Friction welding of thin walled zircaloy-4 tubes for the nuclear industry
- Authors: Koloi, Nthatisi Dinah
- Date: 2017
- Subjects: Friction welding Zirconium alloys
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/18794 , vital:28724
- Description: This work reports on the process development of solid state welding as an alternative joining process for assembling Zircaloy-4 fuel rod components for the nuclear industry. A typical fuel rod consists of a thin tube that is blocked at both ends by end-caps. The welding of the thin wall tubes onto the end-caps is currently accomplished by employing fusion techniques. Due to limited thin wall Zircaloy-4 tube supplied, preliminary welding was initially performed with thin wall 316L stainless steel tube for the development of a joint geometry and establishment of an experimental welding and testing setup. A suitable joint geometry that would achieve higher static strength equal or above that of the parent material, as well as complete circumferential bonding was investigated through welding a tube on different volume interface geometries of the end-caps. Higher joint efficiency was obtained from a tube-to-tube joint geometry that allowed sufficient frictional heat input at the interface. Consequently, the successful joint geometry was employed to develop a friction welding process for the joining of thin wall Zircaloy-4 tubes. The influential process parameters, axial force, rotational speed and upset distance were varied during the investigation. The completed weld joints were evaluated by visual, metallurgical and mechanical means. Successful welds showed complete circumferential bonding and high joint efficiency that was above the parent plate material as well as parent tube material. The evaluation of the microstructure showed transformation of grain structure on the heat affected zone (HAZ) and friction weld zone when compared to the parent materials. Even though, this work could not resolve inner flash formation, there is enough evidence that friction welding can be used for assembling fuel rod components in the nuclear industry.
- Full Text:
- Date Issued: 2017
- Authors: Koloi, Nthatisi Dinah
- Date: 2017
- Subjects: Friction welding Zirconium alloys
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/18794 , vital:28724
- Description: This work reports on the process development of solid state welding as an alternative joining process for assembling Zircaloy-4 fuel rod components for the nuclear industry. A typical fuel rod consists of a thin tube that is blocked at both ends by end-caps. The welding of the thin wall tubes onto the end-caps is currently accomplished by employing fusion techniques. Due to limited thin wall Zircaloy-4 tube supplied, preliminary welding was initially performed with thin wall 316L stainless steel tube for the development of a joint geometry and establishment of an experimental welding and testing setup. A suitable joint geometry that would achieve higher static strength equal or above that of the parent material, as well as complete circumferential bonding was investigated through welding a tube on different volume interface geometries of the end-caps. Higher joint efficiency was obtained from a tube-to-tube joint geometry that allowed sufficient frictional heat input at the interface. Consequently, the successful joint geometry was employed to develop a friction welding process for the joining of thin wall Zircaloy-4 tubes. The influential process parameters, axial force, rotational speed and upset distance were varied during the investigation. The completed weld joints were evaluated by visual, metallurgical and mechanical means. Successful welds showed complete circumferential bonding and high joint efficiency that was above the parent plate material as well as parent tube material. The evaluation of the microstructure showed transformation of grain structure on the heat affected zone (HAZ) and friction weld zone when compared to the parent materials. Even though, this work could not resolve inner flash formation, there is enough evidence that friction welding can be used for assembling fuel rod components in the nuclear industry.
- Full Text:
- Date Issued: 2017
The experiences of men who have sex with men (MSM) in accessing public primary health care services in the Eastern Cape province, South Africa
- Authors: Kose, Zamakayise Zukisa
- Date: 2016
- Subjects: Primary health care -- South Africa -- Eastern Cape , Gay men -- South Africa -- Eastern Cape , Discrimination -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/4698 , vital:20652
- Description: Background: Research has shown that men who have sex with men (MSM) experience stigma, discrimination, negative and judgmental attitudes and homophobia when accessing health care services. This has resulted in limited uptake of existing HIV and AIDS services. Further, the experiences serve as barriers to seeking and accessing public primary health care services. Negative psychological outcomes and in unique cases, adverse mental health outcomes have resulted from these experiences. Aim: The study aimed to explore and describe the experiences of a sample of MSM when accessing public health care services in Nelson Mandela Bay Municipality (NMBM). Method: A purposive sample of twenty-one MSM aged 22 to 30+ years, mainly black who lived in NMBM participated in semi-structured in-depth interviews. The study used the exploratory-descriptive qualitative design and thematic analysis was used to summarize findings. Findings: Findings from the study showed that MSM experience internalized stigma, perceived stigma, experienced stigma and HIV related stigma, resulting in minority stress. Experiences with health care services included long waiting time, lack of supplies, being attended to by different health care providers, health care provider insensitivity, comfort with health care provider and a need for integrating health services for MSM with general health services. Effects of stigma expressed by the men were non-disclosure of sexual orientation, reluctance to use public health facilities, negative mental health outcome and conformity to society. Conclusion: The study suggests that MSM public health services need to be improved and barriers to health access among MSM need to be addressed. Lastly, there is a need to address the health, psychological and social effects of stigma suffered by MSM.
