JPH07305984A - Heat exchanger - Google Patents

Abstract

PURPOSE:To prevent tubes for a heat exchanger from being vibrated in a construction wherein the tubes can be mounted easily by using general-purpose parts, by providing tube seats at positions where buffle plates are mounted in a shell from the external side of the shell, screwing bolts in the shell from the tube seats and forcibly working a force on the buffle plates from the external side of the shell. CONSTITUTION:Buffle plates 4 are coupled to a tube nest 7 so that the buffle plate having a notch on its upper side and the one having a recess on its lower side are successively arranged alternately, and gas flows zigzag through portions among the buffle plates. Vibration-preventing means C such as a tube seat, etc., are mounted on an outer face of a shell 1 at positions reverse to the notch of the respective buffle plates 4. With these arrangement, the tube nest 7 is pressed against the buffle plates 4. Since the directions in which the tube nest 7 is pressed become reverse in sequence, the tube nest 7 among the buffle plates 4 is pressed partly upward and partly downward, thus being fixed securely. According to such a simple construction, the vibration of the tube nest 7 can be prevented without the need for complicated assembly work.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shell and tube heat exchanger for cooling gas compressed by a reciprocating compressor, and more particularly to a structure for preventing tube vibration.

[0002]

[Prior art]

Engineering Book Co., Ltd .: Heat Exchanger Design Handbook (S61
According to the annual edition), generally, shell and tube heat exchangers are roughly divided into shells, water chamber covers and tube nests. First, the shell has a cylindrical shape, and two nozzles are installed at both ends in order to allow gas to pass through the shell, one of which serves as a gas inlet and the other of which serves as a gas outlet. The gas passes through the inlet nozzle, passes through the inside of the shell, and is cooled by heat exchange while being discharged from the outlet nozzle.

The water chamber cover has two nozzles at the top and bottom. Cooling water enters the water chamber cover through the lower nozzle and passes through the insides of a plurality of tubes, returns to the water chamber cover again, and is discharged from the upper nozzle. . Since there is a partition plate inside the water chamber cover, the cooling water before and after heat exchange is not mixed. It is the tube plate that separates the shell and the water chamber cover (cooling water), and at the same time, serves to fix both ends of the tube, which is the passage for the cooling water. The tube is equipped with a plurality of baffle plates via a spacer that serves to keep the intervals constant, and is provided with a notch on the upper side or the lower side to make the gas meander in order to improve heat exchange performance. ing. A tube nest, which is an assembly of a tube plate, a tube, a baffle plate, and a spacer, is described below.

When assembling the tube nest, the baffle plates having the tube penetrating portions are fixed one by one while sandwiching the spacers between the baffle plates so as to keep the baffle plates at a certain interval. In this case, since the number of tubes and the number of baffle plates are large, it is necessary to provide a gap between the tube penetration portion of the baffle plate and the tube.

In this case, the inner surface of the hole at the tube penetrating portion of the baffle plate and the tube may be worn and cracked by being struck by the pressure pulsation of the compressed gas. For example, the baffle plate may be damaged. In that case, the fragments flow into the downstream side of the heat exchanger, causing troubles in other devices.

For example, Japanese Utility Model Application Laid-Open No. 4-12983 discloses a method for suppressing vibration of a tube of a heat exchanger, in which baffle plates are paired to form a two-point support state to improve seismic resistance. .

[0007]

In order to solve the prior art, a method of fixing the baffle plate and the tube by welding can be considered. However, if several tens of tubes are welded to both sides of several baffle plates one by one, the amount of welding work becomes enormous, and there is a problem that the welding work is very difficult because the pitch between the tubes is small. In addition, when the tube is welded, thermal expansion causes a defect in the welded portion, and the thickness of the tube is reduced, resulting in a problem in strength.

The object of the present invention is to reduce the cost by using parts for general purpose products, and to be easily mounted not only on a new heat exchanger but also on a heat exchanger already delivered. To prevent the tube from vibrating.

