Business Case
A manufacturer specializing in truck and bus body building was experiencing increasing demand for tipper cabins and SLR bus chassis. However, production capacity was constrained by inefficient material movement, bottleneck operations, and long cycle times across key manufacturing processes.
The goal was to increase production capacity in two critical operations: tipper cabin building and SLR chassis machining, without investing in additional equipment or infrastructure.
Current State Observations
To identify improvement opportunities, our team conducted value stream mapping and prepared material flow diagrams for the two product streams.
- Tipper cabins travelled nearly 2 km within the facility during the manufacturing process to undergo various operations.
- Significant waiting occurred before each process while most assembly activities were carried out directly on the cabin structure.
- In the chassis machining line, drilling operations formed the main bottleneck, with each chassis taking up to 3 hours to machine.
Solution Synopsis
- The production approach for tipper cabin assembly was redesigned so that the cabin remained stationary in a work bay while operator teams moved between bays.
- Sub-assembly stations were introduced for cabin frames and door frames to enable parallel preparation and faster final assembly.
- Masking templates were created to reduce preparation time before painting, and workstation stands improved operator ergonomics during trim fitting.
- For chassis machining, drilling operations were split across two available machines to allow parallel processing.
- Drilling sequences were optimized to reduce unnecessary repositioning of long chassis frames, while quick-change drill bits and improved clamping systems reduced setup time.
Outcomes
Operational improvements significantly increased manufacturing productivity and eliminated unnecessary movement across the shop floor.
Before
- Tipper cabin building required about 11 hours per unit, limiting daily production output.
- Chassis machining operations took up to 3 hours per frame, restricting bus production capacity.
- Extensive movement of cabins across the shopfloor created congestion and inefficient use of space.
After
- Tipper cabin building time reduced from 11 hours to 5.5 hours, doubling productivity.
- Chassis machining output increased threefold, producing one finished frame every hour.
- Eliminating movement of cabins freed plant roads and gangways, improving workplace organization and safety.
