JPH066983U - Structure of diaphragm part of pressure vessel - Google Patents

Abstract

(57) [Summary] [Purpose] The function of preventing leakage of internal fluid and confirming the occurrence of internal damage is added to the diaphragm of the pressure vessel. [Structure] An inner diaphragm 6 fitted into a circumferential groove 5 provided in a water chamber body opening 2a and seal-welded on the outer periphery, and having a shape slightly larger than the inner diaphragm 6, the opening 2
An outer diaphragm 7 which is seal-welded to the end surface of a is provided with a through hole 8 penetrating the water chamber body 2 through the gap between the outer diaphragm 7 and the inner diaphragm 6 and opening to the outer peripheral surface of the water chamber body 2, When the water chamber lid 4 is provided outside the outer diaphragm 7 and is bolted to the end face of the water chamber body 2, and when the inner diaphragm 6 is damaged and the fluid in the water chamber 1 leaks, The outer diaphragm 7 prevents direct leakage to the outside, and both inner and outer diaphragms 6, 7
Since the fluid overflowing into the gap flows out to the outside through the through hole 8 from the gap, it can be confirmed that the inner diaphragm 6 is damaged.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure of a diaphragm portion of a pressure vessel such as a heat exchanger of a nuclear power plant.

[0002]

[Prior art]

 A pressure vessel such as a heat exchanger of a nuclear power plant has a water chamber 1 as shown in FIG. 2, and the water chamber 1 has a water chamber body 2 and an outer periphery sealed by an opening 2a of the water chamber body 2. It is formed by a welded diaphragm 3 and a water chamber lid 4 which is bolted to the water chamber body 2 so as to contact the outer surface of the diaphragm 3 so as to press the diaphragm 3 from the outside.

[0003]

[Problems to be solved by the device]

 However, in the structure of the diaphragm portion of the pressure vessel described above, when pressure acts on the inside of the water chamber 1, the water chamber lid 4 has a tendency to bend outward as shown in FIG. 3, and the seal welding of the diaphragm 3 is performed. Since high stress is generated in the portion 3a, the fluid in the water chamber 1 may leak if damage such as a crack occurs near the seal weld 3a.

In view of the above situation, the present invention provides a double-layered diaphragm at the opening of the water chamber body, and provides a through hole communicating with the gap of the double-layered diaphragm, so When the fluid in the water chamber leaks from the diaphragm or its seal weld, the outer diaphragm prevents the fluid from directly leaking to the outside, and the fluid flowing out from the gap through the through hole to the outside. The purpose of the present invention is to provide a structure of the diaphragm part of the pressure vessel that can detect the occurrence of damage such as cracks in the diaphragm part.

[0005]

[Means for Solving the Problems]

 The present invention relates to an inner diaphragm which is fitted in a circumferential groove provided in an opening of a water chamber body and seal-welded on the outer periphery, and an outer diaphragm which has a shape slightly larger than the inner diaphragm and which is seal-welded on the outer periphery to the end face of the opening. A water chamber lid that has a through hole that penetrates the water chamber body from the gap between the outer diaphragm and the inner diaphragm and opens to the outer peripheral surface of the water chamber body, and that abuts on the outer surface of the outer diaphragm. It has a different structure.

[0006]

[Action]

 Therefore, according to the present invention, when damage such as cracks occurs in the diaphragm on the inner side of the water chamber or its seal weld, and the fluid in the water chamber leaks from the damaged part, it is assumed that the fluid directly leaks to the outside. The leak is prevented by the diaphragm, and the leaked fluid overflows into the gap between the inner and outer diaphragms and flows out to the outside through the through hole, so that the leaked fluid can be visually recognized to crack the diaphragm inside the water chamber. It is possible to detect the occurrence of damage such as.

[0007]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing the outline of the structure of the diaphragm portion of the pressure vessel of the present invention. In the figure, the same parts as those in FIG.

