Scheduling Page 1
Scheduling in
Repetitive
Manufacturing
Prepared by: Dr. Don Maes
Mascidon LLC
November 2012
Scheduling Page 2
Contents Scheduling ..................................................................................................................................................... 3
Figure 1.1 Production Scheduling Screen ................................................................................................. 4
Figure 1.2 Selective Production Scheduling Screen .................................................................................. 6
Figure 1.3 Item Detail Demand Screen ..................................................................................................... 6
Figure 1.5 Add an Item to the Schedule ................................................................................................... 7
Scheduling Page 3
Scheduling
Scheduling from within SAP flows from the MRP calculations. The ‘Order Recommendations’ file /
report provides the means for reviewing the requirements. In an environment where recommendations
are turned into production orders (PDOs) and these PDO’s are distributed to the floor, this works well.
Let’s assume that individual production orders for the floor are not required. A supervisor manages the
schedule by telling the personnel in his or her department how many to make and what operations to
work on. After creating the schedule, the supervisor can print a copy of the schedule and post it in their
department. The operators would then begin their assignments. This eliminates the need to produce a
piece of paper (PDO) for each production requirement. This schedule is in turn linked to the production
entry from the shop floor. Conceptually, the MRP recommendations have not been eliminated. The
means of presentation and usage of the information has changed.
Mascidon has altered this process by adding the flexibility to create the schedule from open sales, the
MRP recommendations, or Both of these. From an operations view, you must make certain you are not
double dipping – getting the same requirements from MRP and Sales Orders.
The scheduling is based on the requirements for fulfilling sales orders for specific due dates. Each
evening the schedules for open sales orders are recalculated based on the current date and all sales
orders due within the next x days (x is set once and used each evening. The default is 10 days.). This
information is stored in a temporary file that is then used to do the actual scheduling of production. The
production supervisor utilizes the screen shown in Figure 1.1 to begin the daily scheduling process. As
the scheduling screen is accessed, the grid of items is displayed.
The operators cannot access the ‘Scheduling’ screens. This is a supervisor process that must be done on
a daily basis. It can be modified during the day to account for schedule changes. Essentially, the
supervisor looks over the schedule generated by the system and creates a daily manufacturing schedule.
In some instances this may be a weekly schedule. For instance, in shops where coil stamping is used the
machine setups may take several hours to a day. Machine runs typically would be for several days.
Let’s review the scheduling function in depth. When the screen is initially displayed it shows all items
that have requirements but are not currently scheduled. On the screen, the ‘All Items’ would be
checked, the ‘Scheduled Items’ unchecked, and the number of days defaulted to 10.
Scheduling Page 4
Figure 1.1 Production Scheduling Screen
The screen has 3 check boxes and 3 radial buttons that selectively show scheduling data. The usage of
the check boxes and radial buttons are as follows:
1. Scheduled items check box is checked – when this is checked, only items already scheduled by
the production supervisor are displayed. The schedule for all departments is shown unless the
specific department is entered. This is the same information as would be displayed if the
‘Schedule’ report button were clicked and the schedule report is run. Depending on the radial
button settings, portions of the schedule will be presented:
a. All – if this radial button is activated then all items flagged by the production supervisor
as scheduled would be shown.
b. Not Reported – some items within the schedule may be ‘phantom’ parts. Yes, they need
to be produced and the production supervisor needs to inform the floor of the need to
produce these items, but the reported completion of these items will not be entered
into SAP B1 because they are phantom parts. In this instance, only items in the schedule
with the Phantom Flag in the item master set to Yes will be displayed in the schedule.
From a manufacturing reporting view, these could be reported, but would not update
inventory.
c. Reported – items within the schedule that are not ‘phantom’ parts need to be produced
and the production supervisor needs to inform the floor of the need to produce these
items. In this instance, only items in the schedule with the Phantom Flag not set will be
displayed in the schedule.
2. Scheduled items check box is NOT checked – when this is not checked, only items not scheduled
by the production supervisor are displayed. Depending on the radial button settings, portions of
the items not scheduled will be presented:
a. All – if this radial button is activated then all items not scheduled by the production
supervisor would be shown.
