dc.description.abstract |
Spinning mills in Kenya are operated by eight integrated textile industries to produce
cotton yarns for internal use by their knitting and weaving departments and for sale to the
local market. Fabric requirement estimated at 225 million square meters cannot be
supplied by local domestic production and the gap is met through importation of fabrics
and finished garments. Spinning mills play a very significant role in backward integration
of the textile value chain by converting fibres into yarn for fabric production. Ring
spinning is the most widely used cotton short staple spinning system to produce yarn
from cotton fibers and is used by 7 of the 8 spinning mills. In Kenya, spinning mills have
been operating at spindle utilisation between 67 to 80% which is below the recommended
standard norm of 98%. The mills have been experiencing yarn production loss occurring
from frequent stoppages of the ring frame and increase in the number of spindles running
without producing yarn reducing the ring frame spindle hours used for yarn production.
The overall objective of this study was to improve ring frame spindle utilisation in terms
of spindle hours utilized for yarn production in cotton short staple spinning, a case study
of Sunflag Textile and Knitwear Ltd. The specific objectives were to analyze ring
spinning process production parameters, evaluate the factors affecting ring frame spindle
utilisation and formulate a productivity improvement method for the mill.
The Research design adopted by this study was a descriptive and quantitative case study.
Pareto analysis was used to classify ring frame production losses based on Overall
Equipment Effectiveness (OEE) classification of major losses and Ishikawa diagram used
to carry out Root Cause Analysis of main causes of production loss. Failure Mode and
Effects Analysis (FMEA) technique was used to map the failures which occurred within
the process that contributed to production loss which were ranked using their Risk
Priority Numbers (RPN). A questionnaire based on Grunberg Performance Improvement
Method (PIM) was used to analyse and evaluate mill production and management
practices. A production improvement method was recommended using 7 evaluation
criteria of the PIM. Pareto analysis revealed that Idling and minor stoppages accounted
for 63% losses while breakdown accounted for 22.8% of losses. Root Cause Analysis
(RCA) identified Manual doffing, lack of time awareness, and delay in replacement of
empty bobbins as significant factors that affected ring frame doffing stoppage loss. It was
recommended that a standardized procedure Single Minute Exchange of a Die (SMED)
technique for the doffing procedure would yield the highest results in minimizing ring
frame stoppage. A key finding from the study showed that utilisation of equipment for
production in manufacturing was not just the overall time the machine was running, but
about standardization of the entire process of production to maximize utilization of the
machine for output. Through this study, spinning mills in Kenya can apply the
recommendations to improve ring frame productivity in order to reduce the cost of
production and improve their competitiveness. |
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