In the structure of the diaphragm part of the pressure vessel of the present embodiment, the inner groove formed by providing the peripheral groove 5 of a predetermined depth in the opening 2a of the water chamber body 2 and fitting the peripheral groove 5 into the peripheral groove 5 to seal the outer periphery thereof. An outer diaphragm having a diaphragm 6 and having a diameter slightly larger than that of the inner diaphragm 6 and arranged concentrically close to the outer side of the inner diaphragm 6 and having an outer periphery sealed and welded to the end face of the opening 2a. 7 is provided.

Further, a through hole 8 that penetrates the water chamber body 2 from the end surface of the water chamber body 2 that is in contact with the inner surface of the outer diaphragm 7 and opens to the outer peripheral surface of the water chamber body 2 is formed. Is connected to a leak fluid receiver (not shown) via a pipe 9.

Further, like the conventional pressure vessel shown in FIG. 3, the water chamber lid 4 bolted to the end surface of the water chamber body 2 is in contact with the outer surface of the outer diaphragm 7.

If damage such as cracks occurs in the diaphragm 6 inside the water chamber 1 or the seal welded portion 6a thereof, and the fluid in the water chamber 1 leaks from the damaged portion, the fluid is directly exposed to the outside. The outer diaphragm 7 prevents leakage to the part.

The fluid in the water chamber 1 leaking from the damaged portion overflows into the gap between the inner and outer diaphragms 6, 7 and leaks from the gap between the outer diaphragm 7 and the end face of the water chamber body 2. It is stored in a leak fluid receiver (not shown) through the through hole 8 and the pipe 9.

According to the present embodiment, the outer diaphragm 7 is provided outside the inner diaphragm 6 to form a double structure, and the inner surface of the outer diaphragm 7 and the end surface of the water chamber body 2 are communicated with the gap between the two diaphragms 6, 7. Since a through hole 8 is provided between the through hole 8 and the through hole 8 and a leak fluid receiver is provided through the pipe, it is possible to prevent the fluid in the water chamber 1 from directly leaking to the outside. Moreover, by visually observing the fluid that has flowed out to the leaked fluid receiver, it can be confirmed that damage such as cracks has occurred in the diaphragm 6 inside the water chamber 1.

It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0016]

[Effect of device]

 According to the structure of the diaphragm portion of the pressure vessel of the present invention, various excellent effects as described below can be obtained.

I) Since the diaphragm has a double structure, even if a fluid such as a crack is generated in the diaphragm inside the water chamber and the fluid in the water chamber leaks from the damaged portion, the fluid flows out directly to the outside. Can be prevented.

II) Since the fluid leaking from the damaged portion overflows into the gap of the double structure diaphragm and flows out through the gap to the outside, the inside of the water chamber can be seen by visually observing the flowing out fluid. It can be confirmed that damage such as cracks has occurred in the diaphragm part of.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing the structure of a diaphragm portion of a pressure vessel of the present invention.

FIG. 2 is a cross-sectional view schematically showing an example of a structure of a diaphragm portion of a conventional pressure vessel.

FIG. 3 is a state diagram in the case where internal pressure acts on the diaphragm portion related to FIG. 2;

[Explanation of symbols]

 2 Water chamber body 2a Opening 4 Water chamber lid 5 Circumferential groove 6 Inner diaphragm 7 Outer diaphragm 8 Through hole

Claims (1)

[Scope of utility model registration request] 1. An inner diaphragm which is fitted into a circumferential groove provided in an opening of a water chamber body and seal-welded on the outer periphery, and an outer side which has a shape slightly larger than the inner diaphragm and whose outer periphery is seal-welded on an end face of the opening. A diaphragm having a through hole that penetrates the water chamber body from the gap between the outer diaphragm and the inner diaphragm and opens to the outer peripheral surface of the water chamber body, and has a water chamber lid that abuts the outer surface of the outer diaphragm. The structure of the diaphragm part of the pressure vessel characterized by having.