Scheduling Page 5
b. Not Reported – some items may be ‘phantom’ parts. Yes, they need to be produced and
the production supervisor needs to inform the floor of the need to produce these items,
but the reported completion of these items will not be entered into SAP B1 because
they are phantom parts. In this instance, only items not in the schedule and phantom
flag set to yes will be displayed.
c. Reported – items not scheduled that are not ‘phantom’ parts need to be produced and
the production supervisor needs to inform the floor of the need to produce these items.
In this instance, only items not scheduled and with phantom flag not set will be
displayed.
3. Select all check box is checked – this flags all the items currently on the screen with the check
box.
Referring back to Figure 1.1, assuming the production supervisor is creating a schedule, then the check
box for the ‘Scheduled Items’ would not be checked. Items would be displayed on the screen. The
supervisor would schedule a part by:
• Entering the quantity to make
• Selecting the operator to assign to making the parts
• Clicking the ‘Select’ check box in the grid portion of the screen (not the ‘Select All’ button).
After performing this operation on as many items as required, clicking the ‘Process’ button moves the
checked items to the ‘Schedule’. This process can be repeated as many times as necessary to create a
full production schedule. At any time, the user can click on the ‘Scheduled Items’ check box and refresh
the screen to see the current schedule. Alternatively, the ‘Schedule’ button can be clicked to print a
report of the scheduled items.
The ‘# of days’ field defaults to 10 days. If the user wants to see the requirements for a shorter period
of time so that immediate demand can be scheduled first, then this number can be changed. The items
on display may change (some items may not be required for the first 5 days for example), and the
quantity required will change. The Details behind the schedule will still show total demand so the
scheduling person can make a determination of how many to run if they are setting up the tooling /
machine to run anyway.
With a large data file it is difficult to manage entries to the schedule. The ‘Item’ field entry under the ‘#
of days’ label provides for a shortening of the list of items to manage at any time.
The user can change the sort sequence of the information by clicking on the column header to sort.
Clicking on the same column header a second time reverses the sort sequence for that column.
Scheduling Page 6
Figure 1.2 Selective Production Scheduling Screen
During the creation of the schedule, the user may look at a requirement for an item and want to know
what created demand for a specific item. To obtain this information the user would double click on a
field within the schedule. The item details screen as shown in Figure 1.3 is displayed. The example
shows the source of the demand – in this instance Sales Orders. The MRP Forecast could be a second
source. If any items are currently produced, then the total quantity already produced will be displayed.
Figure 1.3 Item Detail Demand Screen
With the ‘Scheduled Items’ check box checked, the screen shows the schedule. The scheduling person
enters the quantity to make for any item and assigns the work to an operator. As they select a
particular item to produce, that line is highlighted so that scheduled items are easy to identify. To print
a report of the schedule, click on the ‘Schedule’ button. The report is shown in Figure1.4.
Scheduling Page 7
Figure 1.4 Scheduled Items Shown On Screen
This report has a page break based on the date and the operator. This is done for convenience so the
production scheduling person can hand out the assignments. The blue, italicized item is an indication
that the production for this item needs to be entered into SAP.
If a row that is scheduled (see settings for check boxes and radial buttons) is highlighted and then the
‘Remove Row’ button is clicked, then the item in that row is removed from the schedule.
The ‘Add Item’ button on the screen provides a means to add an item to the schedule that may not be in
current demand. This provides the ability to schedule a production run to use a coil of steel (for
instance) in its entirety to produce some items that will have demand in the near future or can be used
as components for multiple popular parts. Clicking on the ‘Add Item’ button presents the screen shown
in Figure 1.5. The scheduling person enters the item, quantity and operator to assign and clicks the ‘Add
Item’ button. This item is then added to the schedule.
Figure 1.5 Add an Item to the Schedule
The schedule produced by entering quantity – operator information remains in the schedule file across
multiple days. This is intentional. It is done so that items that are scheduled once per week can be
intermingled with the schedule for items scheduled every day. It is likely, but not mandatory, that a
Scheduling Page 8
single operator will have a schedule for a single date. Remember, the overall demand is recalculated
each evening and stored in a file. As the scheduling is revisited each day, the user can review previously
scheduled production or clear out the prior information. To clear out prior date information, enter the
From and To Dates on the bottom corner of the screen and click the Clear Schedule button. To clear the
entire schedule use a from – to date range that would cover any information in the schedule file.