JPS5820424A - Production of heat-insulated pipe - Google Patents

Abstract

PURPOSE:To obtain a heat-insulated pipe excellent in heat-transmitting property at low production cost, by method wherein an inner pipe and a core are placed in parallel to each other, the two members are covered by a film form member, the assembly is placed in an outer pipe, then both ends of the outer pipe are closed, a raw liquid of a heat insulator is poured into the outer pipe, is foamed and solidified, followed by drawing out the core. CONSTITUTION:The core 6 in a cylindrical foam is placed along the outside peripheral surface of the inner pipe 1 in parallel to the pipe 1, the two members are covered by the film form member 2, and after placing this assembly in the outer pipe 4, both ends of the pipe 4 are plugged up by plugging plates, a raw liquid of the heat insulator 5 is poured into the outer pipe 4, is foamed and solidified. After the heat insulator 5 is foamed and solidified, the plugging plates at the ends of the pipe 4 are removed, and the core 6 is drawn out. Accordingly, since a space in contact with the outside peripheral surface of the inner pipe 1 is produced by using the core, heat-transmitting cement conventionally used can be unnecessitated and a cost-down can be contrived. In addition, the boundary area between the space and the outside peripheral surface of the inner pipe 1 is enlarged by the use of the film form member 2, a heat-insulated pipe having excellent heat-transmitting property can be obtained.

Description

[Detailed description of the invention] The present invention relates to a method of manufacturing a heat insulating tube.

As a type of heat-insulating pipe, a pipe body is fixed to the outer peripheral surface of the inner pipe parallel to the inner pipe, and the inside of the pipe body (steam, hot water, etc.) is fixed to the outer peripheral surface of the inner pipe.

Run a heating fluid such as oil or insert a heating wire.

This heats the fluid to be delivered inside the inner pipe (some are strained). Such insulated pipes are often used for transporting high viscosity fluids or for preventing freezing, but conventional Insulated pipes are used to spot-weld the inner pipe and the pipe body, and to transfer the heat of the heated fluid or heating wire to the transported fluid.

It is manufactured by applying heat transfer cement near the contact area between the inner tube and the tube body. However, this conventional manufacturing method for insulated pipes uses expensive heat transfer cement, resulting in high costs, and the heat transfer properties of the heat transfer cement are insufficient, making it impossible to obtain satisfactory heat transfer properties. There wasn't.

In view of the above-mentioned points, the present invention provides a method for manufacturing an insulated tube that can reduce manufacturing costs and obtain an insulated tube with excellent heat conductivity. I will explain.

In Figures 1 and 2, (1) indicates a steel pipe.

An inner tube made of a synthetic resin tube or the like, (2) is a membrane-like body that covers the outer peripheral surface of the inner tube (1) and forms a substantially cylindrical space (3) in contact with the outer peripheral surface of the inner tube (1). , (4) is a synthetic resin pipe,
It is made of steel pipes, @ pipes, etc., and the radial direction (
This is an outer tube that is divided into outer sections at intervals of this size, and a heat insulating material (5) made of hard urethane foam or the like is filled between the outer tube (4) and the membrane-like body (2). . The membrane-like body (2) is made of paper, paper, polyethylene, etc.
Both ends of the inner tube (1) protrude outward in the axial direction than both ends of the outer tube (4).

When manufacturing an insulated pipe with the above configuration, first the inner pipe (
1) with a cylindrical core (6) attached parallel to the inner tube (1).
) is placed with a membrane-like body (2), and this is placed inside the outer tube (4) between the outer surface of the two membrane-like bodies (2) and the inner peripheral surface of the outer tube (4). Set them so that they are spaced a certain distance apart (Figure 3).

