The production process is a complex technological action that can be organized in various ways and means. The work of the enterprise in the conditions of mass production is today considered the most efficient, but at the same time demanding in terms of labor, organizational and material costs. In a general sense, in-line production is a format of production activity in which the principles of rhythm and repeatability of technological coordinated operations come to the fore. The essence of this process, its features, organization methods, etc. will be examined in more detail below.
Process concept
At the heart of any production is a model of the organization of the main, servicing and auxiliary processes, thanks to which the work of the enterprise is carried out, aimed at the creation of certain products. Regarding the organizational model, the used tools (machines, conveyors, tools) can be considered as objects of the organization that are in direct connection with the objects of production, that is, manufactured products.
To a large extent, the person still performs the functions of the link between the different elements of production within the organizational model. As a maximum, he directly participates in the manufacturing processes, at least - controls equipment that implements technological operations.
Among the features of the in-line production method, emphasis is placed on the automation of work activities with minimal human involvement. The possibilities of organizing uninterrupted automated production can be realized for the most part in the basic technological processes related to the material transformation of conditional workpiece into a commodity relationship. For example, the manufacture of furniture at the stages of lumber processing is the main working process of a furniture factory, which today is carried out at large enterprises on machines under numerical control. Conversely, the maintenance and auxiliary processes of production activities are carried out mainly by the working personnel directly, since most of these actions require the adoption of complex non-standard decisions.
The essence of continuous production
The model of production activity in a flow form is based on the rhythmic repeatability of a certain set of technological operations that are performed in the corresponding workshops at workplaces. Coordination between separate operations can occur at different technical and organizational levels with separation in time and space. In other words, in-line production is a pre-thought out algorithm of actions aimed at manufacturing the target products of the enterprise.
For a clearer understanding of the form of production under consideration, the principle of a non-flow model can be cited as an example. In this case, the organization of production can be applied both in a single and in a serial format for manufacturing products. The difference lies in the fact that the continuous production technology is based on the interconnection of several groups of work operations. In the model of non-continuous production, workshop sections are organized according to the principle of performing similar and rhythmic, but not coordinated processes. Manufacturing takes place between operations, and processed items and blanks are sent along complex routes to the next production levels without pairing.
Features of in-line production
Among the distinguishing features of the technological organization of in-line production are the following:
- Workplaces serve operations performed in relation to the same objects with similar technical and structural characteristics. In more complex models, the work of in-line production allows a change in the processing format in a certain range of modes. That is, the conveyor line in the framework of even one technological process can be reoriented to different groups of processed items.
- The configuration of the location of workplaces is selected depending on the production logistics. A clear hierarchy of sequences is observed when performing technological operations.
- The transition of an object from one work unit to another can be carried out both in a piece-wise format and in a party, but in any case, if possible, the general rhythm of production should be maintained.
- The main and part of the auxiliary operations are performed in a mechanized or automated mode of continuous production. This allows you to withstand a high rate of executable processes, but does not exclude the possibility of a technological break, the admissible parameters of which are calculated in advance in the algorithm of the current model.
Principles of Stream Production
Achieving sufficient production efficiency "on the stream" is possible only subject to a number of principles of technological organization of the workflow, including:
- The principle of continuity. The dependence between the individual production lines on the basis of time is minimized. For example, the pace of one workplace in this case cannot become the cause of cyclical delays of other production sites.
- The principle of parallelism. The finished products and billets in parallel with the production method move along technological routes in parallel, which also contributes to the implementation of the principle of continuity without delay.
- The directivity principle. Both workplaces and equipment are placed in a clear order corresponding to the manufacturing process.
- The principle of specialization. The separation of production functions between separate groups of production lines is provided. That is, the universality of jobs is excluded in terms of the ability to perform various operations.
- The principle of rhythm. Within the framework of the functioning of one workplace, the cycle of operations is ensured not only with the release of one product, but also in the mode of production of production batches. Thanks to this principle, mass production is organized with a planned approach to mass production of the target product.
