JP2003294717A - Seismic isolation damper and inspection method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple and precise inspection method of a seismic isola tion damper that can inspect the joined state of a part of a lead column body and a flange simply and highly reliably by a nondestructive inspection and the seismic isolation damper which is inspected by the method. <P>SOLUTION: When an ultrasonic wave is incident from a flange side on a certain inspection area of a joined part of a lead column body and the flange, if a reflected echo from the joint part is greater than a predetermined threshold, it is judged that a joint defect is detected in the inspection area. In addition, the joined state of the lead column body and the flange of the whole damper is judged from a ratio of inspection areas where joining defects exist to the total areas to be inspected of the presence of joining defects using a method in which when an ultrasonic wave is incident from a flange side on a certain inspection area of a joined part of the lead column body and the flange, if a reflected echo from the joined part is greater than a predetermined threshold, a joining defect is detected in the inspection area. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation damper for suppressing the shaking of a structure due to an earthquake or the like to protect the structure and an inspection method thereof.

[0002]

2. Description of the Related Art In recent years,
Various seismic isolation dampers are used for the purpose of protecting the structure by suppressing the shaking of the structure due to an earthquake or the like. Figure 4
FIG. 6 is a diagram showing an example of these seismic isolation dampers. This seismic isolation damper has a structure in which flanges 2 are joined to both end surfaces of a lead column body 1 provided with a curved portion 1a that curves along one plane.

In this seismic isolation damper, the bending portion 1
In a, the central portion is curved by a predetermined amount, and the curved portion is curved in opposite directions from both ends to reach both ends. The lead column 1 has a so-called taper shape in which the diameter gradually increases from the curved portion 1a to both end portions, and both end surfaces are parallel to each other and face each other. .

The flanges 2 attached to both end surfaces of the lead column body 1 are made of a steel material (steel plate) such as stainless steel and have a surface larger than both end surfaces of the lead column body 1. . In addition, holes 4a for fixing to the structure and the foundation of the structure with bolts are provided at the four corners of the flange 2.

This seismic isolation damper constructed as described above is usually connected between the building and the foundation via the flanges 2 at both ends in the seismic isolation structure, and the lead column body 1 is protected against vibration. By softly plastically deforming, it absorbs vibration energy, imparts damping performance to the base isolation structure, and suppresses excessive relative displacement between the building and the foundation.

In order for the above-mentioned seismic isolation damper to absorb vibration energy and impart damping performance to the seismic isolation structure, and to surely fulfill the action of suppressing excessive relative displacement between the building and the foundation, It is an essential requirement that the structure 2 and the flange 2 fixed to the foundation of the structure and the lead column 1 that absorbs vibration energy are securely joined.

By the way, the seismic isolation damper described above is, for example,
(1) A step of applying a homogen welding material to the joint surface of the flange 2 with the lead column body 1 and smoothing the surface to which the homogen welding material is applied, (2) casting the molten lead with a die While molding the lead column body 1 having a predetermined shape, the lead column body 1
Machining both end faces of (3) Molded lead column 1
(4) Forming lead on the both ends of the flange by joining the homogen-welding surface of the flange, heating the joint (joint surface) A, and homogen-welding the outer periphery It is manufactured through a process of machining both ends of the column 1 to finish it to a predetermined accuracy and size. As described above, the lead column 1 and the flange 2 are joined by a method using a so-called lead homogen. However, the joining method using lead homogen requires sufficient experience and a high degree of skill, and is inexperienced. When the worker is engaged in manufacturing, the joint strength between the lead column 1 and the flange 2 may be insufficient, and the prescribed seismic isolation effect may not be obtained, so that the reliability is not always sufficient. There is a problem that is not.

[0008] Further, to check the joining state of the lead column 1 and the flange 2 by a method of nondestructive inspection is (1) joining of steel materials such as stainless steel and foreign materials such as lead or lead alloy. It is not easy because of its special condition, (2) Lead or lead alloy is used as the main material, and it is not suitable for X-ray photography.
In reality, it is extremely difficult to reliably judge the quality of a seismic isolation damper that is a product.

The present invention has been made in view of the above circumstances, and a method for inspecting a seismic isolation damper capable of surely inspecting the joining state of a lead column and a flange by a non-destructive inspection method and the inspection. It is intended to provide a highly reliable seismic isolation damper that has been inspected by the method.

