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Modern manufacturing systems are characterized by the fact that they integrate various machines and work equipment, industrial handling robots, industrial robots performing technological operations (welding, riveting, painting, etc.), transfer systems (conveyors, conveyor belts, automated guided vehicle -AGV), storage systems and inspection stations. The paper presents the way in which the assembly project management of a suspended conveyor system was carried out. Critical path method was used. It has identified the assembly operations, the way they succeed in the technological process of assembly, the duration of the operations and the resources (labor force) necessary for their realization. This information has been processed through Microsoft Project resulting in critical activities (critical path), project duration, the ratio between the available and necessary resources (in the analyzed case a significant deficit of the machinist resource) and the corresponding costs. In order to solve the problem of resource requirements, two solutions were used: leveling resources and supplementing them in order to reduce the duration of critical activities. Finally, a version of the conveyor assembly project management resulted in a balance between costs and duration.

Reverse engineering represents a method to retrieve information from an existing product, information which are then used for designing a new product or to reproduce it in order to make spare parts. In this paper is presented a case study on making a spare part of complex shape from a worn part. There are presented the stages of acquisition of data by scanning, the use of reverse engineering for the realization of the 3D model, the virtual manufacturing and then the machining of the workpiece CNC machine tools.

This paper presents the results of the research about the automation of the metallographic samples preparation and analysis processes. At the University of Oradea the authors designed and made an automated metallographic samples preparation and analysis system. This automated system can achieve polishing, attack by reagents and metallographic analysis. The flexible cell (the automated system) is made of two subsystems. The first subsystem, which is served by an industrial robot, performs the polishing and the sample surface assessment. The second subsystem, also served by an industrial robot, performs the reagent attack and finishes the metallographic analysis in order to determine the microstructure of the sample. The authors have designed a timed Petri nets model in order to assess the performance of the automated system and to identify the possible bottlenecks. The model is made for the case that the system is required to analyse two kinds of samples. The sequences performed by the industrial robots are modelled by transitions with associated timings that are equal to the real time periods taken by the robots to execute the corresponding actions. Other activities, such as grinding polishing, finishing polishing, reagent attack, washing, microscope examining, have been also modelled by means of transitions. The execution of a transition (the completion of a real sequence) is possible if certain conditions are met. These conditions are modelled into the Petri net by means of positions. The number of samples that can be analyzed in a certain time period can be determined by simulation.

Improving the performance of manufacturing systems is the objective of management activities. The paper presents how this objective can be achieved by modeling and simulation. Base on the manufacturing process of the part support bush it is modeled the production line. Modeling is done using the TECNOMATIX PLANT SIMULATION program. Using the first model, by simulation, it was found that the resulting production after eight hours was relatively reduced: 28 pieces. Under these conditions, an additional welding post was introduced in the second model. It results in double the production and also in narrow places. The third model is designed in such a way that bottleneck is eliminated, and there is also an increase in production.

The paper presents how the critical path method is applied to the management of the unique items production. The case of a complex product was taken into consideration: equipment for detergent automatic wrapping. The first step was the signing of the contract with the beneficiary. Then all the activities which lead to the equipment finalization were taken into account: design, supply, execution, assembly, testing and delivery. All these were implemented in the Microsoft Project® software application, which yielded important information for the project manager: critical path, critical activities, finalization deadline and related costs. According to the data of the first version, supplementary resources were added for some critical activities, which yielded the reduction of the project execution duration.

This paper presents how color Petri nets can be used in flexible manufacturing system models.. It is studied the cell from the Faculty of Engineering Management and Technology. In this cell process four parts: two pieces of revolution and two prismatic parts. In a first variant coloured Petri nets model is made without taking into account the time factor. This does not allow a prioritization of processing and the evaluation of manufacturing cycle time. If we consider the factor of time, coloured Petri nets model allows prioritization processing by the fact that each color is associated with a part it can be attach timing. May also be taken into account the processing times through timings associated with the transitions.

The performed studies regarding the cylindrical gears with curved teeth or in V showed that a uniform distribution of the load on the flanks is hard to realise, generally being necessary later finishing processing or modifying the gear by camber or flanking, which suppose supplementary expenses. On the basis of these mentions and taking into account the advantages of curved bevel gear, the purpose of this paper is to present an original study regarding the mathematical model for generation of a curved cylindrical gear with high performances. The cycloidal gear was chosen after a technical and an economical study regarding on the possibility of practical implementation with the lowest production costs using a special device, adapted on a Phauter processing machine of cylindrical gear. This was the main reason for choosing a cycloidal profile from several types of curved teeth (cycloidal arc, circle arc, Archimede’s spiral, involute arc). So, the main aim of the paper is to determine the equations of the flanks of cylindrical wheel with curved teeth in oblong cycloidal arc, in order to establish if the technical generation is possible. The curved cylindrical teeth with cycloidal flanks is generated by rolling with straight mobile line and continuous division by using a milling cutter with 1, 2, 3, 6 groups of knifes equidistantly placed, fixed on an adaptable device on a Phauter processing machine. The two curves which define the flank are simultaneously generated by correlated motions, and the flanks of the wheel part result as a roll of successive positions of generating hook materialized by the cutting edge of the tool. The shape of the contact curve between the conjugated surfaces of generating element and the wheel part can be obtained if you are taking into account the kinematic condition. Using this condition you can determine the relationship between the kinematic, geometric and technological parameters. The line of the flanks is studied in the reference plane and in parallel planes with this, and the profile of the flanks is determined in perpendicular planes on the work piece axis. Based on the parametric equations it was made the simulation program in MATLAB that indicates that this gears can be obtained, and constitutes the first step in practical manufacturing of this kind of gears. By analyzing the obtained shape they result useful conclusions for the manufacturing of the involute-tooth gear with curved oblong cycloidal arc. On the other hand, using Solid Edge it was made the spatial modeling of the cylindrical gear with curved cycloidal teeth that allows next FEA studies regarding on the contact and bending stress.Copyright © 2007 by ASME