Search

Purpose: The purpose of the degree project was to investigating fire protection work during construction at various companies and proposing improvement proposals to reduce the risk of fire at construction sites. Method: The method on which the thesis project was based on was a literature study, interviews and document analysis. The literature study has been carried out to gain in-depth knowledge regarding the fire protection during the construction phase. The interview study was conducted at different construction companies to get an idea of ​​how the different companies handle fire safety at construction sites. The document analysis has been carried out with the help of various companies requirements documents, which form the basis for the fire protection work at the construction sites. Results: The results present the companies fire protection work during construction. Prior to the start of construction, a fire protection description is projected that covers how to build to prevent fire safety, it also covers the how parts of the workplace should be designed. The fire protection that proved to exist mostly consists of two mutually independent escape routes with clearly visible escape signs, a dedicated collection point and strategically placed hand-held fire extinguishers that should be within a range of 25 meters. Hot work, electrical causes and arson have emerged as a recurring shortage and cause of most fires occurring at construction sites. There is room for improvement by, among other things, spending more time in planning, introducing a practice on fire and evacuation alarms and creating the company's fire protection description in connection with the production of the A-drawings. Conclusions: In conclusion, there are opportunities for improvement, but unfortunately nothing has been implemented in practice.

Additive manufacturing (AM) brings the possibility to produce tools with a complex design of the cooling channels to achieve desired properties in the working piece. However, AM of tool steels can be challenging due to the residual stresses and crack formation which may be mitigated by optimizing process parameters. In this study, process parameters development in the laser powder bed fusion (L-PBF) of a martensitic hot work tool steel was under investigation. Having power, scanning speed and hatch distance as variables, a design of experiment was performed to map a process window to produce dense components. In addition, the same sets of process parameters were applied at different preheating temperatures to study and discuss the effect of three preheating temperatures on the porosity, microstructure and hardness of the manufactured components. The characterization of the parts was done using optical and scanning electron microscopy, x-ray diffraction and micro-hardness test. The results showed that the martensitic hot work tool steel can be manufactured with L-PBF with high densities above 99.95%. © 2022 The Authors. Published by Elsevier B.V.

Purpose: The purpose of the degree project was to investigating fire protection work during construction at various companies and proposing improvement proposals to reduce the risk of fire at construction sites. Method: The method on which the thesis project was based on was a literature study, interviews and document analysis. The literature study has been carried out to gain in-depth knowledge regarding the fire protection during the construction phase. The interview study was conducted at different construction companies to get an idea of ​​how the different companies handle fire safety at construction sites. The document analysis has been carried out with the help of various companies requirements documents, which form the basis for the fire protection work at the construction sites. Results: The results present the companies fire protection work during construction. Prior to the start of construction, a fire protection description is projected that covers how to build to prevent fire safety, it also covers the how parts of the workplace should be designed. The fire protection that proved to exist mostly consists of two mutually independent escape routes with clearly visible escape signs, a dedicated collection point and strategically placed hand-held fire extinguishers that should be within a range of 25 meters. Hot work, electrical causes and arson have emerged as a recurring shortage and cause of most fires occurring at construction sites. There is room for improvement by, among other things, spending more time in planning, introducing a practice on fire and evacuation alarms and creating the company's fire protection description in connection with the production of the A-drawings. Conclusions: In conclusion, there are opportunities for improvement, but unfortunately nothing has been implemented in practice.

Additive manufacturing (AM) brings the possibility to produce tools with a complex design of the cooling channels to achieve desired properties in the working piece. However, AM of tool steels can be challenging due to the residual stresses and crack formation which may be mitigated by optimizing process parameters. In this study, process parameters development in the laser powder bed fusion (L-PBF) of a martensitic hot work tool steel was under investigation. Having power, scanning speed and hatch distance as variables, a design of experiment was performed to map a process window to produce dense components. In addition, the same sets of process parameters were applied at different preheating temperatures to study and discuss the effect of three preheating temperatures on the porosity, microstructure and hardness of the manufactured components. The characterization of the parts was done using optical and scanning electron microscopy, x-ray diffraction and micro-hardness test. The results showed that the martensitic hot work tool steel can be manufactured with L-PBF with high densities above 99.95%. © 2022 The Authors. Published by Elsevier B.V.

