Page 445 - Design of Simple and Robust Process Plants

432 Chapter 10 The Efficient Design and Continuous Improvement of High-quality Process Plants
Timing/documentation: the over-design methodology needs to be documented in a
report as part of the design basis to be prepared at the beginning of the conceptual
design phase.

10.3.2.7 Maintenance
This is an often-overlooked activity at the design of a facility. It is however very
important, as an objective of simple and robust designed plants is to opt for a main-
tenance-free plant. It will be clear that this is a target that we hope to approach, but
even between the turn-around some maintenance might be necessary. Besides that,
plants are subject to modifications during turn-around, so access is required for
modification and maintenance.
The involvement of the maintenance function to a project is required for:
± Equipment selection, equipment monitoring, RAM specifications.
± Plot plan and lay-out development for accessibility of equipment that might
be subject to maintenance or future modifications.
± Development of detailed lay-outs for small equipment, piping items and
instruments for accessibility.
The contribution of the maintenance function should be based on a maintenance
strategy for the plant under design. The strategy should cover the following elements:

± Predictive maintenance. This is focused on equipment monitoring, failure
analysis based on historic data to predict upcoming failures, repair time pre-
dictions (particular important for the ªdesign for single reliable and robust com-
ponents unless¼.º design philosophy).
± Preventive maintenance. This is addressing timely replacement of equip-
ment based on historic life cycle data.
± Breakdown maintenance. This is focused on the replacement of items after
failure in a short time frame.
The maintenance strategy will have elements of different approaches, and must
include repair times, round-the-clock service, spare parts, and contracting mainte-
nance.
Timing/documentation: the maintenance strategy needs to be developed during
basic engineering and used as reference for the project life from basic engineering
up and to the operational phase.

10.3.2.8 Construction
The development of detailed construction plans, from the initial plan up and to the
full-blown construction plan are essential for timely project delivery. The input from
the construction function is required for:

± Plot plan and lay-out development.
± Major equipment dimensioning (field erection versus shop fabricated with
reference to transportation ).
± Project planning.