Impact of Quick Changeover on SMEs Assembly Line Productivity: An Empirical Study

Thesis Abstract

The widespread adoption of quick changeover practices in small and medium-sized enterprises (SMEs) promises substantial gains in manufacturing flexibility and throughput; however, empirical evidence from SME assembly lines remains limited, with mixed findings regarding productivity gains, changeover time reduction, and downstream operational performance. This study addresses the problem by examining how quick changeover practices influence assembly line productivity in SMEs, considering contingencies such as workforce skills, changeover standardization, and line configuration. The aim is to quantify the relationship between changeover reductions and productivity outcomes, and to identify mediating and moderating factors that affect this relationship. Specifically, the study seeks to (1) measure current changeover times and productivity levels across a representative sample of SMEs, (2) assess the extent of adoption of SMED (Single-Minute Exchange of Die) principles and related standardization activities, (3) evaluate the impact of changeover time on throughput, uptime, and overall equipment effectiveness (OEE), and (4) elucidate organizational and operational conditions that strengthen or weaken the productivity gains from quick changeover. The study adopts a cross-sectional, mixed-methods design combining quantitative and qualitative data to triangulate findings. The population comprises SMEs in the manufacturing sector located in industrial clusters within the region, with production lines implementing varying degrees of quick changeover practices. A stratified random sample of 180 assembly lines from 90 SMEs will be selected to ensure representation by product complexity, automation level, and firm size. Quantitative data will be collected via structured surveys and plant records, complemented by on-site timing studies to capture actual changeover durations, throughput rates, downtime logs, and OEE components. Qualitative data will be gathered through semi-structured interviews with production managers and line supervisors to capture contextual factors, barriers, and best practices. Validity will be enhanced through instrument piloting, triangulation of quantitative and qualitative findings, and member checking for interview transcripts. Reliability will be established with Cronbach’s alpha for multi-item scales and inter-rater reliability for observational timing measurements. Analytical approaches will include descriptive statistics to profile changeover practices, regression analysis to quantify the impact of changeover time reductions on productivity metrics (throughput, uptime, OEE), and multilevel modeling to account for nested data at line and firm levels. Mediation analysis will test whether standardization, worker skills, and changeover team organization transmit effects from changeover reductions to productivity gains. Moderation analysis will examine how automation intensity, product variety, and line layout influence the strength of the relationship. Theoretical grounding will draw on the SMED framework and the Theory of Contingency, supplemented by the Dynamic Capabilities perspective to interpret how SMEs leverage quick changeovers under resource constraints. The expected findings anticipate that substantial reductions in changeover time are positively associated with higher throughput and OEE, with the magnitude of gains moderated by workforce expertise and standardization maturity. Intermediate results may reveal diminishing returns beyond a threshold of changeover simplification in highly automated lines or highly customized product mixes. The study contributes to knowledge by providing robust, SME-specific empirical evidence on the productivity effects of quick changeover, clarifying the conditions under which SMED practices yield measurable gains, and offering a validated analytical framework for practitioners and policymakers. The findings will inform SME managers on targeted investments in standardization, cross-training, and changeover teams, and will guide industry associations and regional development programs in tailoring support for quick changeover adoption. The main conclusion is expected to be that quick changeover enhances assembly line productivity in SMEs when complemented by standardized processes, skilled multifunctional teams, and appropriate line configurations; without these supports, productivity gains may be modest or context-dependent. The study recommends implementing a staged SMED program with metrics-driven milestones, concurrent development of operator skill ladders, and alignment with broader lean manufacturing and digital monitoring initiatives to sustain productivity improvements over time.