1. DOM 301 : Operations Management Practice
Master Production Schedule
Materials Requirement Planning
Manufacturing Resource Planning
By;
Munyao Mulwa
Dept Management Science

2. Master Production schedule
MPS is the plan that a company develops for production, inventory, staffing, etc.
  Sets the quantity of each end item to be completed in each week over short-range planning horizon.

3. Master Production schedule
A statement of production, not a statement of market demand
MPS takes into account capacity limitations, as well as desires to utilize capacity fully
Stated in product specifications – in part numbers for which bill of material exist
Since it is a build schedule, it must be stated in terms used to determine component part
needs and other requirements; not in monetary or other global unit of measure

4. Master Production schedule
An effective MPS provides
Basis for making customer delivery promises
Utilizing plant capacity effectively
Attaining the firm’s strategic objectives as reflected in the production plan and
Resolving trade-off between manufacturing and marketing

5. Master Production schedule
MPS INPUTS:
Forecast Demand
Production Costs
Inventory Costs
Customer Orders
Inventory Levels
Supply Lot Size
Production Lead
Time capacity

6. Master Production schedule
MPS OUTPUT (production plan):
Amounts to be Produced
Staffing Levels
Quantity Available to Promise
Projected Available Balance

7. What to produce When to produce How much to produce
Firm orders
from known
customers
Forecasts
of demand
from random
Aggregate
production
plan
What to produce
When to produce
How much to
produce
Inventory
record
file
Engineering
design
changes
Bill of
material
file
Master
production
schedule
(MPS)
Material
planning
(MRP)
Reports 12 12 12

8. Structured Approach to Master Scheduling
• Select the items and /or levels in the product structure to be included in the master schedule
• Determine the time horizon and time fences for the master schedule
• Obtain demand information for each item in the schedule over the time horizon
• Prepare tentative master schedule
• Perform rough-cut capacity planning on the tentative master schedule
• Revise the tentative master schedule so it is capacity feasible

9. Time Fences Frozen Moderately Firm Flexible
No schedule changes allowed within this window
Moderately Firm
Specific changes allowed within product groups as long as parts are available
Flexible
Significant variation allowed as long as overall capacity requirements remain at the same levels 9 9 9

10. Forecast and available
Time Fences 8 15 26
Weeks
Frozen
Moderately
Firm
Flexible
Firm Customer Orders
Forecast and available
capacity
Capacity 10 10 10

11. Master Schedule stability
Freezing and time fencing concepts are used for stability
No changes (or changes only after tougher negotiations) incorporated in certain number of recent periods of the schedule in the case of freezing
Frozen period provides a stable target for manufacturing to hit
Time fences specify periods in which various types of changes can be handled
Two common fences are demand fence and planning fence, demand fence is the shorter of the two 9 9 9

12. Examples of MPS MPS using Level Strategy Week 1 2 3 4 5 6 7 8 9 10 11
Week 1 2 3 4 5 6 7 8 9 10 11 12
Forecast 15
Available 25 30 35 40 45 50 20
MPS
On hand 9 9 9

13. Examples of MPS MPS using Chase Strategy Week 1 2 3 4 5 6 7 8 9 10 11
Week 1 2 3 4 5 6 7 8 9 10 11 12
Forecast 15
Available 20
MPS
On hand 9 9 9

14. Material Requirements Planning (MRP)
Material Requirements Planning (MRP) is a computer-based production planning and inventory control system.
It is a material control system that attempts to keep adequate inventory levels to assure that required materials are available when needed
MRP is applicable in situations of multiple items with complex bills of materials (dependent) demand items 9 9 9

15. Objectives of an MRP system
Ensure the availability of materials, components, and products for planned production and for customer delivery,
Maintain the lowest possible level of inventory
Plan manufacturing activities, delivery schedules, and purchasing activities. 9 9 9

16. Product Tree Structure (BOM)
Product Structure Tree for Assembly of Meter A
LT Inventory
A 2week
C 1 week
D 1 week
Safety stock for A, C & D = 20, 30 & 120 respectively
D(1)
C(1)
D(2) A
Level 0
Level 1
Level 2
Demand for meter type A
Week 42 = 200 Meters
Required;
Create a schedule to satisfy demand, stating any assumptions made 4 4 4

17. Manufacturing Resource Planning (MRP II)
Goal 1: Plan and monitor all resources of a manufacturing firm – manufacturing, marketing, finance, engineering etc firm in a closed loop system generating financial figures
Goal 2: Simulate the manufacturing system. Generate what if scenarios 23 23 23

18. Manufacturing Resource Planning (MRP II)
The fundamental manufacturing equation is;
What are we going to make?
What does it take to make it?
What do we have?
What do we have to get?
Using the example of Meter Type A, answer the above questions 23 23 23