JP2006275090A - Fire prevention division penetrating part structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fire prevention division penetrating part structure, easy in construction at a job site, for applying a resin-coated steel pipe superior in anti-corrosiveness to a fire prevention division penetrating part, without using a material of a large environmental load. <P>SOLUTION: This fire prevention division penetrating part structure is blocked up by filling mortar in a void between a through-hole and a pipe by penetrating the pipe through the through-hole of a partition member 1 for partitioning a fire prevention division of a building. A pipe of at least a division penetrating part and a range of 30 mm on its both outside, is a polyethylene-coated steel pipe 4, and the polyethylene-coated steel pipe has a polyethylene layer having a melt flow rate of 0.6 or less on the outside of the steel pipe having the thickness of 5.9 mm or less and having an outer diameter of 116 mm or less. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a structure of a penetrating portion when a gas pipe penetrates a floor surface or a wall surface forming a fire prevention section of a building.

There are many cases where polyethylene-coated steel pipes are used as pipe materials that are usually used for gas pipes because they are excellent in strength and corrosion resistance and do not contain materials with high environmental impact such as PVC. Conventionally, for indoor use, use has been limited in terms of fire resistance of the penetration part of the fire prevention compartment. Although it is possible to use a metal tube, which is a non-combustible material, in the fireproof compartment penetrating portion, there are problems in terms of corrosion resistance and the like.
On the other hand, various types of fire protection methods have been proposed for applying a piping material made of a combustible material such as a polyethylene pipe to a fire protection compartment penetration site. For example, a thermal expansive insulation material is filled between the concrete that makes up the floor or wall and the pipe pipe material, and once a fire breaks out, it expands and a gap passes through the floor or wall. (Patent Document 1), and the piping material penetrating through the fire prevention compartment is covered with glass wool heat insulating material, and the heat resistance and heat insulation by heating the glass wool heat insulating material side of the piping material covered with glass wool heat insulating material The main ones (Patent Document 2) provided with a heat-expandable material for forming a layer.

JP-A-7-39598 JP 2001-303692 A

  However, these conventional methods require a lot of construction at the site, and the work space at the actual site is often narrow, which is not necessarily efficient and increases the labor and construction cost during construction. There were drawbacks.

  The present invention relates to a structure of a fireproof compartment penetration portion that is easy to construct on site for applying a resin-coated steel pipe excellent in corrosion resistance without using a material having a large environmental load to the fireproof compartment penetration portion. .

  As a result of intensive studies on the fireproof performance of the partition through portion and the structure and material of the resin-coated steel pipe, the present inventors have found that the above problem can be solved by the following method. In other words, in the structure of the penetration part when the pipe penetrates the floor or wall that forms the fire prevention compartment of the building, it is larger than the pipe that tries to penetrate the partition member that partitions the compartment such as the floor or wall. The structure is a structure in which a hole is made, the polyethylene-coated steel pipe is penetrated, and the gap is backfilled with mortar. Further, the polyethylene-coated steel pipe used at least in the section through portion and the range of 30 mm on both sides has a thickness of 5.9 mm or less. If the outer diameter of the steel pipe is 116 mm or less and the outer layer has a polyethylene layer with a melt flow rate of 0.6 or less, this fire-blocking section penetration is one-hour flame-shielding performance as stated in the Building Standards Law Enforcement Ordinance. Equivalent to the fire prevention area equivalent to the one-hour fire resistance performance of the Japan Fire Fighting Equipment Safety Center It proved to be a level capable of sufficiently applicable to penetrate the pipe firestop co housing compartment such as referred in Boho Enforcement Order.

  If the fireproof compartment penetrating portion of the structure of the present invention is used, even if one side of the compartment penetrating portion is heated due to a fire, the coating resin does not flow down completely due to the temperature rise, and it is appropriate between the steel pipe and the mortar of the compartment penetrating portion. In order to form a burning husk, there is no gap through which a fire can pass.Furthermore, according to the present invention, the steel pipe is always covered with polyethylene unless a fire occurs, so that it has excellent corrosion resistance. ing.

  The fireproof compartment penetrating structure of the present invention uses a coated steel pipe that does not contain a material with high environmental impact such as polyvinyl chloride, and has excellent strength and corrosion resistance. The labor and construction cost at the time are kept low, and it has sufficient fire resistance.

  Various preferred embodiments of the present invention will be described below.

(Partition penetration structure)
Structure of the fire-blocking section through which piping penetrates the floor or wall of the building that forms the fire-blocking area such as the fire-resisting section as defined in the Building Standard Law Enforcement Ordinance and the Fire Fighting Law Enforcement Ordinance In the above, a circular hole 40 to 80 mm larger than the outer diameter of the pipe to be passed through the partition member partitioning the floor or the wall or the like is drilled, and the polyethylene-coated steel pipe described below is penetrated, and the gap is formed with mortar. It is a backfilled structure. Moreover, in order to ensure fireproof performance, ease of construction, and construction accuracy, it is necessary to apply the polyethylene-coated steel pipe described below over at least the section through portion and the range of 30 mm on both sides. Of course, the polyethylene-coated steel pipe having a length longer than this may be used in consideration of the ease of construction and the corrosion resistance of the pipe.

