| 1. |
- Ebrahimi, Amir Hossein, 1976, et al.
(författare)
-
Automated analysis of interdependencies between product platforms and assembly operations
- 2016
-
Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 44, s. 67-72
-
Konferensbidrag (refereegranskat)abstract
- Configurable products, like vehicles, face the challenge of handling all possible variants which are needed to answer the various customer needs. For these configurable products the support of all variants need to be addressed both by the design phase and the production phase. The product design phase and the production phase are linked together via operations. These operations model how each part of the bill-of-material is assembled to the final product. Operations also have inner relations among themselves, namely the precedence constraints, stating the order in which different parts can be assembled. Considering only the precedence constraints a product can generally be assembled in various different ways. It is through line balancing that the operations are assigned to different stations and/or assembly workers. The bill-of-material for each configurable product might be different with each variant, which will result in different set of operations. However, due to the precedence rules among the operations not all sets of operations might be possible to complete. The contribution in this paper is a automated method that can determine if all possible product variants can be successfully assembled while still satisfying precedence constraints between operations. The paper also includes an industrial example which further exemplifies the needed input for the method and the possible method outputs as a result of introducing a new variant to the product platform.
|
|
| 2. |
- Johansson, Pierre, 1986
(författare)
-
Challenges in Global Multi-Variant Serial Production - A Study of Manufacturing Engineering Processes
- 2016
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Global manufacturing companies have hard times to manage their global production networks as dispersion in their networks increases. Such dispersion is caused by the increasing level of product variety and more parameters to control as the networks grow. Handling product variety becomes more difficult as products become more complex and integrated. Product variety and its impact on productivity have been studied for several years. Those studies show that product variety has negative impact on productivity. There are no signs that product variety will decrease in the future. Nor are there any signs showing that the size of global product networks will decrease over time. Therefore, it is important to understand how product variety affects global production networks.The aim of this thesis is to investigate how global manufacturing companies operate their production networks in terms of manufacturing engineering processes and operational performance with respect to product variety. Due to the size of global production networks, engineering processes and systems tend to be dispersed. Therefore, the focus of this thesis is on studying manufacturing engineering processes in terms of standards for creating assembly work instructions for manual assembly and the effects of high product variety on operational performance in the same production network. In this study similarities and dissimilarities in such processes are mapped within one global production network.Four different cases studies have been designed and conducted collecting important data defining the setup for the investigated production network. Questionnaires, interviews and production data are used to map current manufacturing engineering processes and to study the effects of high product variety on operational performance. Results from the case studies show that the studied production network handles high levels of product variety and that the manufacturing engineering processes are highly dispersed due to lack of global standards. The high level of product variety has negative impact on operational performance as operators are facing unfamiliar product variants on a daily basis. Furthermore, the high level of product variety makes it more difficult for manufacturing engineering to create better and more supportive assembly work instructions.Future research activities should focus more on early phases of the engineering process. By studying the engineering process in more detail, a mature information model can be created defining (1) what information is used, (2) by whom it is used, (3) where in the process it is used and (4) for what purpose the information is used. Such an information model is essential to be able to develop better methods to handle high product variety in global production networks.
|
|
| 3. |
- Johansson, Pierre, 1986, et al.
(författare)
-
Global Truck Production - The Importance of Having a Robust Manufacturing Preparation Process
- 2016
-
Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 57, s. 631-636
-
Konferensbidrag (refereegranskat)abstract
- Global production networks (GPN) are generally hard to manage due to spread of processes and systems. The amount of product variants adds to the complexity. This study, based on interviews and questionnaires, shows an improvement possibility by standardizing the process for preparing assembly work instructions on a global level. Furthermore, several factors that are negatively affected by not having a standard implemented are identified. The empirical findings suggest that a standardized manufacturing preparation process could improve knowledge and information transfer within a GPN. A standardization of the manufacturing preparation process would also decrease diversification in terms of double work and possibility to simplify infrastructure and to reduce the amount of support systems used.
|
|
| 4. |
- Johansson, Pierre, 1986, et al.
(författare)
-
Multi-Variant Truck Production - Product Variety and its Impact on Production Quality in Manual Assembly
- 2016
-
Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 54, s. 245-250
-
Konferensbidrag (refereegranskat)abstract
- The trend of diversifying product portfolios increases the challenges for global manufactures to keep production processes robust and maintainhigh quality. Manufacturing trucks with high level of customization increases the vulnerability to quality deviations in the assembly process.By studying eight manual assembly stations, at a truck manufacturing plant, it was found that high product variety has negative impact onproduction quality and that high production complexity is connected to high product variety. The study also showed that if operators do nothave proper information systems, with accurate data, they need to trust their own knowledge and skills. Results imply that more research isneeded to address how the production of products with high variety can be handled to lower the exposure to quality deviations.
|
|