Additive manufacturing (AM) brings the possibility to produce tools with a complex design of the cooling channels to achieve desired properties in the working piece. However, AM of tool steels can be challenging due to the residual stresses and crack formation which may be mitigated by optimizing process parameters. In this study, process parameters development in the laser powder bed fusion (L-PBF) of a martensitic hot work tool steel was under investigation. Having power, scanning speed and hatch distance as variables, a design of experiment was performed to map a process window to produce dense components. In addition, the same sets of process parameters were applied at different preheating temperatures to study and discuss the effect of three preheating temperatures on the porosity, microstructure and hardness of the manufactured components. The characterization of the parts was done using optical and scanning electron microscopy, x-ray diffraction and micro-hardness test. The results showed that the martensitic hot work tool steel can be manufactured with L-PBF with high densities above 99.95%. © 2022 The Authors. Published by Elsevier B.V.

Additive manufacturing (AM) brings the possibility to produce tools with a complex design of the cooling channels to achieve desired properties in the working piece. However, AM of tool steels can be challenging due to the residual stresses and crack formation which may be mitigated by optimizing process parameters. In this study, process parameters development in the laser powder bed fusion (L-PBF) of a martensitic hot work tool steel was under investigation. Having power, scanning speed and hatch distance as variables, a design of experiment was performed to map a process window to produce dense components. In addition, the same sets of process parameters were applied at different preheating temperatures to study and discuss the effect of three preheating temperatures on the porosity, microstructure and hardness of the manufactured components. The characterization of the parts was done using optical and scanning electron microscopy, x-ray diffraction and micro-hardness test. The results showed that the martensitic hot work tool steel can be manufactured with L-PBF with high densities above 99.95%. © 2022 The Authors. Published by Elsevier B.V.

Additive manufacturing (AM) brings the possibility to produce tools with a complex design of the cooling channels to achieve desired properties in the working piece. However, AM of tool steels can be challenging due to the residual stresses and crack formation which may be mitigated by optimizing process parameters. In this study, process parameters development in the laser powder bed fusion (L-PBF) of a martensitic hot work tool steel was under investigation. Having power, scanning speed and hatch distance as variables, a design of experiment was performed to map a process window to produce dense components. In addition, the same sets of process parameters were applied at different preheating temperatures to study and discuss the effect of three preheating temperatures on the porosity, microstructure and hardness of the manufactured components. The characterization of the parts was done using optical and scanning electron microscopy, x-ray diffraction and micro-hardness test. The results showed that the martensitic hot work tool steel can be manufactured with L-PBF with high densities above 99.95%. © 2022 The Authors. Published by Elsevier B.V.

Additive manufacturing (AM) brings the possibility to produce tools with a complex design of the cooling channels to achieve desired properties in the working piece. However, AM of tool steels can be challenging due to the residual stresses and crack formation which may be mitigated by optimizing process parameters. In this study, process parameters development in the laser powder bed fusion (L-PBF) of a martensitic hot work tool steel was under investigation. Having power, scanning speed and hatch distance as variables, a design of experiment was performed to map a process window to produce dense components. In addition, the same sets of process parameters were applied at different preheating temperatures to study and discuss the effect of three preheating temperatures on the porosity, microstructure and hardness of the manufactured components. The characterization of the parts was done using optical and scanning electron microscopy, x-ray diffraction and micro-hardness test. The results showed that the martensitic hot work tool steel can be manufactured with L-PBF with high densities above 99.95%. © 2022 The Authors. Published by Elsevier B.V.