Page 285 - Improving Machinery Reliability

256 Improving Machinery Reliability

The most recent studies reveal that about a third of the field process operators’
shift time is unstructured and available for tasks other than attending to the
processes.
Reliability-oriented repairs. There have been successes in improving reliability
through corrective actions proposed on a regular basis as part of routine mainte-
nance repair work. The mechanism depends on solid technical knowledge in the
craftsmen and supervisors in the routine maintenance corps and a readily available
maintenance engineering group for support as required. The aim is to make most
repairs permanent if feasible. The results of such a process in one particularly suc-
cessful refinery have eliminated recurring failures to an extent that far less repair
maintenance is required than in most refineries, and the routine maintenance costs
are among the lowest in the world.
The crew concept-a future solution for productivity? Several refineries in the
world have decided to staff their facilities with a cadre of workers capable of both
operating and maintaining the equipment. This type of craftsman-operator has typ-
ically been developed by hiring persons with technical or craft skills and training
them to operate the processing units. Proficiency in maintenance and in operation
is established and maintained by a system of rotation, and multi-craft skill devel-
opment is stressed. The refineries are willing to invest significantly in the develop-
ment of such persons. One such refiner has measured an average of over two main-
tenance skill levels per person in addition to the operator skills. The efficiency and
effectiveness afforded by their success is reflected in the significant fact that they
pay their crew 35% more than other refiners in the region, yet their total mainte-
nance outlay is 25% less than the next best refinery. There are several other signif-
icant rewards:
The crews carry out all preventive maintenance and condition monitoring
schedules while on operating shift assignment.
Rather than assigning two persons to a maintenance job, those assigned to day-
shift process operations are scheduled to provide short-term assistance.
The crew on operating shift performs all preparations for equipment scheduled
for maintenance, including purging and draining, disassembly, and electrical lock-
out and disconnection.
This versatility has enabled those using the dual-function crew concept to record
up to 12% of the refinery’s total maintenance demand and reliability improvement
as being satisfied by the crew members while on operating assignment. This
approach to effectiveness cannot be universal. The attitudes of both the workforce
and management must be synchronized to the same standards of expectations, per-
formance, and job enjoyment. But it may be possible for more refineries to
approach crew benefits if existing work-rule demarcations can be relaxed or modi-
fied. Solomon Associates has observed a more willing acceptance for efficiency
improvement in the younger workers. They appear willing to have a try at learning
more than one skill, but may be confused by attitudes of their first-line supervisors
who matured in a single-skill era and may be unwittingly holding on to concepts
that do not support development of versatility.