JP5305875B2 - Thermal insulation structure of floating tank roof - Google Patents

Description

  The present invention relates to a heat insulating structure for a floating tank roof.

  In general, a liquid storage tank such as a heavy oil storage tank is formed of a floating tank that floats and covers a roof portion on a liquid surface whose height changes according to a change in the storage amount. The liquid to be stored needs to be stored under a predetermined temperature (for example, when it is necessary to keep the liquid warm or warm and adjust the viscosity within a predetermined range). Things have been done.

  For example, conventionally, as shown in FIG. 4, a plurality of plate-like heat insulating members 3 are fixed to each other on the upper surface of the floating tank roof portion 1, and each of the heat insulating members 3 arranged in a waterproof manner is formed of a fluororesin or the like. There is a heat insulating structure that covers the sheet 10 and adheres the ends of the adjacent waterproof sheets 10 to each other at the joints between the heat insulating members 3 arranged, or bonds them through the connecting waterproof sheet 11 (for example, , See Patent Document 1).

JP-A-6-345180 (FIG. 1)

  In the case of the conventional heat insulating structure described above, there is a construction problem that it takes much time and labor to bond the waterproof sheets 10 and 11 together. Moreover, since the floating tank roof part 1 is generally made of a metal plate, it expands and contracts with changes in temperature or vibrates with changes in liquid level. 10 and 11 and the adhesion part of the waterproof sheets 10 and 11 cannot follow, and there exists a problem that an adhesion part remove | deviates or the waterproof sheets 10 and 11 tear.

  Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a heat insulating structure that can easily follow the fluctuation of the roof portion without taking time and labor for construction.

The first characteristic configuration of the present invention is that a plurality of plate-like heat insulating members are fixed side by side on the upper surface of the floating tank roof portion installed in a state of floating on the liquid surface of the liquid storage tank, and a plurality of the heat insulating members arranged side by side are fixed. over the front surface of the joint portion between those adjacent and their, Ri spray layer of polyurethane rubber with a waterproof Oh covers continuously, the floating tank is heavy oil storage tank, the polyurethane rubber An antistatic protective layer is provided on the surface side of the spray layer .

According to the first characteristic configuration of the present invention, the polyurethane rubber spraying layer covering the front side surface of the joint portion between the adjacent heat insulating members and the adjacent ones can be constructed in a short time and the work period can be shortened. In addition, due to the elasticity of polyurethane rubber, it is easy to follow expansion and contraction due to temperature changes of the roof of the metal plate and vibration accompanying vertical movement, and has high strength and covers the heat insulating member and joints over a long period of time. be able to. In addition, the waterproof property of the polyurethane rubber that continuously covers the heat insulating member and the front side of the joint can prevent rainwater from entering between the heat insulating member and the metal roof portion. It is possible to prevent deterioration due to corrosion and a decrease in the heat insulating property of the heat insulating member, and maintain the storage performance for the stored liquid over a long period of time.
Further, the surface side of the polyurethane rubber spray layer is protected by the antistatic protective layer, so that the stored liquid can be safely stored even if it is a flammable liquid.

According to a second characteristic configuration of the present invention, the heat insulating member is fixed to the floating tank roof portion with an adhesive, and the polyurethane rubber spray layer is made of a two-component curing type polyurethane rubber elastomer, tensile strength 10 N / mm ² or more, the tear strength of 50 N / m m or more on the elongation percentage of 200% or more, where those having physical properties within the gel time 20 seconds.

According to the second characteristic configuration of the present invention, the heat insulating member is stably fixed to the floating tank roof portion by an adhesive, and the polyurethane rubber spraying layer covering the heat insulating member is elastic by the two-component curable polyurethane rubber elastomer. High heat insulation layer can be easily formed.
Moreover, tensile strength 10 N / mm ² or more, the tear strength of 50 N / m m than on, the use of elongation of 200% or more of polyurethane rubber, even when the roof portion of the metal is formed by generally iron , Can sufficiently follow the expansion and contraction accompanying the temperature change.
In addition, since it has physical properties within 20 seconds of gelation time, it hardens in a short time after spraying and is difficult to sag against the sprayed surface or uneven surface in the vertical direction, and a uniform and stable coating layer with a large thickness is provided. Can be formed.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the parts indicated by the same reference numerals as those in the conventional example indicate the same or corresponding parts.

Figure 1 is a schematic diagram showing a fuel oil storage tank as flow computing tanks, oil storage tanks, as an outer wall, and a roof section 1 and the shell 2 formed by joining a large number of steel sheets by welding. The roof portion 1 constitutes a circular floating ceiling B having a diameter of about 40 m to 67 m. That is, the floating ceiling B seals between the roof portion 1 formed of a steel deck having a thickness of about 4.5 to 6 mm, the pontoon 4 provided on the outer peripheral portion thereof, and the pontoon 4 and the tank peripheral wall 2. The seal member 5 is provided, and in a state of floating on the stored heavy oil C, the seal member 5 is provided so as to move up and down according to the increase or decrease in the stored heavy oil amount. In addition, the roof part 1 is provided with a gradient toward the drain port 19 provided near the center thereof, and intrusion water such as rainwater in the roof unit 1 flows from the drain port 19 along the gradient to the drain port 19. The drainage hose 20 is connected to the outside of the storage facility A through the drainage hose 20 so that it does not stay on the roof portion 1 for a long time.

