JPS60156868A - Double cylinder heat insulating chimney - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a double-tube heat-retaining chimney comprising an inner cylinder and an outer cylinder made of metal.

BACKGROUND ART Conventionally, as shown in FIG. 1, there is a double-tube heat insulation chimney in which an inner tube 2 made of steel is provided inside an outer tube 1 made of steel or reinforced concrete with an air layer 3 present therein.

In order to absorb the amount of expansion and contraction caused by the temperature difference between the outer cylinder 1 and the inner cylinder 2, expansions 2&, which are made by cutting a steel pipe in half, are welded to the inner cylinder 2 at the required intervals, and each of the expansions 2a is At the bottom, fixing members 4.4 for fixing the inner cylinder 2 to the outer cylinder l are welded to the inner and outer cylinders, respectively, and are fixed to each other.

In this case, the upper and lower parts of the expansion 2a are fixed members 4.
．． 4 is fixed to the outer cylinder, the expansion and contraction of this section is deformed and absorbed by the expansion and contraction as shown by the broken line in FIG. Therefore, the welded portion between the top of the expansion 2& and the inner cylinder 2 is subjected to large repeated stress due to expansion and contraction, and cracks may occur. If smoke continues to pass even after a crack occurs, the leaked exhaust gas will cause the outer cylinder 1, which is a strength member, to
It will corrode the Therefore, extract / 4 in outer cylinder 1
Although it is possible to provide an expansion, it is impossible to expect the strength of the outer cylinder from the expansion due to its structure.

In other words, steel expansions generally only allow a small amount of deformation due to their material properties. Therefore, when the amount of expansion and contraction of the inner cylinder 2 is large, the installation section of the extractor 9 member 2a becomes shorter, which inevitably increases the cost of the inner cylinder construction. For example, if the temperature difference between the inner and outer cylinder steel plates is 50°C, the extension section will be 900°C. Furthermore, if the exhaust gas temperature rises above the design temperature due to changes in operating methods, etc., large-scale modification of the inner cylinder is required.

Further, when a wet type harmful gas removal device is installed in a cleaning plant or the like, the temperature of the exhaust gas decreases from, for example, the designed 300° C. to 100° C., resulting in wasted capital investment.

Moreover, since the heat of the inner cylinder 2 is transferred to the outer cylinder 1 via the fixing member 4, it has a negative effect on the coating of the outer cylinder 1, and the temperature of the exhaust gas is lowered.

The object of the present invention is to provide a double-tube heat-insulating chimney that can solve the problems of the prior art as described above.

The double-tube heat-insulating chimney of the present invention includes an extraction cushion between the top of the outer tube and the upper end of the inner tube made of scrap metal, and an inner tube support that restrains lateral movement relative to the inner surface of the outer tube on the outer circumferential surface of the inner tube. It is characterized in that a member is provided.

An embodiment of the present invention will be described below with reference to the drawings. A plurality of inner cylinder support members 14, 14... are provided on the outer peripheral surface of the steel plate inner cylinder 11.
- are provided in multiple stages in the height direction. This inner cylinder support member 14 is provided with a gap between it and the inner surface of the outer cylinder 1 in consideration of the expansion and contraction of the inner cylinder 12 due to heat, and restricts only the lateral movement of the inner cylinder 12, and The inner cylinder 12 can be expanded and contracted in this direction. An expansion 15 is provided between the upper end of the inner cylinder 12 and the top of the outer cylinder 1. This expansion 15 is, for example, As (Stobellos),
Air can enter and exit by contracting and expanding the air layer 13. If an expansion made of impermeable material is used, a valve is provided that opens and closes depending on the pressure difference between the air layer 13 and the outside world.

In order to protect the extract chamber 15 from rainwater, a cylindrical cover 16 for rain protection is attached to the upper end of the inner tube 12. This cover 16 can also be used when the inner cylinder 12 is extended.
The length is such that it completely covers the extract cushion 15.

Therefore, the amount of expansion and contraction due to the temperature difference between the outer cylinder 11 and the inner cylinder 12 can be absorbed by the extraction tube 15 provided at one location, and the expanding and contracting inner cylinder 12 is supported by the support member 14 in the lateral direction. is supported by the outer cylinder 11, which is a strength member.

Therefore, there is no need to weld a large number of expansions 2a to the inner cylinder 2 as in the conventional case, and there is no need to weld a large number of expansions 2a to the inner cylinder 2.

Since there is no need to weld a large number of fixing members 4, 4 to the outer cylinder, construction costs can be reduced. Also, there is a risk of cracks forming in the inner cylinder. Since there is no padding, the outer cylinder will not be corroded by exhaust gas.

Furthermore, the temperature of the flue gas passing through the same chimney can vary considerably. Furthermore, the influence of the support member 14 on the outer cylinder and exhaust gas temperature can be extremely reduced.

Since the double-tube heat-insulating chimney of the present invention is as described above, it solves the problems of the prior art, significantly reduces costs, and is maintenance-free.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a conventional double-barrel thermal insulation chimney, Fig. 2 is an enlarged view of the part ■ in Fig. 1, Fig. 3 is a longitudinal cross-sectional view showing an embodiment of the chimney of the present invention, and Fig. 4 is a cross-sectional view taken along line IV-IV in FIG. 3; 1)... Outer cylinder, 12... Metal inner cylinder, 13... Air layer, 14゛... Inner cylinder support member, 15... Expansion 7-yon. Applicant's Representative Patent Attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] This is a double-tube heat-insulating chimney consisting of a metal inner cylinder and an outer cylinder, and an extractor is provided between the top of the outer cylinder and the upper end of the metal inner cylinder, and the outer circumferential surface of the inner cylinder is moved laterally relative to the inner surface of the outer cylinder. A double cylinder heat insulation chimney characterized by being provided with an inner cylinder support member that restrains the.