JPS62158995A - Fixed tube plate type heat exchanger - Google Patents

Abstract

PURPOSE:To prevent a tube plate from generating a stress even when the plate is pulled by a method wherein the knuckle part of the end of the tube plate is formed in a curved body and the tube plate is protruded against either one of the chambers of a barrel section and a partitioning section, which has a higher internal pressure. CONSTITUTION:Only the part B of a tube plate 1, to which part a multitude of heat transfer tubes 3 is attached, is a flat surface and a knuckle part A at the end of the tube plate 1 is formed so as to be a curved body, protruding at the center side thereof. In case the internal pressure of a partitioning section 4 is higher than the same of a barrel section 5, the knuckle part A is connected to the plate of the barrel part 5 so as to be protruded against the side of the partitioning section 4. According to this method, a skin stress will never be generated substantially and the connecting angle of the knuckle part A will be changed slightly even when the internal pressure of the partitioning section 4 is increased during operation and the tube plate 1 is pulled. Thus, the load of the tube plate is lightened and the thickness of the same may be thinned. On the other hand, a temperature difference will never be generated and the thermal stress of the tube plate may be mitigated by thinning the thickness of the tube plate.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to improvements in heat exchangers used in chemical plants, steel mills, and the like.

(Prior Art) Conventionally, as the tube plate structure of a fixed tube plate heat exchanger, a flat plate or stepped flat plate was joined at right angles to a body plate.

FIG. 5 is an explanatory diagram of a conventional heat exchanger.

The tube sheet 11 is completely made of a flat plate, and is joined to the body plate 12 at a right angle at a knuckle A at the end of the tube sheet 11.

The upper part of the tube plate 11 is a partition part 14, and the lower part is divided into a body part 15, and a large number of heat transfer tubes 13 are arranged in the body part 15.

During operation of the heat exchanger, pressure is generated in the heat exchanger tubes 13 and the partition section 14, and at the same time, pressure is also generated in the body section 15. In this case, the tube sheet 11 is pulled by the partition side pressure or the body side pressure, and a large membrane stress is generated.

FIG. 6 is also a diagram showing another example of a conventional heat exchanger. The tube sheet 11 is made of a flat plate with steps, and if you exclude the step tube sheet 16 and the straightening plate 17 near the center, the remaining tube sheet 11 is as follows.
As in the case of FIG. 5, it is joined to the body plate 12 at a right angle at the knuckle portion A at its end. The one in the form of is introduced in Japanese Patent Application Laid-Open No. 57-202498.

Also in this case, during operation, pressure is generated in each part, so the tube sheet 11 is pulled by the partition part side pressure or the body part side pressure, and membrane stress is also generated.

(Problems to be Solved by the Invention) According to the conventional technology, as described above, the tube sheet 1 made of a flat plate
1 is joined to the body plate 12 at right angles, the tube plate 11 is pulled by pressure, which causes a large bending stress in the knuckle portion A.

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and provide a heat exchanger that does not generate stress even when the tube sheet is stretched.

(Means for Solving the Problems) In order to achieve this object, the present invention has the following configuration.

That is, in a heat exchanger in which a fixed tube plate is divided into a body and a partition, and a large number of tubes are arranged in the body, the knuckle at the end of the tube plate is a curved body, and the direction of the tube plate is but,
The knuckle and body plate are fully connected to each other so that the convexity of the body and partition is directed toward the high-pressure side of the chamber, so that no stress is generated even when the tube plate is pulled. It is an exchanger.

(Examples and effects) Hereinafter, the present invention will be explained with reference to the drawings.

1 and 2 are explanatory diagrams of a tube sheet structure according to the present invention.

In the tube sheet 1, only the portion B where a large number of heat transfer tubes 3 are attached is flat, and the knuckle portion A at the end is curved. In other words, the entire tube plate 1 is shaped like a trapezoid, with the central portion protruding in a convex shape.

When the internal pressure of the partition part 4 is higher than the internal pressure of the body part 5, a convexity appears on the side of the partition part 4 as shown in FIG. In this case, as shown in FIG. 2, the knuckle portion A and the plate 2 of the body are joined so that the convexity is on the side of the body 5.

In this way, even if the internal pressure of the partition part 4 and the body part 5 increases during operation and the tube plate 1 is pulled due to the partition part side pressure and the body part side pressure, almost no membrane stress is generated. Only the knuckle portion A changes the joint angle slightly.

FIGS. 3 and 4 are explanatory diagrams of other embodiments.

In this case as well, the tube plate 1 has a flat section B where a large number of heat transfer tubes 3 are attached, but the knuckle section at the end is completely rounded.

The fact that the partition part 4 and the body part 5 are made to have a convexity toward the high pressure side is the same as in Figures 1 and 2, so if the pressure increases during operation, , even if the tube sheet 1 is stretched, almost no membrane stress occurs. Only the R shape of the knuckle portion A is slightly deformed.

(Effects of the Invention) According to the present invention, even if the lateral pressure at the partition portion or the lateral pressure at the body increases and the tube sheet is pulled, almost no membrane stress is generated and the entire tube sheet does not stretch. It is economical because the load on the tube sheet is light and the tube sheet can therefore be made thin.

In addition, although there is a difference between the fluid temperature in the partition and the fluid temperature in the body, by making the tube sheet metal thinner, it becomes less likely that a temperature difference will occur in the thickness direction of the tube sheet. Thermal stress can be alleviated.

[Brief explanation of drawings]

Claims (1)

[Claims] In a heat exchanger that is divided into a body and a partition by a fixed tube plate, and has a large number of tubes arranged in the body, the knuckle at the end of the tube plate is curved, and the direction of the tube plate is adjusted to match the body. A fixed tube plate type heat exchanger characterized in that a knuckle part and a body plate are joined so that a convex part is oriented toward a chamber on the high pressure side of the part and partition part.