JPS6128337Y2 - - Google Patents

Description

[Detailed description of the invention] When incorporating a tubular electric heating element in an electric heater etc. into the heater, a tube plate such as a steady rest is provided in the middle of the tubular heating element to support the tubular heating element. There is a need. In this case, since the heating element has a structure that penetrates the tube sheet, the heating element and the tube sheet must be electrically insulated.

Conventional devices for insulating the heating element and the tube plate are shown in FIGS. 1 and 2.

Figure 1 shows a hollow bolt-shaped insulator a and a tube plate b.
The insulators a and c are attached to the tube plate b by fitting the nut-shaped insulator c onto the insulator a, and the heating element d is passed through the insulator a. There is.

FIG. 2 shows a hollow insulator e having a flange portion is fitted into a tube plate b, and the flange portion of the insulator is inserted between the tube plate b and an insulator mounting sleeve f to attach the insulator. A heating element d is shown passing through the body e.

However, the above method has the following problems.

In the case shown in Figure 1, (i) the insulator requires threading, so the material of the insulator is limited to those that can be machined, and (ii) the shape is complex, which increases the cost of machining. (iii) If an external force is applied to the insulator due to deformation of the heating element, the insulator will be damaged from the threaded portion of the insulator. Furthermore, in the case shown in FIG. 2, (i) the shape is complicated and processing costs increase; (ii) when external force is applied to the insulator due to deformation of the heating element, the external force is concentrated on the flange portion and the insulator is damaged.

The present invention was developed to solve this problem, and consists of a ring-shaped insulator with a hole in the center for passing through the heating element, which is held between a pair of insulator mounting rings, and the insulator mounting ring is It is characterized in that the heating element is fixed to a tube sheet that supports the heating element.

An embodiment of the present invention will be described below with reference to FIG.

A hole 2 for passing through the heating element is bored in the tube sheet 1, and a ring-shaped insulator 3 is positioned in the center of the hole.
The ring-shaped insulator 3 is inserted and fixed by insulator attachment rings 4 and 5 that are fixed to the insulator. The insulator attachment rings 4 and 5 have an outer diameter that can fit into the hole 2 and a recess into which the ring-shaped insulator 3 can be fitted,
As shown in the figure, the ring-shaped insulator 3 can be positioned in both the radial direction and the thickness direction.
By passing the heating element 6 through the hollow part of the ring-shaped insulator 3, the heating element 6 is supported by the tube plate 1 via the ring-shaped insulator 3 and the insulator mounting rings 4 and 5.

With the above configuration, the heating element 6 is completely insulated from the tube plate 1, and the shape of the insulator 3 is simple, so even if an external force is applied to the insulator 3 due to deformation of the heating element 6, it will not be damaged. .

FIG. 4 shows another embodiment in which the insulator mounting rings 7, 8 have annular protrusions 9, 10 on one side thereof.
The outer diameter of the protrusions 9 and 10 is formed to match the inner diameter of the hole in the tube plate 1, and the inner diameter of the protrusions 9 and 10 is formed to match the outer diameter of the ring-shaped insulator 3. Therefore, in this embodiment as well, the simple ring-shaped insulator 3 can be easily positioned and fixed at the center of the hole.

It goes without saying that the shape of the insulator mounting ring is not limited to the shape of the above embodiment, and that various changes can be made.

As explained above, since the present invention has a structure in which the insulator is held between rings, the shape of the insulator to be held can be simplified, insulators that cannot be machined can be used, and the position of the insulator can be easily positioned. The shape of the insulator mounting ring is also simple, and excellent effects can be exhibited.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing a conventional heating element insulation part, FIG. 3 is a cross-sectional view showing an embodiment of the present invention, and FIG. 4 is a cross-sectional view showing another embodiment of the present invention. . 1 is a tube plate, 2 is a hole, 3 is a ring-shaped insulator, 4,
5, 7, 8 are insulator mounting rings, 6 is a heating element,
9 and 10 indicate convex portions.

Claims (1)

[Scope of utility model registration request] A ring-shaped insulator having a hole in the center for passing through the heating element is held between a pair of insulator mounting rings, and the insulator mounting ring is fixed to a tube plate that supports the heating element. Insulation structure of through-type electric heating element.