Abstract:
Risk-based approach in spare part inventory management and plant maintenance is
essential for ensuring asset integrity in a process facility. The sugar industry in Kenya has
been a victim of inefficient spare part inventory management resulting to unscheduled
factory stoppages, factory breakdowns, obsolescence of plant and equipment whose
maintenance costs are very high. This has been compounded by high maintenance costs
and expensive spares which are also difficult to find and procure. In this regard the
purpose of the current study was to develop a risk based approach to spare part inventory
management in order to improve the performance of the sugar factories. The study sought
to achieve the following objectives: To identify the risk due to unavailability of spare part
in the sugar factory, to asses spare part criticality using fault mode and effect analysis
(FMEA) in the sugar factory and to determine spare part inventory risk mitigation
strategies to be used in the sugar factory. In order to achieve the objectives the study
employed a case study research design. This study targeted spare parts inventory records
and plant maintenance records inventoried for the past one year in Chemelil Sugar
Company. Document analysis was employed as the main tools for collecting secondary
data. Data was analyzed by use of descriptive statistic using Excel. From the Pareto
analysis of boiler, pre mills, mills and juice treatment downtime was used as a spare part
risk identification technique. It was established that boiler, pre mills, mills and juice
treatment had a downtime of 315.51 hrs, 294.19 hrs, 111.13hrs and 82.3 hrs respectively.
Besides that, spare parts failure frequency ranging from 2 to 756 times a year was also
used to identify spare part risk. Critical spare parts were the motors, water pump and the
gears with a criticality index ranging between 8 to 25 based on downtime, lead time and
availability in the market. The study established Reorder points (24, 16, 75), Lead time
demand (13,4,30) and Safety stock (12,13,45) for motors, water pump and the gears
respectively to determine the risk mitigation strategies for the critical spare parts for
Chemelil sugar factory. In conclusion the factory should evaluate their spare parts
inventory critically owing to their effect on the downtime and implementation of risk
based approach to spare part inventory management. The findings of this study widens
interest in the use of Risk based approach to a number of other stakeholders including
operators, maintenance personnel, regulators and insurance companies and other
industries to potentiate plant availability.