- Full Text:
- Date Issued: 2016
- Authors: Kose, Zamakayise Zukisa
- Date: 2016
- Subjects: Primary health care -- South Africa -- Eastern Cape , Gay men -- South Africa -- Eastern Cape , Discrimination -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/4698 , vital:20652
- Description: Background: Research has shown that men who have sex with men (MSM) experience stigma, discrimination, negative and judgmental attitudes and homophobia when accessing health care services. This has resulted in limited uptake of existing HIV and AIDS services. Further, the experiences serve as barriers to seeking and accessing public primary health care services. Negative psychological outcomes and in unique cases, adverse mental health outcomes have resulted from these experiences. Aim: The study aimed to explore and describe the experiences of a sample of MSM when accessing public health care services in Nelson Mandela Bay Municipality (NMBM). Method: A purposive sample of twenty-one MSM aged 22 to 30+ years, mainly black who lived in NMBM participated in semi-structured in-depth interviews. The study used the exploratory-descriptive qualitative design and thematic analysis was used to summarize findings. Findings: Findings from the study showed that MSM experience internalized stigma, perceived stigma, experienced stigma and HIV related stigma, resulting in minority stress. Experiences with health care services included long waiting time, lack of supplies, being attended to by different health care providers, health care provider insensitivity, comfort with health care provider and a need for integrating health services for MSM with general health services. Effects of stigma expressed by the men were non-disclosure of sexual orientation, reluctance to use public health facilities, negative mental health outcome and conformity to society. Conclusion: The study suggests that MSM public health services need to be improved and barriers to health access among MSM need to be addressed. Lastly, there is a need to address the health, psychological and social effects of stigma suffered by MSM.
- Full Text:
- Date Issued: 2016
An assessment of the recruitment and selection strategies used in the sales department of Old Mutual Group Schemes in the Eastern Cape
- Authors: Booi, Solomzi Kaya
- Date: 2005
- Subjects: Employees recruiting , Insurance agents -- Recruiting -- South Africa -- Port Elizabeth , Old Mutual (Cape Town, South Africa) Employees , Group insurance
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:9261 , http://hdl.handle.net/10948/150 , Employees recruiting , Insurance agents -- Recruiting -- South Africa -- Port Elizabeth , Old Mutual (Cape Town, South Africa) Employees , Group insurance
- Description: The aim of this research was to assess the recruitment and selection strategies used in the sales department of Old Mutual Group Schemes (OMGS) in the Eastern Cape. The company hopes to stem the high labour turn over in OMGS. After the Labour Relations Act 66 of 1995 (LRA) and Employment Equity Act 55 of 1998 (EEA) were promulgated, organisations in this country introduced new recruitment and selection policies. The challenge to most organisations is the implementation of these policies by managers. The requirements of these two legislations create problems for small companies because of the high costs involved especially in the implementation stages. The organisation incurs costs in the development of the new processes and the training of staff. Even after the new processes, labour turnover did not improve in OMGS. Senior management is trying any means possible to rectify the situation. The company policy was examined against the literature available and the recruitment and selection processes of different authors were investigated. The findings indicated that some steps in the recruitment and selection processes were not followed. It was recommended that the organisation use more recruitment sources to broaden the scope of accessing more suitable applicants.
- Full Text:
- Date Issued: 2005
- Authors: Booi, Solomzi Kaya
- Date: 2005
- Subjects: Employees recruiting , Insurance agents -- Recruiting -- South Africa -- Port Elizabeth , Old Mutual (Cape Town, South Africa) Employees , Group insurance
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:9261 , http://hdl.handle.net/10948/150 , Employees recruiting , Insurance agents -- Recruiting -- South Africa -- Port Elizabeth , Old Mutual (Cape Town, South Africa) Employees , Group insurance
- Description: The aim of this research was to assess the recruitment and selection strategies used in the sales department of Old Mutual Group Schemes (OMGS) in the Eastern Cape. The company hopes to stem the high labour turn over in OMGS. After the Labour Relations Act 66 of 1995 (LRA) and Employment Equity Act 55 of 1998 (EEA) were promulgated, organisations in this country introduced new recruitment and selection policies. The challenge to most organisations is the implementation of these policies by managers. The requirements of these two legislations create problems for small companies because of the high costs involved especially in the implementation stages. The organisation incurs costs in the development of the new processes and the training of staff. Even after the new processes, labour turnover did not improve in OMGS. Senior management is trying any means possible to rectify the situation. The company policy was examined against the literature available and the recruitment and selection processes of different authors were investigated. The findings indicated that some steps in the recruitment and selection processes were not followed. It was recommended that the organisation use more recruitment sources to broaden the scope of accessing more suitable applicants.
- Full Text:
- Date Issued: 2005
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