As shown in FIG. 2, the roof portion 1 is formed by joining a large number of steel plates 6 having a thickness of about 4.5 to 6 mm by welding, and about 200 mm with a weld line interposed between the steel plates 6. Each of the steel plates 6 is thermally insulated by bonding and fixing the heat insulating member 3 made of flame-retardant 30-fold foamed polyethylene and having a space of about 25 mm.
And the spraying layer 8 of the polyurethane rubber which has waterproofness (based on JIS A6021 type 1) is continuous over the adjacent thing of the said heat insulation member 3 arranged side by side, and the front side surface of the joint part 7 between them. Is covered.

The heat insulating member 3 is fixed via a chloroprene adhesive 12 after a primer 9 made of an epoxy-modified urethane resin is applied to the upper surface of a steel plate 6.
The polyurethane rubber spraying layer 8 is made of a material in which a special amine is mixed as a catalyst with a two-component curing type polyurethane rubber elastomer having an isocyanate as a main component and a polyol as a curing agent. And self-extinguishing.
Further, an antistatic protective layer 13 is formed on the surface side of the spray layer 8 by applying an antistatic paint.

The polyurethane rubber elastomer spray layer 8 of this embodiment has a Shore A hardness of 89, a tensile strength of 12 N / mm ² , a tear strength of 58 N / mm , an elongation of 380%, and a physical property that starts to gel from 15 seconds. there is, after all, in order to avoid damage to follow the vibration due to the elevation of the thermal expansion or roof section 1 of the steel plate 6, a tensile strength of 10 N / mm ² or more, the tear strength of 50 N / m m than on, elongation There is a need to have physical properties of 200% or more.
Furthermore, in order to form the spray layer 8 having a coating thickness of 2.0 kg / m ^{2 on} the uneven surface of the heat insulating member 3 and the joint portion 7 by spray coating, the physical properties within 20 seconds of gelation time are required. is necessary. In other words, the application amount of 1 mm thickness / m ² is 1 kg, and in order to form a spray layer of about 1 to 2 mm thickness, if it takes 20 seconds or more after spraying and gels, it will sag and spray with uniform thickness Therefore, in order to form a uniform spray layer on the concavo-convex portion, it is necessary to gel within 20 seconds.

Next, according to the construction flow shown in FIG. 3, first, the first step of inspecting the tank iron skin surface, then the second step of coating with the tank surface keren, the exposed iron plate (the steel plate 6 and its welded portion). The third step of applying the primer 9 to the second step, and the fourth step of applying the adhesive 12 to the 25 mm-thick heat insulating member 3 and sticking it to the underlying steel plate 6 (if there is a step, use double-sided tape together) ), 5th step of spray pump car placement and curing, 6th step of spraying ultra-fast curing polyurethane rubber elastomer uniformly (average thickness about 2mm) (the coating amount at this time is 2.0Kg / m ² , but welding And the seventh step of forming the antistatic protective layer 13 by applying a predetermined coating amount (0.2 Kg / m ² ) uniformly with a roller to form an antistatic protective layer 13 in sequence. To do.
In addition, as mentioned above, although the code | symbol was written in order to make contrast with drawing convenient, this invention is not limited to the structure of an accompanying drawing by this entry. In addition, it goes without saying that the present invention can be carried out in various modes without departing from the gist of the present invention.

Schematic general view described in the embodiment of the present invention The principal part longitudinal cross-sectional view which shows embodiment of this invention Process diagram showing construction flow Longitudinal sectional view of the main part of the conventional

DESCRIPTION OF SYMBOLS 1 Roof part 3 Heat insulation member 7 Joint part 8 Spraying layer 13 Antistatic protective layer

Claims (2)

A plurality of plate-like heat insulating members are fixed side by side on the upper surface of the floating tank roof portion installed in a state of floating on the liquid surface of the liquid storage tank, and a plurality of the heat insulating members arranged side by side and a joint portion therebetween. over the front surface of, Ri spray layer of polyurethane rubber with a waterproof Oh covers continuously, the floating tank is heavy oil storage tank, on the surface side of the spray layer of said polyurethane rubber, charging Thermal insulation structure of the floating tank roof with a protective protective layer . The heat insulating member is fixed to the floating tank roof portion with an adhesive, and the polyurethane rubber spray layer is made of a two-component curing type polyurethane rubber elastomer, and has a tensile strength of 10 N / mm ² or more and is torn. strength 50 N / m m or more on the elongation percentage of 200% or more, the heat insulating structure of the floating tank roof according to claim 1, wherein those having physical properties within the gel time 20 seconds.

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