminum thin layer material. Insulation nails are nailed into the insulation nail fixed ends at the openings to fix the fireproof material and the aluminum thin layer material. The insulation nails and the insulation nail fixed ends are made of aluminum.

2. The method for assembling a large diameter HDPE pipe for fire resistance test according to claim 1, characterized in that: The side edges of the aluminum thin layer material are bent and coated on the side surfaces of the HDPE plate.

3. The method for assembling a large diameter HDPE pipe for fire resistance test according to claim 1, characterized in that: The fixing ends of the plurality of heat-insulating nails are fixed on the fire-exposed surface of the HDPE board in a matrix form.

4. The method for assembling a large diameter HDPE pipe for fire resistance test according to claim 1, characterized in that: The fireproof cotton is aluminum silicate cotton.

5. The method for assembling a large diameter HDPE pipe for fire resistance test according to claim 1, characterized in that: The spacing and number of the insulation nails should be designed to ensure the fixing strength and avoid excessive heat from being transferred from the fire-exposed surface to the HDPE board through the insulation nails.

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