Scheduling Multiple Work Centers with Different Standard Hours

Confusion may arise after a work order is scheduled. It may appear that the scheduling process used an incorrect number of available hours when the work center from a previous step has a different number of standard hours than the work center indicated on the current step (for example, if Work Center A works 10 standard hours per day and Work Center B works 8 standard hours per day). A user may incorrectly assume that when starting a new step, hours left over from the previous step are available for the new step.

When scheduling a work order, the arrival time of a work center is taken into consideration. It is assumed that all work centers start work at the same time; therefore, the available hours for the next work center are adjusted to ensure that a work order is not transferred to a work center that is closed for the day.

Multiple Work Centers Backward Scheduling Example 1

In this example, the following data is used.

Work Center 1 works 10 hours a day, Monday through Friday.

Work Center 2 works 8 hours a day, Monday through Friday.

The work day for both work centers is assumed to start at 9 AM (no actual start time can be entered).

No weekends or holidays are included.

In this example, the work order's due date is 05/30/03. There are two steps involved in completing the work order: Step 0000 and Step 0010. Work Center A is assigned to Step 0000 and Work Center B is assigned to Step 0010. Work Center A needs 10 hours to complete Step 0000. After Work Center A completes Step 0000, Work Center B needs 10 hours to complete Step 0010. The table below illustrates how the work order is scheduled using backward scheduling.

Work Center

5/26/03

5/27/03

5/28/03

5/29/03

5/30/03

Step 0000:
Work Center A needs a total of 10 hours to complete this step

10 hours are available

10 hours are available
(4 hours are scheduled)

3 pm – 7pm

10 hours are available
(4 hours are scheduled)
9 am – 3 pm

10 hours are available

Step 0010:
Work Center B needs a total of 10 hours to complete this step

8 hours are available

8 hours are available
(2 hours are scheduled)
3pm – 5pm

8 hours are available
(2 hours are scheduled)
9 am – 5 pm

When scheduling backwards, Work Center B schedules 8 hours for Step 0010 on 05/30/03 and schedules the remaining 2 hours on 05/29/03. Because only 2 hours are scheduled on 05/29/03 for processing Step 0010, Work Center B must receive the parts from Work Center A by 3 pm or Work Center B will not be able to fit in two hours of work by the end of their workday (5pm).

Because Work Center A must complete Step 0000 by 3pm on 05/29/03, Work Center A only has 6 hours available on 05/29/03 to process Step 0000. As a result, the remaining 4 hours required to complete Step 0000 are scheduled on 05/28/03.

Multiple Work Centers Backward Scheduling Example 2

In this example, the following data is used.

Work Center 1 works 10 hours a day, Monday through Friday.

Work Center 2 works 8 hours a day, Monday through Friday.

The work day for both work centers is assumed to start at 9 AM (no actual start time can be entered).

No weekends or holidays are included.

In this example, the work order's due date is 05/30/03. There are two steps involved in completing the work order: Step 0000 and Step 0010. Work Center B is assigned to the first step, Step 0000, and Work Center A is assigned to the second step, Step 0010. Work Center B needs 10 hours to complete Step 0000 and Work Center A needs 10 hours to complete Step 0010. The table below illustrates how the work order would be scheduled using backward scheduling.

Work Center

5/26/03

5/27/03

5/28/03

5/29/03

5/30/03

Step 0000:
Work Center B needs a total of 10 hours to complete this step

8 hours are available

8 hours are available
(2 hours are scheduled)

3pm – 5pm

8 hours are available
(8 hours are scheduled)
9 am – 5 pm

8 hours are available

Step 0010:
Work Center A needs a total of 10 hours to complete this step

10 hours are available

10 hours are available
(10 hours are scheduled)
9am – 7pm

When scheduling backwards, Work Center A has 10 hours available so Step 0010 can be completed in one day on 05/30/03. Work Center B works 8 hours per day; therefore, it takes two days to complete Step 0000 (a 10 hour task). Work Center B must start the step by 05/28/03 at 3 pm.

Multiple Work Centers Forward Scheduling Example 1

In this example, the following data is used.

Work Center 1 works 10 hours a day, Monday through Friday.

Work Center 2 works 8 hours a day, Monday through Friday.

The work day for both work centers is assumed to start at 9 AM (no actual start time can be entered).

No weekends or holidays are included.

In this example, the work order's release date is 05/30/03. There are two steps involved in completing the work order: Step 0000 and Step 0010. Work Center A is assigned to the first step, Step 0000, and Work Center B is assigned to the second step, Step 0010. Work Center A needs 10 hours to complete Step 0000 and Work Center B needs 10 hours to complete Step 0010. The table below illustrates how the work order is scheduled using forward scheduling.

Work Center

5/26/03

5/27/03

5/28/03

5/29/03

5/30/03

Step 0000:
Work Center A needs a total of 10 hours to complete this step

10 hours are available

10 hours are available
(10 hours are scheduled)

9 am – 7 pm

10 hours are available
(8 hours are scheduled)

10 hours are available

Step 0010:

Work Center B needs 10 hours to complete this step

8 hours are available

8 hours are available
(8 hours are scheduled)
9 am – 5 pm

8 hours are available
(2 hours are scheduled)
9 am – 11 am

When scheduling forward, Work Center A can complete Step 0000 in one day on 05/28/03. Work Center B schedules 8 hours on 05/29/03 at 9 am. The remaining 2 hours required to complete Step 0010 are scheduled on 05/30/03 from 9 am to 11 am.

Multiple Work Centers Forward Scheduling Example 2

In this example, the following data is used.

Work Center 1 works 10 hours a day, Monday through Friday.

Work Center 2 works 8 hours a day, Monday through Friday.

The work day for both work centers is assumed to start at 9 AM (no actual start time can be entered).

No weekends or holidays are included.

In this example, the work order's release date is 05/30/03. There are two steps involved in completing the work order: Step 0000 and Step 0010. Work Center B is assigned to the first step, Step 0000, and Work Center A is assigned to the second step, Step 0010. Work Center B needs 10 hours to complete Step 0000 and Work Center A needs 10 hours to complete Step 0010. The table below illustrates how the work order would be scheduled using backward scheduling.

Work Center

5/26/03

5/27/03

5/28/03

5/29/03

5/30/03

Step 0000:
Work Center A needs a total of 10 hours to complete this step

8 hours are available

8 hours are available
(8 hours are scheduled)

9 am –5 pm

8 hours are available
(2 hours are scheduled)
9 am – 11 am

8 hours are available

Step 0010:
Work Center A needs 10 hours to complete this step

10 hours are available

10 hours are available
(8 hours are scheduled)
11 am – 7 pm

10 hours are available
(10 hours are scheduled)
9am – 11am

When scheduling forward, Work Center B works 8 hours per day with 8 hours scheduled on 05/28/03 and two hours pushed to 05/29/03. Because the assumption is that work centers start their workday at 9 am, Step 0000 would not be completed until 11 am on 05/29/03.

Work Center A starts Step 0010 at 11 am. Working 10 hours per day, Work Center A schedules 8 hours on 05/29/03. The remaining 2 hours required to complete Step 0010 are scheduled on 05/30/03 from 9 am to 11 am.

For more information, see:

Work Center Maintenance