1987 Fiscal Year Final Research Report Summary
Research on Qualification Methods of Nondestructive Testing for Welds.
| Project/Area Number |
61302074
|
|---|
| Research Category |
Grant-in-Aid for Co-operative Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
溶接工学
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
HIROSE Sadao Osaka University, Faculty of Engineering, 工学部, 助手 (20029078)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KATO Mitsudki Kyushu Institute of Techuology, Faculty of Engineering, 工学部, 助教授 (90039107)
MUKAE Shizuo Kyushu Institute of Techuology, Faculty of Engineering, 工学部, 教授 (20039027)
URAGAKI Hiroshi Osaka University, Faculty of Engineering, 工学部, 助手 (10107138)
HIRAYAMA Kazuo Osaka University, Faculty of Engineering, 工学部, 助手 (60029147)
|
|---|
| Project Period (FY) |
1986 – 1987
|
| Keywords | Nondestructive Testing / Detectable Limit / Contrast Distribution Area / Ultrasonic Testing / Diffusion Bonding / Mock-up / Magnetic Particle Testing / Yoke Method / Leakage Flux Densities / 極間法 / 漏洩磁束密度 / 有限要素法 |
|---|
| Research Abstract |
Radiographic testing; It is not investigated in detail and in terms of the mass under the practical radiography on the limitation of the minimal defects to be detected. It was discussed in terms of the mass on the detectable limit of such minimal defects of cylindrical defect as a representative of ingot-defect and slit defect as a representative of plate-defect respectively which generally appear on the weld joints, using contrast distribution area of defects on the radiograph.
An experiment was done to vary the radiographic contrast by dual exposure system and to vary the radiation angle by rotating radiography in order to investigate the corresponding reration of detectable limit of defect dimension between cylindrical defect and slit defect.
Ultrasonic testing; Selection of testing method and condition in accordance with kind and size of defect to be detected, require a mockup with artificial defects, sizes and location of which are well known. Fablication procedure of mockup by applying diffusion bonding was investigated and carried out. The results of ultrasonic testing of mockups show that measured data coincide very closely with calculated of designed values in terms of echo amplitude from a defect, location and range of distributed multiple defects.
Magnetic particle testing; New methods for estimating quantatively dimensions of defects were proposed when yoke method was applied. It is very effective for estimating the dimensions of defects to use a schematical solution when both maximum values of horizontal component and those of vertical component of leakage flux densities are numerically given for several defect breadths and defect depths by FEM.The defect length is regarded as infinite when this is longer than about 30mm. The leakage flux densities decrease with decreasing the defect length shorter than 30mm, and lower to about 65% of the infinite defect for the defect length of 5mm.
|
