3. Decisions of supplier selection

3. Decisions of supplier selection depending on parts features
Parts with a high degree of specialization usually can be purchased only from machines manufacturer. Machines
manufacturers often have exclusive rights to distribute certain items, while they purchase parts from their
manufacturers. Installation of this type of element in the machine provides servicing of machine manufacturer and
specified vitality guarantee. In this aspect, selection of provider depends on a contract of guarantee, because
purchasing parts from another supplier than recommended is associated with loss of warranty or resignation of
servicing.
Manufacturers of original parts produce, among other items intended for direct sole sale for machine users or
indirect sale through machine manufacturer, even though purchase of part is not associated with servicing of machine
manufacturer.
Non-original parts are available for machine users without limitation in the third group of supplier, who are
manufacturers of substitutes (ie. substitutes mean parts of a similar structure to the structure of original parts but
different lifetime) and intermediaries. They sell standard (typical) items intended for various industries. Making a
decision concerning this type of suppliers, at the first, buyer takes offered price into account. Hence, selection of
supplier in this area can generate the greatest savings.
An important issue to be considered, due to effective spare parts management is a collective order. In the case of
minor elements whose annual consumption is regular and high, ordering a single units from an economic point of
view is unprofitable. Prices of these parts are usually low, while transport costs disproportionately high. Collective
orders concern items which due to wide area of application and size must be purchased in packs and sets (screws,
fittings). In the case of ordering this type of items, realization of the whole process is lengthened to the point, when