[0010]

In order to achieve the above object, the seismic isolation damper inspection method of the present invention (Claim 1) comprises:
Judgment of the joint state of the lead column body and the flange of the seismic isolation damper in which flanges made of steel are joined to both end surfaces of the column body made of lead or lead alloy (hereinafter referred to as "lead column body") An inspection method for doing so, in which a predetermined inspection area of the joint between the lead column and the flange is irradiated with ultrasonic waves from the flange side, the reflected echo from the joint is detected, and the size of the reflected echo is It is characterized in that it is judged that there is a bonding defect in the inspection region when it is larger than a predetermined threshold value.

An ultrasonic wave is incident from the flange side into a predetermined inspection area of the joint between the lead column and the flange, a reflected echo from the joint is detected, and the magnitude of the reflected echo exceeds a predetermined threshold value. If it is large, it is possible to easily and surely detect the presence or absence of a bonding defect by determining that the inspection region has a bonding defect, and to perform a reliable judgment of the quality of the bonding state.

That is, when the lead column and the flange are securely joined, ultrasonic waves are easily transmitted from the flange to the lead column at the joining portion, and the reflection echo from the joining portion becomes small. When the body and the flange are not securely joined (for example, when a gap exists in the joint), the reflection echo from the joint becomes large depending on the size of the gap (defect). Therefore, for example, the relationship between the size of the reflection echo and the performance of the seismic isolation damper, which is a product, is checked in advance, and a predetermined threshold value is set. When the reflection echo becomes larger than the threshold value, the bonding state is poor. By determining (there is a bonding defect), it is possible to easily and surely detect the presence or absence of a bonding defect, and to judge whether or not the bonding state is highly reliable.

The seismic isolation damper inspection method of the present invention (Claim 2) is such that a flange made of steel is joined to both end faces of a column made of lead or lead alloy (hereinafter referred to as "lead column"). An inspection method for inspecting a joint state between the lead column body and the flange of a seismic isolation damper, which comprises applying an ultrasonic wave from a flange side to a predetermined inspection region of a joint portion between the lead column body and the flange. Then, by detecting the reflection echo from the joint, by the method of determining the presence or absence of the joint defect in the inspection region from the size of the reflection echo, the joint defect of the plurality of inspection regions of the joint portion of the lead column and the flange. Judging the presence / absence of the lead column body and the flange as a seismic isolation damper as a whole based on the ratio of the inspection area where the joining defect is recognized to all the inspection areas where the presence or absence of the joining defect is judged. Featuring That.

A method of injecting ultrasonic waves from the flange side into a predetermined inspection region of the joint between the lead column and the flange and determining the presence or absence of a joint defect in the inspection region based on the size of the reflected echo is used. The presence or absence of joint defects is determined for multiple inspection areas of the joint part of the flange and the flange, and the ratio of the inspection area in which joint defects are recognized to all the inspection areas where the presence or absence of joint defects is judged By judging the quality of the joint between the lead column and the flange,
Further, it becomes possible to reliably judge the quality of the joint state of the lead column body and the flange of the seismic isolation damper as a whole, and it is possible to effectively present the present invention.

The seismic isolation damper inspection method of the present invention (Claim 3) is such that a flange made of steel is joined to both end faces of a columnar body made of lead or lead alloy (hereinafter referred to as "lead columnar body"). An inspection method for inspecting a joint state of the lead column body and the flange of a seismic isolation damper, which comprises: (a) partitioning the entire joint portion into an inspection area having a predetermined area and performing each inspection. The presence or absence of a bonding defect is determined for the area, and (b)
The feature is that the quality of the joint state of the lead column body and the flange of the seismic isolation damper as a whole is determined from the ratio of the total area of the inspection region where the joint defect is recognized to the total area of the joint portion.

The entire area of the joint is divided into inspection areas having a predetermined area, the presence or absence of a junction defect is determined for each inspection area, and the total area of the inspection areas in which the joint defect is recognized is the total area of the joint. By determining the quality of the joint between the lead column and the flange as the seismic isolation damper as a whole, it is possible to more reliably determine the quality of the joint between the lead column and the flange as the seismic isolation damper as a whole. Therefore, the present invention can be effectively realized.