[0009]

In order to achieve the above object, the present invention provides a pipe seat from the outside of the shell to a position where the baffle plate is attached, from which a bolt is screwed to apply a force to the baffle plate from the outside of the shell. Vibration of the tube was prevented by forcing it to work.

[0010]

The baffle plate is attached to the tube nest so that the notch is formed on the upper side or the lower side in order, and the gas meanders and flows in this portion. Therefore, if a force is applied to the baffle plate from the side opposite to this cutout, when three baffle plates are viewed as a set, both ends of the tube are in one direction by the baffle plates on both sides, and the center of the tube is in the center. Since the baffle plate is pressed from the opposite direction or is pulled and fixed, the tube can be prevented from swinging.

The inner diameter of the shell 1 and the baffle plate 4
A small gap is provided in the outer diameter so that the tube nest 2 can be pulled out at the time of maintenance and assembly.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be described.

FIG. 1 is an assembly view of the heat exchanger. The heat exchanger is composed of a shell 1, a tube nest 2 and a water chamber cover 3. In the tube nest 2, both ends of a tube 7 are fixed by tube plates 2a and 2b, and several baffle plates 4 are arranged between them.

Since the baffle plate 4 has a notch on the upper side or the lower side, the gas that has entered the shell 1 from A meanders through this notch and exits to B. A vibration preventive device C is attached to the outer surface of the shell 1 at a position opposite to the notch of each baffle plate 4.

FIG. 2 shows details of the vibration preventive device C. The vibration preventive device C is composed of a pipe seat 5, a machine bolt 6, and an O-ring 8. The tube seat 5 is attached to the shell 1 by welding and is internally threaded. The machine bolt 6 is screwed into this and the baffle plate 4 is pressed. As a result, the baffle plate 4 presses the tube 7. Since the directions of pressing the tubes are sequentially reversed, the tubes 7 between the baffle plates 4 are fixed because one is pushed upward and the other is pushed downward. In this case, the bolt 6 and the pipe seat 5 have an O-ring 8 so that the gas in the shell 1 does not leak outside.
It is sealed by.

FIG. 3 shows an alternative of FIG. Vibration prevention device C
Is pipe seat 5, stud bolt 9, O-ring 8, nut 10
It is composed by. The tube seat 5 is welded to the shell 1 and is not internally threaded. Since the baffle plate 4 is threaded, the stud bolt 9 is inserted from the pipe seat 5 and screwed into the baffle plate 4. Next, the nut 10 is attached and tightened to the threaded portion of the stud bolt 9 opposite to the side screwed into the baffle plate 4. Thereby, the baffle plate 4 is pulled and the tube 7 is pressed. Since the method of pressing the tubes is sequentially reversed, the tubes 7 between the baffle plates 4 are fixed because one is pressed upward and the other is pressed downward. In this case, the stud bolt 9 and the pipe seat 5 are sealed by an O-ring 8 so that the gas in the shell 1 does not leak outside.

In FIG. 2 and FIG. 3, since the constituent parts are general products, it is possible to take prompt measures when the already-delivered product has a local trouble. Also, in the new heat exchanger, the tube through hole of the baffle plate is designed to be large so that the tube can be easily inserted and work efficiency is improved. Even in such a case, each tube is tightened up with bolts at the end, so that wear and cracks do not occur.

[0018]

According to the present invention, the baffle plate is forcibly pressed from the outside to fix the tube, so that the tube is prevented from vibrating without a complicated assembling work. You can

[Brief description of drawings]

FIG. 1 is an explanatory view of a heat exchanger showing an embodiment of the present invention.

2 is a cross-sectional view of the vibration prevention device in FIG.

3 is a cross-sectional view of the vibration prevention device in FIG.

[Explanation of symbols]

1 ... Shell, 2 ... Tube nest, 2a, 2b ... Tube plate,
3 ... Water chamber cover, 4 ... Baffle plate, 7 ... Tube.

Claims (1)

[Claims] 1. A shell-and-tube heat exchanger for cooling a gas compressed by a reciprocating compressor, wherein a baffle plate provided in a tube nest is provided with a tube fixing means for forcing a force from the outside of the shell. A heat exchanger characterized by that.