If the membrane body (2) is made of paper (ζ is 1, for example, the inner tube (1) is made of flat paper). ) and the core (6), and fix the overlapping 15 portions of this paper to each other with adhesive.Also, when the membrane (2) is made of a thin shoulder board, it is made of, for example, a flat thin steel plate. This is done by wrapping the inner tube (1) and the core (6), and bending the wheel-like parts of this thin steel plate and engaging them with each other. For example, if the inner tube (1) and the core (6) are inserted into the tube, the inner tube (11) covered with the membrane (2) is
In order to fix the core (6) with the specified IJ in the outer f4' (4), it must be supported by supports (not shown) at both ends of the inner tube (1), or by a membrane-like body (2). ) Attach a suitable spacer to the outer surface of the outer tube (4).Next, close both ends of the outer tube (4) with ice plates (not shown), and insert the insulation material (5) into the outer tube (4). liquid to l-
One person foams and solidifies it (Figure 4). At this time, the membrane (2) is slightly deformed as shown in FIG. 4 due to the foaming pressure of the heat insulating material (5). After the heat insulating material (5) is foamed and solidified, the closed substrates at both ends of the outer tube are removed and the core (6) is extracted (FIG. 5). At this time, there is a membrane (2) between the core (6) and the heat insulating material (5).
) is present on the outer circumferential surface of the core (6 insulators).
) is not attached, the core (6) can be easily pulled out, and the heat insulating material (5) will not be damaged when the core (6) is pulled out. This process completes the insulated pipe.If the membrane is made of, for example, a 511N thin steel plate or 8ff thick paper, the membrane will not deform due to the foaming pressure of the insulation material. .

1 In this way, manufacturing costs can be reduced because expensive heat transfer cement is not used as in the past.In addition, the insulated pipe' manufactured in this way has a large space (3) with a total area of 1) (1)
) It is in contact with the circumferential surface, so as shown in Figure 6 (
Pipe body (7) for flowing heating fluid into this space (3) ib
Or when a heating wire is inserted, the heat of the body or the body is efficiently and smoothly (limb feeding fluid within January).
This is transmitted 3, because the elbow position (7) moves freely within the space (3).

At the time of connection, -L (when connecting this 1θr heat function).

This makes it easier to connect the tube bodies (h). Note that the 'l-f body (7) is the space (
You can insert it in 3), or you can insert it in space (3) by
You may insert it into

The above embodiment (1) describes an example in which the core (6) is attached to the outer peripheral surface of the inner part (1) and the whole is covered with the film-like body (2). Body (2) is space (3)
The area of contact between the inner tube ( ) and the surrounding surface is wide and the core (
6) Since it is a t-hole that makes it easy to remove, it is not necessarily inside! It is not necessary to cover the entirety of (1) and the core (6). For example, as in the seventh factor, a membrane-like body (8) having a width narrower than the membrane-like body (2) in the jar of the above embodiment is used. This film-like body (8) covers the outer peripheral surface of the core (6).
) may be fixed (rubbed) to the outer peripheral surface of the inner tube (1).

Further, in addition to the above embodiment, an example using a single cylindrical core (6) (although the explanation has been elaborated, it goes without saying that the core (6) may be cylindrical. It may be an elliptical or polygonal column or cylinder.

As explained above (9) According to the method of manufacturing a heat insulating pipe according to the present invention, a space in contact with the outer peripheral surface of the inner pipe is created by the core, so there is no need to use heat transfer cement as in the past. In addition, since the contact area between the space and the outer circumferential surface of the inner tube is made sufficiently large by the membrane, it is possible to reduce the heat of the heating fluid or the heating wire through the heat transfer cement as in the past. It is possible to obtain an insulated tube with superior heat transfer efficiency compared to a tube in which heat is transferred to the fluid being fed.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a sectional view along the radial direction of a completed insulated pipe, FIG. 2 is a sectional view along the axial direction of the same insulated pipe, and FIGS. FIG. 6 is a cross-sectional view for explaining the manufacturing process, FIG. 6 is a cross-sectional view of the tubular body inserted into the space, and FIG. 7 is a cross-sectional view for explaining a modified example of the membrane-like body. (1)...inner tube 12) (81... membranous body, (4)...
-Geku, (5)...Insulation, (6)...Nakako agent Yoshihiro Morimoto-153=

Claims (1)

[Scope of Claims] (1) The outer circumference 1fIiii of the inner tube is parallel to the inner tube. After inserting these into the outer tube, both ends of the outer tube are closed, and the stock solution of the heat insulating material is injected into the outer tube to foam and solidify. A method for manufacturing a heat insulating pipe, characterized in that the core is then removed.