Page 47 - Machinery Component Maintenance

32 Machinery Component Maintenance and Repair

3. Supplementary maintenance manpower is provided by using care-
fully selected local contractors. However, by having a well trained
nucleus of supervisory and maintenance personnel available from
within the company, overall manpower efficiency is kept at a higher
level than normal, thus resulting in lower costs and reduced outage
time. Operators are used where possible during turnarounds which
involve plant shutdown.
4. The travel and living costs for the flexible, rotating group of main-
tenance technicians and planners is a minor cost factor compared to
the more efficient use of personnel and reduced outage time. In
many cases, the technician and central maintenance group are geo-
graphically located near key facilities, since this is where they
spend most of their time.

Discussion of any maintenance concept is incomplete without includ-
ing a method of spare parts control. The goal of an effective spare parts
program is to keep the investment in capital spares to a minimum without
seriously jeopardizing the plant onstream factor, and administering the
spare parts program at the lowest possible cost. Only experience, after an
extended operating period, will determine the adequacy of decisions
made in this regard.
The spare parts program at a multi-plant corporation should most cer-
tainly be administered on a centralized basis. The commonality of equip-
ment makes this a prerequisite for low total spare parts investment. The
same central mechanical engineering organization responsible for moni-
toring field mechanical problems is also responsible for the initial selec-
tion of spare parts and the approval for reordering major spares. Initial
spare selections are based on equipment manufacturer recommendations,
operating experiences, and careful analysis of what is in existence. To
obtain the best possible price, major spare parts are negotiated as part of
the original machinery or equipment purchase.
Central Parts Depot

Specific items not common to other facilities and small, normal spares
are maintained at individual facilities. Certain major components com-
mon to more than one operating facility and some parts showing high
usage are stocked at a centrally located parts depot. This concept allows
for a lower total investment in spares. Since spare parts handling, pack-
aging, and long term storage are so critical and require specialized
knowledge, it is necessary to provide this capability at only one location.
It is possible to ship spare parts from this depot on a 24-hour, seven day a
week basis. Transportation arrangements normally keep the total ship-
ping time to less than eight hours. With most maintenance work per-