The seismic isolation damper inspection method according to claim 4 is characterized in that the flanges are joined to both end surfaces of the lead column body by a lead homogen or soldering method.

When the flanges are joined to both end faces of the lead column body by a method using lead homogen or soldering, the joint state of the lead column body and the flange tends to be a problem. By applying the present invention, it is possible to reliably determine the quality of the joint state between the lead column body and the flange, and it is possible to provide a highly reliable seismic isolation damper.

Further, the seismic isolation damper inspection method according to a fifth aspect is characterized in that the lead columnar body has a curved portion which is curved along one plane.

As a seismic isolation damper using a lead column, it is known that a large seismic isolation effect can be obtained when the lead column has a curved portion that curves along one plane. However, even when the lead column body has such a curved portion, by applying the present invention, it becomes possible to reliably determine the quality of the joined state of the lead column body and the flange, It is possible to provide a highly reliable seismic isolation damper with a large seismic effect.

According to a sixth aspect of the present invention, the seismic isolation damper inspecting method detects a reflection echo from the joint portion, and determines the presence or absence of a joint defect in the inspection area based on the size of the reflection echo. The feature is that when the size of the wave reflection echo is 62% or more of the incident ultrasonic waves, it is determined that the inspection region has a bonding defect.

In detecting the reflection echo from the junction and determining the presence or absence of a junction defect in the inspection area from the size of the reflection echo, the size of the first wave reflection echo is 62% of the incident ultrasonic wave. By determining that there is a joint defect in the above cases, it is possible to reliably determine the quality of the joint state between the lead column body and the flange, and it is possible to further effectively realize the present invention. It should be noted that when the size of the first wave reflection echo is 62% or more of the incident ultrasonic wave, it is determined that there is a bonding defect because the size of the first wave reflection echo is the incident ultrasonic wave. Of 6
This is because when the content is 2% or more, a joint defect is recognized with a probability of 100% in the destructive inspection.

Further, the seismic isolation damper of the present invention (claim 7) is inspected by the seismic isolation damper inspection method according to any one of claims 1 to 6, and it is confirmed that the lead column and the flange are joined well. It is characterized in that it is determined to be.

The seismic isolation damper of the present invention is inspected by the seismic isolation damper inspection method according to any one of claims 1 to 6, and is determined to be in a good joint state between the lead column and the flange. According to the inspection method of claims 1 to 6, it is possible to reliably determine the quality of the joining state of the lead column body and the flange, so that it is possible to provide a seismic isolation damper with high reliability. Become.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The features of the present invention will be described below in more detail with reference to the embodiments of the present invention.

[Embodiment 1] (1) Test Sample In this Embodiment 1, as a test sample, as shown in FIG. 1, lead homogenates were formed on both upper and lower surfaces of a lead cylinder (lead block) 11 corresponding to a lead column. By the method, a cylindrical joint structure (corresponding to a seismic isolation damper) having a structure in which the stainless steel material 12 corresponding to the flange was joined was produced. The conditions such as the size of the test sample are as follows. (a) Lead cylinder (lead block) 11 thickness t1: 100 mm (b) Stainless steel material 12 thickness t2: 30 mm (c) Joint structure dimensions Thickness T: 160 mm Diameter D: 200 mm

(2) Inspection of Joined State From the stainless steel material 12 side, ultrasonic waves are incident on a predetermined inspection area of the joint (joint surface) B of the lead cylinder 11 and the stainless steel material 12, and a reflection echo is generated by the probe. The size was examined, and based on the size of the reflection echo, it was determined whether or not the joined state of the lead cylinder 11 and the stainless steel material 12 constituting the joined structure (seismic isolation damper) was good.

FIG. 2 is a diagram showing the relationship between the ultrasonic wave propagation time and the size of the reflected echo when the size of the reflected echo is examined by the probe. As shown in FIG. 2, the first wave reflection echo by the first reflection, the second wave reflection echo by the second reflection, and the third wave reflection echo by the third reflection decrease in size in this order. I understand. In FIG. 2, the first-wave reflected echo, the second-wave reflected echo, and the third-wave reflected echo are detected, but normally, it is possible to detect the joining state from only the first-wave reflected echo. Therefore, also in the first embodiment, the bonding state was examined only from the first wave reflection echo.

