Now almost always the raw materials are complex. Use of complex raw materials usually leads at its preprocessing to development of a number of parallel production chains. Besides, also other phenomenon – development of uniform types of raw materials and receiving from these types of raw materials of related ready-made products in practice is widely known at proximity of technological processes of their production. Nature of productions is defined also by a look and quantity (on a unit of production) the used energy.
At the following step of classification each of the called sequences of productions – the woodworking and wood processing – is considered as under cycles. For each of them the set of sequences of processes is characteristic. Woodworking under a cycle unites only such processes which are connected with mechanical impact on wood: sawmilling, housing construction, shipbuilding, shlapopileniye, etc. The special place is taken by production of plywood which is used in all productions of standard houses, vessels, furniture as a semi-finished product. To woodworking under a cycle also the processes serving a woodworking cycle belong.
N. N. Kolosovsky planned eight generalized cycles (or their sets): a pyrometallurgical cycle of ferrous metals, petropower chemical, set of hydropower industrial cycles, set of cycles of the overworking industry, a lesoenergetichesky cycle, set of industrial and agrarian cycles and a hydromeliorative industrial and agrarian cycle (for areas of the irrigated land tenure). Besides, it planned the ninth cycle – atomic energy – as
These principles of classification can be considered on the example of a lesoenergetichesky cycle. For a generalized lesoenergetichesky cycle initial raw materials – wood – is complex raw materials. The generalized lesoenergetichesky cycle unites such productions, as machining and chemical processing of wood, in the technological relation the essentially various. But both types of processes are characterized by approximately identical level of consumption of work and energy.
Division woodworking and wood processing under cycles happens after implementation of such production stages, as logging and a buck of wood. Thus, the first stages, and also forestry as a certain production stage of preparation of forest resources for the cabin for two under cycles the general. Works on reforestation will be the general, naturally, also.
Wood processing under a cycle unites production of sulphatic, sulphitic, natronny cellulose, paper, a cardboard, viscose and viscose fabrics, and also all productions serving on waste and all productions serving wood processing under a cycle.
The same products can be received at the enterprises of various cycles. For example, alcohol is made from agricultural products, wood waste, at chemical oil refining. In the first case its production joins in an industrial-agrarian cycle (in the detailed analysis in one of branches), in the second – in lesoenergetichesky, in the third – petropower chemical. Other example: production of sulfuric acid, as a rule, joins in a cycle of an igneous metallurgy of non-ferrous metals. But at a certain combination of productions it can be included and in other cycles. For example, in the economic region at sulphitic processing of wood vitriolic production can be created for the needs. In this case construction of vitriolic plant was defined by requirements of a lesoenergetichesky cycle which structure will include this plant as production of services. At classification of cycles also more complex problems meet. For example, in the analysis of set of industrial and agrarian cycles it is possible to see that the same branches of a cycle repeat several times. But at classification of cycles (as, however, and in all other scientific researches) it is necessary to be based on reality, but not to go way of formal logic.
These three circumstances give the chance to make a certain synthesis of processes, i.e. generalization of power production cycles, and to construct their hierarchy. On the specified bases in the classification offered below three steps are allocated: generalized cycles and generalized set of cycles; under cycles; branches of cycles.