A Branch-and-Price Algorithm for Balancing Two-Sided Assembly Lines with Zoning Constraints

Two-sided assembly lines are widely used in the large-size product manufacturing industry, especially for automotive assembly production. Balancing the assembly line is significant for assembly process planning and assembly production. In this study, we develop a novel and exact method to optimize the two-sided assembly line balancing problem with zoning constraints (TALBz), in which the aim is to minimize the number of mated-stations considering the task restrictions. A mixed-integer programming model is employed to exactly describe the TALBz problem. To strengthen the computational efficiency, we apply Dantzig–Wolfe decomposition to reformulate the TALBz problem. We further propose a branch-and-price (B&P) algorithm that integrates the column generation approach into a branch-and-bound frame. Both the benchmark datasets with zoning constraints and without zoning constraints are tested to evaluate the performance of the B&P algorithm. The numerical results show that our proposed approach can obtain optimal solutions efficiently on most cases. In addition, experiments on the real-world datasets originating from passenger vehicle assembly lines are conducted. The proposed B&P algorithm shows its advantage in tackling practical problems with the task restrictions. This developed methodology therefore provides insight for solving large-scale TALBz problems in practice.

Methods of evaluation of production and technological work with shipbuilding

Оценка и анализ производственно-технологических работ судостроительных предприятий обусловлен необходимостью обеспечения конкурентоспособности вновь создаваемых объектов морской техники с показателями качества на уровне лучших мировых образцов с одновременным повышением темпов технико-экономического развития их производства. Названная проблема диктует необходимость адекватной оценки состояния технического оснащения производства, а также наиболее эффективных направлений вложения средств на техническое перевооружение. Техническое оснащение производства во многом зависит от уровня автоматизации, механизации технологических процессов, объёмов ручных работ, конструктивно-технологических особенностей создаваемых объектов морской техники, серийности производства и т.д. Для судостроения, судового машиностроения с учётом единичного и мелкосерийного производства характерна высокая доля ручного труда, особенно при выполнении механомонтажных работ. В статье предложен принципиально новый подход к оценке производственно-технологических работ (уровней технического оснащения производства) судостроительных предприятий. Приведены результаты расчётов и оценки на примере переделов (видов работ) механомонтажного производства для группы отечественных судостроительных предприятий. Предложенный метод оценки производственно-технологических работ (потенциалов) универсален для любых видов судостроительных и машиностроительных работ. Evaluation and analysis of production and technological works of shipbuilding enterprises is conditioned by the need to ensure the competitiveness of newly created marine equipment facilities with quality indicators at the level of the world's best samples, while increasing the pace of technical and economic development of their production. This problem dictates the need for an adequate assessment of the state of technical equipment of production, as well as the most effective ways of investing funds for technical re-equipment. The technical equipment of production largely depends on the level of automation, mechanization of technological processes, the volume of manual work, the design and technological features of the created objects of marine equipment, serial production, etc. For shipbuilding, marine engineering, taking into account single and small-scale production, a high proportion of manual labor is characteristic, especially when performing mechanical installation work. The article proposes a fundamentally new approach to the assessment of production and technological works (levels of technical equipment of production) of shipbuilding enterprises. The results of calculations and estimates on the example of repartitions (types of work) are given mechanical assembly production for a group of domestic shipbuilding enterprises. The proposed method of evaluation of production and technological works (potentials) is universal for all types of shipbuilding and machine-building works.

Integration of Waste Assessment Model and Lean Automation to Improve Process Cycle Efficiency in the Automotive Industry

Purpose: This study aims to improve Process Cycle Efficiency (PCE) by reducing waste in the assembly production line. This research is a case study conducted in a four-wheel vehicle manufacturing company to create a Lean production system. Methodology/Approach: This study uses the Waste Assessment Model (WAM) and Lean Automation integration methods carried out by 5 expert judgements in the selected four-wheeled vehicle industry. Findings: Based on the WAM method, this study found the biggest waste on the assembly line, namely transportation with a percentage of 20.44%. Improvements made with Lean Automation can increase the value of PCE from 56.76% to 63.62%. Research Limitation/Implication: This research is limited to one model, namely Multi Purpose Vehicle (MPV). This research provides benefits for companies related to waste reduction. For similar companies, this research can be input for manufacturing practitioners in improving manufacturing performance to compete in the global market. This Lean production can reduce manpower which has an impact on saving production costs. Originality/Value of paper: This paper provides added value related to the application of Lean terminology which aims to improve industrial automation-based manufacturing companies.