In the first embodiment, (a) an inspection (non-destructive inspection) for checking the bonding state by injecting the above-mentioned ultrasonic wave and measuring the size of the first wave reflection echo,
(b) Inspection for examining the joint state by cutting the joint structure and exposing the joint surface of the lead cylinder 11 and the stainless steel material 12, and for examining the shear strength in the parallel direction of the joint surface (destruction inspection) Then, the reliability of the inspection of the bonding state by the size of the reflection echo was examined. The results are shown in Table 1.

[0030]

[Table 1]

As a result, as shown in Table 1, in the first embodiment, in the inspection of (a), the inspection area in which the magnitude of the first wave reflection echo is 62% or more of the incident ultrasonic wave In the destructive inspection of (b) above, a bonding defect was recognized with a probability of 100%. On the other hand, in the inspection area in which the size of the first wave reflection echo is 30% or less of the incident ultrasonic waves, no junction defect was observed in the destructive inspection in (b) above.

From the above results, the magnitude of the first wave reflection echo is 6 for the incident ultrasonic wave in the predetermined inspection area.
With respect to the inspection area of 2% or more, it is possible to judge that there is a 100% probability that the bonding defect exists, and the size of the first wave reflection echo is 30% or less of the incident ultrasonic wave. It can be seen that it is possible to determine that no junction defect exists in the region. Note that FIG. 3 is a diagram schematically showing a state in which the bonding defect 13 exists in a part of the bonding portion B of the bonded structure.

[Second Embodiment] In the second embodiment, as shown in FIG.
As shown in FIG. 1, the lead column body 1 including the bending portion 1 a, the bending portion 1
A seismic isolation damper (product) having a structure including a structure 2 and a flange 2 having a hole 2a for bolting to the structure and a foundation of the structure, which is joined to both ends of the structure by the method of the present invention, The joint state of the joint portion (joint surface) A between the lead column body 1 and the flange 2 was examined. The detailed structure of the seismic isolation damper shown in FIG. 4 has already been described in the section of the conventional art, and therefore the description thereof is omitted here to avoid duplication.

Regarding this seismic isolation damper, the lead column 1
In examining the joining state of the flange 2 and the flange 2, (a) the entire area of the joining portion A is divided into inspection areas having a predetermined area, and an ultrasonic wave is incident on each of the divided inspection areas from the flange 2 side. Then, the size of the first-wave reflected echo is examined with a probe, and the size of the first-wave reflected echo is more than that, with 62% of the incident ultrasonic waves as the threshold value. It is judged that there is a joint defect in (3), and the quality of the joint state between the lead column body 1 and the flange 2 is judged. The quality of the joint between the lead column 1 and the flange 2 of the damper as a whole is determined, and (c) the seismic isolation damper is cut to obtain the lead column 1.
Then, an inspection for checking the bonding state by exposing the bonding surface of the flange 2 and a test for checking the shear strength in the direction parallel to the bonding surface (destructive inspection) were performed.

As a result, also in the case of the second embodiment, the inspection area in which the size of the first wave reflection echo is 62% or more of the incident ultrasonic wave is 100% in the destructive inspection of (c). A joint defect was recognized with a probability. On the other hand, in the inspection area in which the size of the first-wave reflected echo is 30% or less of the incident ultrasonic waves, no junction defect was found in the destructive inspection in (c) above.

From the above results, even in the case of an actual product, there is a 100% probability that the size of the first wave reflection echo is 62% or more of the incident ultrasonic wave in the predetermined inspection region. It may be judged that a bonding defect exists, and it may be judged that a bonding defect does not exist in an inspection region in which the size of the first wave reflection echo is 30% or less of the incident ultrasonic wave. Was confirmed. In the first and second embodiments, the size of the first wave reflection echo is checked, and the presence or absence of a bonding defect in the inspection area is determined using 62% of the incident ultrasonic waves as a threshold value. However, the threshold value is not necessarily limited to 62%, and it is possible to set an appropriate threshold value in consideration of conditions such as the type, size and shape of the constituent material of the lead column and the flange. desirable.

The present invention is not limited to the above-described first and second embodiments in other respects as well, and the specific shapes of the lead column and the flange, the frequency of the incident ultrasonic wave, and the lead column. Various applications and modifications can be made within the scope of the invention with respect to a method of partitioning the inspection area of the joint portion of the flange and the like.

