JPH03288097A - Manufacturing method of insulated transport pipe - Google Patents

Abstract

PURPOSE:To form a tube, insulating material and an armor tube into integrated structure by fixing inorganic insulating material at the periphery of the tube, winding separating material around thereon, inserting this into an armor tube, holding both concentrically in the raised state, and filling/solidifying a lightweight concrete-mortar composition between the separating material and the armor tube. CONSTITUTION:Inorganic insulating material 3 is fixed at the outer peripheral surface of a tube 2, and sheet like separating material 5 is wound around the outer peripheral surface of the inorganic insulating material 3. The tube 2 in this state is inserted into an armor tube 4, and these are held in the concentric state and supported being inclined by an appropriate angle. A cock body 7a is provided at the lower end of an annular space 7 formed between the separating material 5 and armor tube 4, and a lightweight concrete-mortar composition 6a is filled from the lower end through this cock body using a filling device 8 while replacing it with air existing in the annular space 7 and solidified. Lightweight concrete thermal insulating material 6 is thus formed so as to obtain simultaneously an insulated transport tube 1 formed of the tube 2, insulating material 3 and armor tube 4 into integrated structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an improvement in a method for manufacturing an insulated transport pipe for transporting high-temperature fluid.

[Summary of the Invention] The present invention provides a method for manufacturing an insulated transport pipe in which an inorganic heat insulating material is fixed to the outer circumferential surface of a main pipe, and the inorganic heat insulating material is inserted into an armored pipe to be integrated. The annular space is filled with a lightweight concrete/mortar composition so that no voids are left between the outer pipe and the heat insulating material.

[Prior Art] Conventionally, an insulated transport pipe in which a main pipe, an inorganic heat insulating material, and an outer pipe are integrated in advance is known. To manufacture this type of insulated transport pipe, for example, the main pipe is coated with an inorganic heat insulating material having an outer diameter smaller than the inner diameter of the outer pipe, and then a heat insulating inorganic filler is applied to the surface of the insulating material. A method has been adopted in which it is inserted into the exterior pipe and integrated.

[Problems to be Solved by the Invention] However, in the conventional manufacturing method described above, it is impossible to apply the filler uniformly, and as a result, a gap is created between the outer pipe and the insulation material, which causes the insulation to deteriorate. properties, pressure resistance,
In addition to decreasing impact resistance, because the main pipe, insulation material, filler material, and outer pipe are integrated, large thermal stress is generated in the insulation material due to temperature changes when the main pipe is used. If it becomes larger than the allowable value, serious performance defects such as destruction of the insulation material will occur. In addition, the manufacturing apparatus used to carry out the manufacturing method is expensive, complicated to operate, and requires a high level of skill.

[Object of the Invention] The present invention has been made in order to eliminate the drawbacks of the conventional manufacturing method described above, and is capable of manufacturing main pipes, heat insulating materials, etc. without reducing the heat insulating properties, pressure resistance, impact resistance, etc. The main object of the present invention is to provide a method for manufacturing an insulated transport pipe, which allows the outer pipe to have an integral structure and does not require a high level of skill.

[Means for Solving the Problem] The present invention fixes an inorganic heat insulating material to the outer circumferential surface of the main pipe of a transport pipe, wraps a separating material around the outer circumferential surface of the insulating material, and then attaches the inorganic heat insulating material and the separating material to the outer circumferential surface of the main pipe of a transport pipe. Insert the main pipe into the outer pipe, raise it up at the required angle while holding it concentrically, and pour the lightweight concrete/mortar composition from its lower end into the annular space formed between the separating material and the outer pipe. The above-mentioned problems are solved by injecting and solidifying the material to form a lightweight concrete insulation material, thereby configuring the main pipe, insulation material, and outer pipe into an integrated structure.

[Function] In the above method for manufacturing an insulated transport pipe, the annular space between the main pipe insulation material and the exterior pipe is filled with lightweight concrete/mortar composition, so no voids remain and the insulation material and exterior The tubes are made into an integral structure through mortar filling.

[Example] Fig. 1 shows an insulated transport pipe manufactured by the method of the present invention, and Fig. 2 shows an example of the manufacturing method.

In Fig. 1, 1 is an insulated transport pipe, 2 is the main pipe of the insulated transport pipe, and its outer peripheral surface is coated with calcium silicate insulation material (JIS A9510) and water-repellent perlite insulation material (
JIS A9512), lightweight concrete insulation material, inorganic insulation material 3 such as foam glass is fixed using high temperature adhesive, wire, etc. Reference numeral 4 denotes an exterior pipe, and a spiral pipe, a steel pipe, a stainless steel pipe, a plastic pipe, or the like is used depending on the purpose of use of the insulated transport pipe l, the installation location, etc. 5 is a sheet-shaped separation material (separator) wrapped around the outer peripheral surface of the inorganic heat insulating material 3, and includes a plastic film,
Polyethylene processed paper (JIS 21514), laminated aluminum foil (JIS Z1520), etc. are used. Reference numeral 6 denotes a lightweight concrete heat insulating material that is compressed and filled in a concentric annular space formed between the outer pipe 4 and the separation member 5. The lightweight concrete heat insulating material 6 is formed by filling the annular space with a mortar composition made of lightweight aggregate, cement, and other additives as necessary, and solidifying the mortar composition.

