JPH0270331A - Uniform tube expanding device - Google Patents

Abstract

PURPOSE:To improve the efficiency by forming a tube expanding medium in combination with plural media different in mechanical properties to expand the tube by different expanding rates. CONSTITUTION:In a tube end structure having a range 11 requiring air-tightness and a range 12 requiring adhesion, sealing members 7, 7 are provided respectively on the side of the head 6 of a pressure rod 5 and the side of a backup spring 4. Between the sealing members, a soft elastic sleeve 8 is built in a part having grooves 10 on the tube plate 1 and in a part of a range 11 requiring air- tightness, while a hard sleeve 9 is built in the part 12 requiring another adhesion. When a pressure rod 5 is pulled in the direction of an arrow F, tube material 2 is expanded outward by the expanding pressure to the radial direction. A large tube expanding rate is obtained in the part of a soft elastic sleeve 8 while a small pipe expanding rate is obtained in the part of a hard elastic sleeve 9. By this method, the reduction of the number of tube expansions improves efficiency and can dissolve the residual stress of the pipe end part.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to the uniform expansion of tube ends of heat exchangers, etc., and is particularly applicable to thick tube plates to ensure airtightness and adhesion. The present invention relates to a uniform expansion tube expansion device suitable for.

[Conventional technology]

In the conventional uniform expansion method, the end of the tube 2 is inserted into a hole drilled in the tube plate 1, as shown in FIG.
A sleeve-shaped tube expansion medium 3 made of an elastic material such as rubber is inserted into the end of the tube expansion medium 3, and its outer end is pressed by a bubble ring 4. By bringing the head 6 into contact with the lower end of the pipe expansion medium 3 and pulling the pressure rod 5 in the direction of arrow F, the head 6 pressurizes and compresses the pipe expansion medium 3, thereby radially The pressure of the expansion causes the tube material 2 to expand outward, and the tube sheet l
It is designed to be crimped onto the inner circumferential surface of the hole. 7.
7' indicates a sealing member. Note that related devices of this type include, for example, Japanese Patent Publication No. 53-12464.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into account the combination of tube expansion degrees, and since only one type of elastic sleeve is used, only the same degree of tube expansion can be obtained in the entire tube end range where tube expansion is performed at the same time, and different degrees of tube expansion can be obtained. There was a problem in that if you wanted to obtain the same, you would have to do it in several parts.

SUMMARY OF THE INVENTION An object of the present invention is to provide a uniform expansion device that can simultaneously obtain different degrees of tube expansion in one tube expansion operation.

[Means to solve the problem]

The above object is achieved by combining rubbers and the like with different mechanical properties as the tube expansion medium.

That is, this can be achieved by using soft rubber as the tube expansion medium for areas where airtightness is required, and by using hard rubber as the tube expansion medium for areas where only adhesion is required.

[For production]

Even under the same pressure rod tensile force, the mechanical properties of the respective elastic sleeves are different, so the pressures at which they expand in the radial direction are also different. As a result, the forces that cause the tube material to expand outward also differ, resulting in airtightness and adhesion. A structure that can be used in combination with IS properties can be constructed.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. As shown in the figure, in the tube end structure each having a region 11 requiring airtightness and a region 12 requiring only adhesion, parts common to those in FIG. 2 are given the same reference numerals and explained as follows.
Seal members 7 and 7' are respectively placed on the head 6 side of the pressure rod 5 and on the Babkuadzupling 4 side, and between them, there is a group 10 on the tube plate 1, and a soft seal is placed in the area 11 that requires airtightness. In addition to the elastic sleeve 8, a hard elastic sleeve 9 is provided in other areas where only adhesion is required. Pressure rod 5
When pulled in the direction of arrow F, the tube expansion media 8 and 9 expand the tube material 2 outward due to the radial expansion pressure due to the compressive action applied to the entire tube material, and press it against the inner peripheral surface of the hole in the tube plate 1. let In this case, a large degree of tube expansion can be obtained in the soft elastic sleeve 80 portion, and a small degree of tube expansion can be obtained in the hard elastic sleeve 9 portion, thereby achieving tube expansion that satisfies each requirement at the same time.

According to this embodiment, there is an effect that different degrees of pipe expansion can be obtained for arbitrary ranges by simultaneous pipe expansion. Therefore, in addition to improving efficiency by reducing the number of tube expansions, it is also effective in eliminating residual stress at the tube ends.

〔Effect of the invention〕

According to the present invention, there is an effect that different degrees of pipe expansion can be obtained in arbitrary ranges by simultaneous pipe expansion.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a tube expanding device that combines two types of tube expanding media according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a tube expanding device that uses a conventional tube expanding medium. ! ...Tube sheet, 2...Pipe material, 3...
...Pipe expansion medium, 5...Pressure rod, 8...
...Soft elastic sleeve, 9...Hard elastic sleeve, 10...Group, 11...
・Area that requires airtightness, C... Figure 1 that requires adhesion

Claims (1)

[Claims] 1. A tube expansion medium is charged into the tube expansion processing section of the tube material to be inserted into the hole in the tube sheet, and the tube expansion medium is pressurized in the tube axis direction to expand the tube material, and the pipe material is expanded into the tube sheet. In the pipe expansion device for fixing the pipe, the pipe expansion medium is formed by a combination of a plurality of media having different mechanical properties, and is configured to obtain different degrees of pipe expansion within an arbitrary range. Device. 2. In claim 1, the plurality of media are formed of a soft elastic sleeve and a hard elastic sleeve,
A uniform extrusion and tube expansion device characterized by being configured to obtain airtightness and adhesion within an arbitrary range depending on each medium.