Economical expediency of aerotechics repair

All details, nodes and aggregates of flight machines depend on resource and may be divided on 4 groups (fig.1.2):

· first group includes details, nodes and aggregates, resource of which is less than service lifetime of flight machine (for example, nodes of aviation engines, landing gear, radio equipment, system aggregates and other equipment), such details, nodes and aggregates, for example, in aircraft about 10-20%;

· second group includes details, lifetime of which is approximately equal to overhaul lifetime of flight machine; these details are repaired more and are seldom replaced on new ones (for example, aggregates of landing gear, hydraulic system and fuel aggregates); this group is 50-60% of all details, nodes and aggregates;

· third group includes details, nodes and aggregates, resource of which is equal to two overhaul lifetimes; such details, nodes and aggregates on flight machine are 20-60%;

· fourth group includes details, nodes and aggregates, resource of which is equal to design durability of flight machine, because they are not repaired during overhauls. These are, for example, some forced elements of aircraft, and such elements are approximately 10%.

Repair of aerotechics should be profitable. One among main requirements during calculation of profitability of repair enterprise is the next inequality:

Ср<Сн, (1.1)

where Ср – price for repair of one unit of flight machine; Сн – price of creation of new flight machine of typical construction.

It is well-known, that the price of repair has two components. To first is drifted the cost of constant works which are not dependent on technical condition of flight machine.

To the second component is drifted the cost of changeable works, which are dependant on technical condition of flight machine, which is repaired. Volume and labour intensiveness of performing repair works with purpose to rehabilitate details, nodes, and aggregates depends on their resources, availability of different defects, which should be repaired.

Fig. 1.1 Flight machine cost changing according to number of repairs and serial production.

Дата добавления: 2014-01-05