  The partition member here may be a reinforced concrete / ALC plate (lightweight cellular concrete plate) or the like that usually constitutes a fire prevention compartment or a cohabitation compartment, and the thickness is usually 100 mm or more. Also, the mortar that fills the gap formed between the pipe and the partition member may be a known one that is usually used, and is usually composed of fine aggregate and water composed of Portland cement and river sand or mountain sand, and the weight of cement: sand. Those prepared in a ratio of 1: 2 to 1: 3 can be used. The ratio of the cross-sectional area of the polyethylene-coated steel pipe to the area of the opening is 46% or less, preferably 41% or less.

  When the application of the above polyethylene-coated steel pipe is too short, or when the ratio of the cross-sectional area of the polyethylene-coated steel pipe to the area of the opening is too large, the fire prevention characteristics of the through portion cannot be expressed, and the expected effect cannot be obtained. .

  Moreover, it is desirable that the separation distance between the holes provided in the partition for penetrating the pipe is 200 mm or more.

(Steel pipe)
The steel pipe used in the present invention may be a steel pipe having an outer diameter of 116 mm or less and a wall thickness of 5.9 mm or less, particularly preferably an outer diameter of 20 mm or more and 90 mm or less and a wall thickness of 2.4 mm or more and 5.5 mm or less. Is desirable. Blasting, pickling, chemical conversion, plating, or thermosetting primer coating with a thickness of 200 μm or less may be applied to the outer surface of the steel pipe, and blasting, pickling, chemical conversion on the inner surface of the steel pipe. , Plating treatment, thermosetting primer coating treatment, etc. If the outer diameter of the steel pipe exceeds 116 mm, or if the wall thickness exceeds 5.9 mm, the amount of heat transferred to the opposite surface through the steel pipe increases when heated from one side of the compartment, and the back surface temperature becomes high. It will pass.

(Polyethylene coating)
Polyethylene used for the coating layer is a known general-purpose resin that is polymerized with ethylene as a main component, but propylene, butene, hexene, or octene is used as a copolymerization monomer to improve the performance as a coating layer. A copolymer using a commonly called α-olefin may be used. However, the melt flow rate is 0.6 or less, more preferably 0.3 or less, in terms of fire resistance of the partition through portion. The lower limit of the melt flow rate is not particularly limited, but is practically about 0.05. The melt flow rate can be determined by an ordinary method for measuring the melt mass flow rate of polyethylene, and can be measured by the method defined in JIS K6922-1 (measurement temperature 190 ° C., load 2.16 kg). The unit is g / 10 minutes.

  In addition, the resin composition may be mixed with other resins as long as the performance of the present invention is not impaired. If necessary, an antioxidant, an ultraviolet absorber, a light-resistant stabilizer, a flame retardant, a pigment, Additives such as colorants, fillers, lubricants, antistatic agents, tackifiers and the like can be added.

The thickness of the polyethylene layer is about 0.6 to 2.4 mm, preferably about 1.4 to 2.0 mm.
In order to firmly bond the steel pipe and the polyethylene layer, an adhesive layer may be interposed between the steel pipe or the steel pipe coated with a primer and the polyethylene layer, and the adhesive layer is modified with maleic anhydride. Polyethylene or the like can be used, but the thickness of the adhesive layer is desirably 0.3 mm or less. If the thickness of the adhesive layer exceeds this, the fireproof property of the penetrating portion cannot be sufficiently exhibited, and it becomes difficult to obtain the expected effect. On the other hand, it is preferable that the thickness is at least 0.1 mm or more in order to exhibit an adhesive function and to form a uniform layer.

  Moreover, the thickness of the coating layer formed in the outer side of a steel pipe should just be 2.5 mm or less in total which put the polyethylene layer and the adhesive bond layer together. If it exceeds 2.5 mm, the fireproof properties of the penetrating part cannot be sufficiently exhibited, and the expected effect may be difficult to obtain.

(Coating method)
The coating of the resin on the steel pipe may be performed by a conventional method. The acid-modified polyethylene and polyethylene may be sequentially extruded and coated on the outside of the steel pipe, or may be co-extruded at a time. Alternatively, each may be powder-coated to form a coating layer.

  Hereinafter, the compartment penetrating structure of the present invention will be described using examples, but the present invention is not limited to the following examples.

