1.3 SHOP FLOOR CONTROL

 

• No factory is perfect, and a schedule can become invalid at any time because of,

- Machine breakdown

- Sudden material shortage

- Workforce vacancy

- Tool breakage

- etc.

 

• What to do about it,

- Wait and See

- Try to find alternative production plans/parts

- Ask engineering for replan

- Bump other jobs

- ?????

 

 

1.3.1 Shop Floor Scheduling - Priority Scheduling

 

• Instead of scheduling before production (MRP and Capacity planning), a manufacturer may opt to do scheduling on the fly.

 

• Some of these methods include,

- Earliest operation due date - soonest date. This gives time until due, but ignores processing time.

- Order Slack - soonest date minus processing time. This gives the amount of time to play with.

- Shortest operation first - Do the quickest jobs first. This just clears out WIP faster.

 

 

1.3.2 Shop Floor Monitoring

 

• It is important to know what is happening on the factory floor.

 

• To do this we must pay attention to obvious problems like machine operation, and hidden problems such as quality, and production quantities.

 

• Inspection covers a number of areas,

- Inspection of raw materials

- Inspection of manufactured product

- preprocess

- in-process

- post process

- Inspection of production process parameters

- tools

- fixtures

- production machinery

- Verification/calibration

- inspection fixtures

- Inspection gauges

- Inspection machinery