[0038]

As described above, the seismic isolation damper inspection method according to the present invention (Claim 1) applies ultrasonic waves from the flange side to a predetermined inspection region of the joint between the lead column and the flange, Since the reflected echo from the joint is detected and if the magnitude of the reflected echo is larger than a predetermined threshold value, it is determined that there is a joint defect in the inspection area, it is easy to determine the presence or absence of the joint defect. In addition, it is possible to reliably detect and make a reliable quality decision.

That is, the relationship between the size of the reflection echo and the performance of the seismic isolation damper, which is a product, is checked in advance, and a predetermined threshold value is set. If the reflection echo becomes larger than the threshold value, the joining state is not good. By determining that there is a bonding defect (there is a bonding defect), it is possible to easily and surely detect the presence or absence of a bonding defect, and perform a highly reliable judgment of the bonding state.

The seismic isolation damper inspection method of the present invention (claim 2) is such that ultrasonic waves are incident from the flange side into a predetermined inspection region of the joint between the lead column and the flange, and the magnitude of the reflection echo is increased. From the method of determining the presence or absence of a bonding defect in the inspection region, to determine the presence or absence of bonding defects for a plurality of inspection regions of the joint portion of the lead column and the flange, for all the inspection regions that have been determined the presence or absence of bonding defects, The quality of the joint between the lead column and the flange of the seismic isolation damper as a whole is determined based on the proportion of the inspection area where a joint defect was found. It becomes possible to judge the quality of the joined state of the flanges, and the present invention can be effectively realized.

Further, the seismic isolation damper inspection method of the present invention (claim 3) divides the entire joint portion into inspection regions having a predetermined area, and judges the presence or absence of a joint defect in each inspection region, The quality of the joint between the lead column body and the flange of the seismic isolation damper as a whole is determined from the ratio of the total area of the inspection area where the joint defect is recognized to the total area of the joint, so it is more reliable. It becomes possible to judge the quality of the joining state of the lead column body and the flange of the seismic isolation damper as a whole, and it is possible to effectively present the present invention.

When the flanges are joined to both end faces of the lead column body by a method such as lead homogenization or soldering, the joint state of the lead column body and the flange tends to be a problem. In this case, by applying the present invention as described in claim 4, it is possible to reliably judge the quality of the joined state of the lead column body and the flange, which is particularly significant.

As a seismic isolation damper using a lead column, it is known that a large seismic isolation effect can be obtained when the lead column has a curved portion that curves along one plane. However, even when the lead column body has such a curved portion, by applying the invention of the present application as in claim 5, it is possible to ensure the quality of the joined state of the lead column body and the flange. Can be determined.

According to the seismic isolation damper inspection method of claim 6, in detecting the reflection echo from the joint portion and judging the presence or absence of the joint defect in the inspection region from the size of the reflection echo, When it is determined that there is a bonding defect when the size of the one-wave reflected echo is 62% or more of the incident ultrasonic waves, it is possible to reliably judge the quality of the bonding state between the lead column and the flange. Therefore, the present invention can be further effectively realized.

Further, the seismic isolation damper of the present invention (Claim 7) is inspected by the seismic isolation damper inspection method according to any one of Claims 1 to 6, and it is confirmed that the lead column body and the flange are joined well. According to the inspection method of claims 1 to 6, it is possible to reliably determine the quality of the joining state of the lead column body and the flange, and thus it is possible to reliably provide high reliability. It becomes possible to provide seismic isolation dampers.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a test sample (bonding structure) used in a first embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between the ultrasonic wave propagation time and the size of the reflected echo when the size of the reflected echo is examined by the probe using the method according to the first embodiment of the present invention.

FIG. 3 is a diagram schematically showing a state in which a bonding defect exists in a part of a bonding portion (bonding surface).

FIG. 4 is a diagram showing a structure of a seismic isolation damper in which a joint state between a lead column body and a flange is examined in a second embodiment of the present invention.