(Examples 1 to 11)
In advance, the outer surface of the steel pipe shown in Table 1 was blasted, and a thermosetting epoxy primer was applied to the outside thereof in a thickness of 10 to 20 μm. The steel pipe was heated to 190 ° C. by induction heating to cure the primer. The polyethylene shown in Table 1 and maleic anhydride-modified polyethylene having a melting point of 125 ° C. and a density of 0.936 g / cm 3 are melted in an extruder and coextruded into a cylinder from a crosshead mold so that the acid-modified polyethylene is on the inside. Then, a coating layer having a thickness shown in Table 1 was formed on the outer surface of the steel pipe. In this way, a polyethylene-coated steel pipe was produced. The obtained polyethylene-coated steel pipe was cut to a length of 1400 mm.

  A reinforced concrete plate having a length of 800 mm, a width of 1600 mm, and a thickness of 100 mm was produced. At this time, the holes having the dimensions shown in Table 3 were prepared in the vicinity of the center of the reinforced concrete plate so as to be separated from each other by 200 mm or more. After curing for 110 days, a polyethylene-coated steel pipe was passed through the center of the hole, and the gap with the concrete plate was backfilled with mortar to produce a partition member. For mortar, ordinary Portland cement and sand were mixed at a weight ratio of 1: 3. Thereafter, the specimen was cured for 110 days to obtain a test piece for the section penetration portion.

  In addition, the coated steel pipe is set so that one side is 1000 mm longer than the concrete plate surface and the opposite side is 300 mm longer than the plate surface, and the end of the coated steel tube on the side protruding 300 mm from the plate surface is set. It was blocked.

(Comparative Examples 1-4)
Using the polyethylene shown in Table 2, a polyethylene-coated steel pipe having a coating layer having the thickness shown in Table 2 was produced in the same manner as in Examples 1 to 11, and using this, the same as in Examples 1 to 11 was used. The test body of the division penetration part was manufactured by the method. However, the holes opened in the reinforced concrete plate were the sizes shown in Table 3. In Comparative Examples 1 and 2, the two holes were separated from each other by 300 mm or more.

  About the compartment penetration part test body of Examples 1-11 and Comparative Examples 1-4 which were obtained in this way, fireproof property was investigated and evaluated.

<Fireproof>
The side where the length of the steel pipe of the manufactured section penetration part test piece was 300 mm was set as the heating side, and a part separated by 160 mm or more from the mortar backfill part on the heating side was covered with a 25 mm thick ceramic plate to prevent explosion. This zone penetration part test specimen was subjected to a 1 hour fire resistance test and its evaluation in accordance with the “Fireproof Test Method for Fire Protection Zone Through Piping” provided by the Japan Fire Department Safety Center Foundation. The evaluation results are shown in Table 4. Here, the initial back surface temperature is the temperature of a mortar backfill portion that is 10 mm away from the coated steel pipe penetrating portion on the non-heated side surface of the partition member, and is measured at four points at intervals of 90 degrees in the circumferential direction, which is the maximum temperature. Moreover, the maximum back surface temperature measured the same position as the initial back surface temperature during the test and 30 minutes after the test, and showed the highest temperature among them.

<Evaluation>
In the evaluation, (a), (b) and (c) in Table 4 are “none”, (d) is less than 100 mm, the maximum back surface temperature does not exceed 210 ° C., and the initial back surface temperature is reached. The case where the temperature which added 180 degreeC was not exceeded was made favorable, and other than that was made into defect "x". Even in the case of good, the case where (d) in Table 4 is less than 80 mm is “◎”, the case of 80 mm or more and less than 95 mm is “◯”, and the case of 95 mm or more and less than 100 mm is “Δ”.

  From the results of Table 4, Examples 1 to 11 were good, while Comparative Examples 1 to 4 were bad.

  INDUSTRIAL APPLICABILITY The present invention is suitable for a structure of a penetration portion when a gas pipe penetrates a floor surface or a wall surface forming a fire prevention section of a building.

It is a figure which shows typically an example of the division penetration structure of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Partition partition member 2 ... Hole 3 ... Mortar, mortar backfill part 4 ... Polyethylene covering steel pipe 5 ... Steel pipe 6 ... Primer layer 7 ... Adhesive layer 8 ... Polyethylene layer

Claims (2)

A fire-blocking section penetrating structure in which a pipe is inserted into a through-hole of a partitioning member that partitions a fire-proof section of a building, and a gap between the through-hole and the pipe is filled with mortar, and at least the section penetrating section and its outer sides 30 mm. The pipe in the range is a polyethylene-coated steel pipe, and the polyethylene-coated steel pipe has a polyethylene layer having a melt flow rate of 0.6 or less on the outside of a steel pipe having a wall thickness of 5.9 mm or less and an outer diameter of 116 mm or less. A structure for penetrating a fire prevention compartment, characterized in that. The polyethylene-coated steel pipe has an adhesive layer between the polyethylene layer and the outer surface of the steel pipe, and the total thickness of the coating layer including the polyethylene layer and the adhesive layer is 2.5 mm or less. The fire compartment penetrating structure as described.

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