Types of production lines
Organization of production on the basis of production lines may include different groups of work units. In relation to them, several classification features are distinguished:
- By degree of specialization. The line can be single and multi-subject. In the first case, it is supposed to perform operations with one type of product during a certain technological period. Multi-subject lines are usually used in in-line production processes with insufficient capacity utilization for processing a single product. Accordingly, parallel execution of additional processes is organized with a different processing format.
- By the method of maintaining the working pace. Production lines can work in a free rhythm or with a clear time schedule. According to the principle of continuity, in order to reduce the cost of production, a continuous flow regulated rhythm is more often used. The free pace of production is established in cases where the company, due to the instability of connecting capacities or raw materials, cannot maintain stable work processes.
- By type of vehicles used. Conveyors on which manufacturing items move can operate continuously or discretely. The mode of movement depends on the pace, power load and other characteristics of the production operations.
- By degree of mechanization. Mostly in the classification of mass continuous production we are talking about the level of automation. The same conveyors and processing equipment can operate under the control of automatic and semi-automatic controllers with a centralized, dispatch or synchronized principle of operation.
Production line equipment
The technical basis of in-line production is formed by different types of conveyors - for example, plate, belt, suspension and chain. They provide the movement of objects from one work node to another in a given rhythm. Workplaces are equipped with technological equipment that performs the tasks of processing workpieces, assembling parts and consumables. It can be machines, as well as devices for providing thermal, chemical and mechanical effects. In aggregate-stream production, a special role is given to auxiliary vehicles, due to which the functions of the bundle between different work units are performed. In particular, these can be ramps, roller tables, telphers, descents, etc. This equipment also functions according to different principles - with movement on rails, in the mode of mobile or free movement under the direct control of the operator.
Organization of a continuous production line
Technologically, it is the most developed form of production in which the items of manufacture pass from one work unit to another without delay, and the time periods for performing one operation correspond to the general tact of work. For example, in this mode, the time taken by the product to pass through one stage of processing corresponds to the time spent on the previous stages of the operation, which virtually eliminates the pause between the parts arriving at the work sites. The sequence of parallel operating and releasing units within the framework of a given cycle of in-line production is observed. The organization of such a regime is quite demanding on the initial calculations of the addressing system. Usually, a schedule is drawn up for it with a clear definition of the stroke of the conveyor line, its power and speed.
Organization of continuous flow production
If due to various reasons at the production site it is impossible to maintain a common cycle of technological operations, then an adjustment is made for possible pauses and breaks. Otherwise, the risk of receiving defective products or disruption of the supply chain is increased. Due to the multiplicity or inequality of operations to the general rhythm, the organization of in-line production of this type provides for the existence of interoperational backlogs. This is a kind of discontinuity coefficient, expressed as the downtime of equipment in a particular area. In technical terms, the organization of discontinuous production is distinguished by the presence of distribution conveyors, thanks to which the necessary intermediate production processes are optimized, which determine the very presence of working backlogs. As a rule, continuous flow lines are organized at large enterprises with large distances between individual processing units.
Features of multi-subject continuous production lines
The main difference of this configuration of the production line is its wide specialization in the range of products. This characteristic determines the complexity of the organization of production with the need to ensure interoperable backlogs. At the same time, each workplace can produce several different parts, but also having related structural parameters. Methods for alternating operations and parts may vary. For example, group (sequential) and sequentially-partionic principles of alternation are distinguished, which are selected on the basis of the current tasks of continuous production. The method of organizing multi-subject lines is also characterized by large tacts for performing operations in the stream, which gives additional advantages for synchronizing technological processes.
Conclusion
Serial production as such is an economically viable form of work for most large industrial enterprises. But along with this, high financial and logistical costs are expected, without optimizing which production activities will be ineffective. In this regard, in-line production is the optimal format for serial production of complex products that require the use of many technological operations. Another thing is that for the organization of such production lines special conditions must be met initially. Among them, one can note wide opportunities for deepening the specialization of individual workplaces within the enterprise and a high degree of unification of technical and structural parameters of manufactured products.