The mortar compositions used in this invention include foamable and non-foamable ones, and the former includes lightweight aggregate (obsidian foam, plastic foam, etc.), cement and, if necessary, other compounding agents. It contains a foaming agent for mortar as an essential component, and when filled into the annular space, it foams and solidifies, and the foaming pressure fills the annular space in a compressed state. The latter uses compressible lightweight aggregate such as expanded polystyrene beads as an essential component, and in this mortar composition, the lightweight aggregate is compressed by the filling pressure when filling into the annular space. It solidifies as it is, and becomes the lightweight concrete insulation material 6 filled in the annular space in a compressed state.

To manufacture the insulated transport pipe with the above configuration, an inorganic heat insulating material 3 such as a calcium silicate heat insulating material is fixed to the outer peripheral surface of the main pipe 2 using adhesive, wire, etc., and a plastic composite film or the like is fixed to the outer peripheral surface of the main pipe 2. A sheet-like separation material 5 is wrapped around the separator 5, and this is inserted into the exterior tube 4, and these are held in a concentric state and supported at an appropriate angle so that there is a space between the separation material 5 and the exterior tube 4. A plug 7a is provided at the lower end of the annular space to be formed, and a foamable or non-foamable lightweight concrete/mortar composition 6a is poured into the annular space through the plug from the lower end using a known filling device 8 such as a mortar pump. When the air is injected and solidified while replacing the air present in the tube 7, the lightweight concrete insulation material 6 filled in the compressed state shown in FIG. A heat insulating transport pipe l having an integral structure is obtained.

The angle of inclination of the outer tube 4 into which the main tube is inserted concentrically is selected as appropriate depending on the length and inner diameter of the outer tube 4, the inner diameter and thickness (width) of the annular space, the properties of the mortar composition, and the like.

In the above manufacturing method, the annular space 7 formed inside the sheathing tube 4 is inclined so that the annular space 7 is formed from the lower end thereof.
Since the lightweight concrete/mortar composition 6a is injected while displacing the air existing in the annular space, the occurrence of parts that cause performance defects, such as unfilled parts in the annular space 7, is completely eliminated.

In addition, since the insulation layer consisting of the inorganic insulation material 3 and the lightweight concrete insulation material 6 is divided through the separation material 5, thermal stress will not occur even if the insulation transport pipe 1 is subjected to temperature changes during use. This can be alleviated or prevented, and the occurrence of practically harmful phenomena such as destruction of the heat insulating layer can be prevented. and,
The lightweight concrete insulation material 6 filled in the annular space 7 is
Since it is filled in a compressed state due to the foaming action or compression decompression action in the generation process, the heat insulating layer is
Even if the insulating transport pipe 1 is divided by 1, the possibility that the constituent materials of the insulating transport pipe 1 will separate is completely eliminated.

Moreover, since the above method uses a mortar pump or the like to flow the mortar composition 6a into the annular space 7 held concentrically with an inclination, the method does not require expensive equipment. , can be implemented extremely easily and reliably.

In the method, the annular space 7 is held concentrically with an inclination.
In this method, a lightweight concrete/mortar composition is injected and filled from the lower end of the outer pipe, but an exterior pipe that is concentric with the main pipe is stood vertically, and the mortar composition is injected and filled into the annular space from the lower end. However, an insulated transport pipe similar to that described above can be obtained. However, since the transport pipe is very long, approximately Ion in length, in terms of the workability of raising and supporting the outer pipe, as well as the operation of pouring and filling the mortar composition, it is necessary to It is advantageous to support the sheathing tube upright at a low angle of inclination and to fill it with mortar composition from its lower end.

[Effects of the Invention] As described above, the present invention can extremely easily produce an insulated transport pipe with excellent performance such as heat insulation, pressure resistance, and shock resistance.
Moreover, as a method that can be produced economically, it has extremely high utility value in this technical field.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of an insulated transport pipe manufactured by the method of the present invention, and FIG. 2 is an explanatory view showing an example of the manufacturing method. １・・・・・・・・・Insulated transport pipe, ２・・・・・・・・・
・Main pipe, 3...Insulation material, 4...
... Exterior pipe, 5 ... Separation material, 6 ...
・・・・・・insulation material, 7・・・・・・annular space,
8......Filling device, 7a...
・Bung body.

Claims (2)

[Claims] (1) Fix an inorganic heat insulating material to the outer circumferential surface of the main pipe that will become the transport pipe, wrap a separating material around the outer circumferential surface of the insulating material, and then insert the main pipe with the insulating material and separating material into the outer pipe. The lightweight concrete/mortar composition is injected into the annular space formed between the separating material and the outer pipe from its lower end and solidified to create a lightweight structure. A method for manufacturing an insulated transport pipe, characterized by forming a concrete insulation material. (2) The method for manufacturing an insulated transport pipe according to claim 1, wherein a composition in which a foamable composition or compressible lightweight aggregate is blended with the lightweight concrete/mortar composition.