[Explanation of symbols]

1 Lead Column 1a Curved Part 2 Flange 2a Hole for Fixing with Bolt 11 Lead Cylinder (Lead Block) 12 Stainless Steel Material 13 Joining Defect A Joint of Lead Column and Flange (Joint Surface) B Lead Cylinder (Lead Block) And stainless steel joint (joint surface)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tatsuya Futami             5-11-3 Shimbashi, Minato-ku, Tokyo Sumitomo Metals             Within Mining Co., Ltd. (72) Inventor Eisuke Kashiwagi             5-11-3 Shimbashi, Minato-ku, Tokyo Sumitomo Metals             Within Mining Co., Ltd. (72) Inventor Hirofumi Kobune             2-1-2, Kiserejima Island, Amagasaki City, Hyogo Prefecture             Mura Kakoki Co., Ltd. (72) Inventor Naofumi Nakata             2-1-2, Kiserejima Island, Amagasaki City, Hyogo Prefecture             Mura Kakoki Co., Ltd. (72) Inventor Fumio Fukumori             2-1-2, Kiserejima Island, Amagasaki City, Hyogo Prefecture             Mura Kakoki Co., Ltd. (72) Inventor Toshio Ishida             2-1-2, Kiserejima Island, Amagasaki City, Hyogo Prefecture             Mura Kakoki Co., Ltd. (72) Inventor Fumio Oshima             2-1-2, Kiserejima Island, Amagasaki City, Hyogo Prefecture             Mura Kakoki Co., Ltd. (72) Inventor Seikatsu Ikeda             4-27 Akamachicho, Moriguchi City, Osaka Prefecture Daiken Co., Ltd.             Within F term (reference) 2D046 DA12                 2G047 AA06 AB07 AC05 BA03 BC07                       EA11 GG24 GG28                 3J048 AA04 AB01 AC06 BE10 EA38                 3J066 AA26 BA03 BB01 BB04 BC01                       BF01

Claims (7)

[Claims] 1. A seismic isolation damper in which a flange made of a steel material is joined to both end surfaces of a column body made of lead or a lead alloy (hereinafter referred to as "lead column body"), and the lead column body and the flange are joined together. This is an inspection method for judging the quality of the state, in which ultrasonic waves are incident from the flange side to a predetermined inspection area of the joint between the lead column and the flange, and the reflection echo from the joint is detected to reflect A method for inspecting a seismic isolation damper, characterized in that, when the size of the echo is larger than a predetermined threshold value, it is determined that the inspection area has a bonding defect. 2. A seismic isolation damper in which a flange made of steel is joined to both end surfaces of a pillar made of lead or a lead alloy (hereinafter referred to as "lead pillar"), and the lead pillar is joined to the flange. An inspection method for inspecting the condition, in which ultrasonic waves are incident from the flange side to a predetermined inspection area of the joint between the lead column and the flange, and the reflected echo from the joint is detected, All inspection areas that have been determined to have a bonding defect by determining the presence or absence of bonding defects in multiple inspection areas of the joint between the lead column and the flange by the method that determines the presence or absence of a bonding defect in the relevant inspection area from the size The method for inspecting a seismic isolation damper is characterized by determining the quality of the joint state between the lead column body and the flange of the seismic isolation damper as a whole from the ratio of the inspection area in which a joint defect is recognized. 3. A seismic isolation damper in which a flange made of steel is joined to both end surfaces of a pillar made of lead or a lead alloy (hereinafter referred to as "lead pillar") to join the lead pillar and the flange. An inspection method for inspecting a state, comprising: (a) partitioning an entire area of a joint into inspection areas having a predetermined area, and determining the presence or absence of a joint defect in each inspection area; A method for inspecting a seismic isolation damper, comprising determining the quality of the joint between the lead column and the flange of the seismic isolation damper as a whole, based on the ratio of the total area of the inspection area where a joint defect is recognized to the total area. 4. The seismic isolation damper according to claim 1, wherein the flanges are joined to both end faces of the lead column by a method using lead homogen or soldering. Inspection method. 5. The lead column body has a curved portion that curves along one plane.
Inspection method of seismic isolation damper described in any one of 4. 6. A reflected echo from the joint is detected,
When determining the presence / absence of a bonding defect in the inspection area based on the size of the reflected echo, when the size of the first wave reflected echo is 62% or more of the incident ultrasonic wave, the bonding defect is present in the inspection area. The method for inspecting a seismic isolation damper according to claim 1, wherein the seismic isolation damper is inspected. 7. The seismic isolation damper according to any one of claims 1 to 6, which is inspected by the inspection method and is determined to be in a good joint state between the lead column and the flange. Seismic isolation damper.