Quality Control
Quality control= the stabilization and maintenance of a transformation process to produce consistent output
Crocs production process:
Raw materials (chemicals) purchased in pellet form
Compounding
Add color dyes
Injection molding (requires injection molding machines and molds for each style and size)
Assembled (may involve gluing or stitching if using leather, canvas or materials)
Tagged and place into boxes
Quality Control System
Inspections take place at critical points:
1. Before production (raw materials)
2. During production
-Process quality control takes place, which involves statistical process control. Periodic samples are taken from a continuous production, as long as sample measurements fall within the control limit the production will continue. However, if the samples fall outside the control limits, the process is stopped and a search is made for an assignable cause. In this case, the process will use a quality control chart known as an attribute control chart. The whole purpose is to find the natural random variability in the output oppose to unnecessary variations. The company must maintain that natural random variability to be under statistical control
3. After production
Process Capability
Process capability is assessed once the process is under statistical control. It is the ability of the process to meet or exceed customers' specifications. Process capability is determined by using the process capability index.
Continuous Improvement
Through the process capability assessment, the company can determine which processes should be improved in which case they would use several tools. The seven tools include:
Flow chart
Check sheet
Histogram
Pareto Chart
Cause & effect
Scatter diagram
Control chart
The tools make it possible to reduce defects and improve quality, but they also have to be incorporated into an improvement approach. This would be Six Sigma:
1. Define: a process is selected for improvement and a cross-functional team is form
2. Measure- with the use of measures that are critical to the customer, the team begins improvement by flowcharting the process and defining process defects
3. Analyze- the team seeks the root causes of the current identified and alternatives are considered
4. Improve- improvements are made
5. Control - a control plan is put in place to ensure that changes are permanent