Control System of Assembly Production Organizational and Technological System of Automotive Cluster Factories

New term “Assembly Production Organizational and Technological System” is proposed. The model of Assembly Production Organizational and Technological System developed by the authors is described. In the model, this system is considered as a set of subsystems included in it: Assembly Tools Subsystem, Calibration Equipment Subsystem, Spare Tools and Parts Subsystem. Control system of the Assembly Production Organizational and Technological System is described. Developed by the authors model of Assembly Tools Set Element, which is a part of the Assembly Tools Subsystem is described. Developed by the authors classification of elements of assembly tools set is provided. The authors divide the assembly tools set into the following groups of equipment: torque wrenches, non-programmable screwdrivers and nutrunners, multispeed programmable screwdrivers and nutrunners, tooling and adaptors. Assembly tools for tightening threaded joints are divided into 3 groups according to the level of automation of the tightening process. These groups are divided into subgroups according to the principles developed by the authors. Developed classification of elements of assembly tools set is expedient to be used in automotive cluster assembly factories and other factories which have a similar assembly tools set structure.

Optimization of Assembly Production Based on Imitation of Petri Nets

The paper describes the approach to solving the problem of optimal planning of the production process. A discrete production system represented by the operations of machining, welding and painting was chosen as the object of research. The study states the problem of optimization of assembly production, which contains a typical criterion of optimality. A mechanism for meeting the criterion using a simulation model based on a Petri net is determined. The rules for developing feedback on the state of the network model and a method for controlling the simulation of the Petri net based on the analysis of its states are given. A binary function is used to analyze the states of the model. The developed approach to process optimization develops the theory of Petri nets, makes it more suitable for modeling complex systems with a branched structure and a large number of interconnections, which is a typical situation for production systems. The most universal approaches of control theory, e.g. feedback principle, are used, which implies a significant degree of universality and replicability of the approach. On the basis of the developed theoretical provisions, a test example is presented that characterizes the effect of their application. The presence of assembly production at most mechanical-engineering enterprises determines the high practical significance of the developed approach

METHODS AND MODELS OF QUALITY MANAGEMENT OF MODULAR DESIGN OF ASSEMBLY PRODUCTION OF UNMANNED AERIAL VEHICLES

The article is devoted to the creation of a method for preparing an unmanned aerial vehicle for implementation as a finished packaged product. To achieve the goal, modern methods of standardization and quality control are used.

IMULATION MODELING OF PROCESSES OF UNIT-ASSEMBLY PRODUCTION OF AIRCRAFT PRODUCTS

The article presents a universal simulation model of aggregate and Assembly production processes based on IDEF0 methods and numerical modeling methods. The problem statement is formed as follows: it is necessary to analyze the existing simulation tools, structure the Assembly production processes into separate classes and subclasses, describe the processes using the IDEF0 method, create a simulation model of the aggregate-Assembly production process with a link between economic and labor costs. The total labor intensity of Assembly processes and economic costs were considered as optimization criteria in this study. Numerical modeling and optimization of workflow parameters were performed in the AnyLogic simulation environment. The obtained simulation models can be used in the future in the management system of aviation enterprises, as well as in other production areas where the product is a complex system.

Formalization of requirements to precision products at technological preparation stages of machine-assembly production

The improvement of mathematical and methodical support to realize an enlarged unit of design procedures of the analysis of requirements to the assembly of precision products being a part of a complex approach is considered. It is shown that this ensures the efficient fulfillment of assembly operations on the basis of the tie between a technological preparation of processing and assembly production of precision products.