Transcript Master Production Scheduling (MPS)

Session 8
Master Production Scheduling (MPS) –
Managing the MPS
http://www.pom.edu/mpc/lectures_in_manufacturing_planning.htm
lecture session 7
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Example Company MPS Records
Handling MPS Lead Time
Incorporating Capacity Constraints
MPS Stability
Managing the MPS
Master Production Scheduler’s Job
Concluding Principles
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Jet Spray Corporation Master
Planning Schedule
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Handling MPS Lead Time
The Spencer Optics Company produces an inexpensive line of
sunglasses. The manufacturing process consists of
assembling two plastic lenses (produced by the firm's plastic
molding department) into a finished frame (purchased from
an outside supplier).
The firm's sales manager has prepared a 10-period sales forecast
for one of the more popular sunglasses (the Classic model).
The forecast is 100 orders per period. Spencer has customer
orders of 110 units, 80 units. 50 units, and 20 units in periods
l , 2, 3, and 4, respectively. The sunglasses are assembled in
batches of 300. Presently, three such batches are scheduled:
one in period 2, one in period 5, and one in period 8.
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Spencer Optics (Continued)
a. Complete the time-phased record.
a. Classic Model
Period
1
2
3
4
Forecast
100 100 100 100
Orders
110 80 50 20
Available
30 230 130 30
Available to Promise
30 150
MPS (Completion)
300
On-hand = 140, MPS lot size = 300
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6
7
8
9 10
100 100 100 100 100 100
230 130 30
300
300
230 130 30
300
300
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Spencer Optics (Continued)
b.
Prepare the MRP record for the assembly of the sunglasses. The
final assembly quantity is 300, lead time is 2 periods, and there’s a
scheduled receipt in period 2. Note that no inventory is shown for
the assembled sunglasses in this record, since it’s accounted for in
the MPS record.
b. Final Assembly - Classic Model
Period
1 2
3 4 5
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Gross requirements
300
300
Scheduled receipts
300
Projected available balance 0 0 0
0 0 0
0
Planned order release
300
300
Q = 300; LT = 2; SS = 0
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0
8 9 10
300
0
0 0
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Incorporating Capacity Constraints
End Product Beginning Inventory Period Forecast Lot size Hours per lot size
A
B
C
60
20
30
10
5
15
30
20
50
30
20
50
a. Prepare the master production schedule for these
items during the next four periods using the Ethan
Allen master production scheduling method.
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Incorporating Capacity Constraints
a.
Capacity=
Hours
40
35
30
25
20
15
10
5
0
Period 1
Period 2
Period 3
C
C
B
Period 4
B
C
A
C
Produce Period 1
Period 2
Period 3
Period 4
A
60/10 = 6 50 / 10 = 5
30 / 10 = 3
B
20/5 = 4
15 / 5 = 3*
25 / 5 = 5*
C
30 / 15 = 2* 55 / 15 = 3.7
85 / 15 = 5.67
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Incorporating Capacity Constraints
(Continued)
b. Should the plant increase or decrease the
capacity of the final assembly line?
The plant should decrease capacity by 10
hours/period because the total units forecast each
period totals 30 units (10 + 5 + 15) and the time
to produce each unit is 1 hour. Therefore, 30
hours of capacity are required each period versus
40 units of available capacity.
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Incorporating Capacity Constraints
(Continued)
c.
Suppose that the master production schedule is
frozen for the next three periods. What specific
impact would the policy have on the firm's
performance?
Freezing the MPS for the next three periods would
not allow the plant to adjust to any radical changes
in demand but it would stabilize plant operations.
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MPS Stability
• Freezing the MPS
• Time Fencing
– Demand Fence
– Planning Fence
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Ethan Allen Firm
Planned Order Approach
Production
Hours
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Period
Managing the MPS
• Overstated MPS
• MPS Performance Measures
• Monitoring the MPS
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MPS Performance Measures
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Mitel’s Master Production Scheduler
Job Description
A.
Identifying Information
Job Title: Master Scheduler
Department/Unit: Planning & Administration
Job Location: Kanata, Ontario
B.
Job Purpose and Mandate
The incumbent of this position is responsible for the day to day
management of the Master Production Schedule, as it relates to
actioning unplanned forecast demand, forecast shortfalls, production
and inventory changes, allowing accurate and up-to-date information
which in turn drives material and capacity requirements and customer
order dating. An advanced level of material planning and manufacturing
process knowledge is required.
C.
Organization Structure
The Master Production Scheduler reports to the Manager, Planning who
reports to the Director, Planning and Administration.
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Mitel’s Master Production Scheduler Job Description
D.
1.
Job Description
Specific Activities and Accountabilities:
Responsible for the creation and continuous update of the
master schedule that satisfies customer demand, maintains
stability in terms of material and capacity requirements and
minimizes RAW. WIP, and Finished Goods inventory levels by:
• Managing day to day increases/decreases to the schedule
through interface with Materials, Manufacturing and Order
Administration.
• Working with Materials to ensure smooth E.C.O. transition
into factory
• Continuously monitor the impact of ''Performance to
Forecast'' on inventory levels for the current month, and
implement any necessary changes to the schedule; i.e. cut
rollover, Increase availability through Fast-Man MRP tool.
Act as a focal point between N.A. Order Administration,
Manufacturing and Distribution to ensure configured system
orders are:
• Scheduled to meet customer cut-over requirements
• Scheduled to meet manufacturing cell capacity.
• Quoted and reviewed with manufacturing, initiating build
and test.
• Free of any discrepancies, with Order Administration
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notified to correct any problems.
Mitel’s Master Production Scheduler Job Description
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Continuously monitor problem inventory, taking advantage of
any conversion opportunities, making recommendations for
scrapping, or potential ''Fire Sale's".
Assess the impact to capacity, inventory levels, purchase order
activity and problem inventory levels that result from any
proposed major change to the master schedule, utilizing the
Fast-Man MRP tool.
2.
Supervisory Responsibilities:
Direct ( ) Indirect ( )
3.
Key relationships (internal and external)
• Internal and external auditors
• Marketing
• Order Administration
• Distribution
• A1l levels of management within Mitel
• Traffic
• Manufacturing
• Materials Planning
• Product Management
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Mitel’s Master Production Scheduler Job Description
E.
Job requirements
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superior product knowledge
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3-4 years progressive experience in materials or production control
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knowledge of internal Mitel processes and procedures
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APIC's Certification a definite asset
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knowledge gained through APIC's Certification
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organizational and planning skills
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secondary education
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high degree of initiative and personal motivation
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personal computer skills
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broad based knowledge of supply/demand process
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MPS – Concluding Principles
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The MPS unit should reflect the company's
approach to the business environment in which it
operates.
The MPS is one part of an MPC system-the
other parts need to be in place as well for a fully
effective MPS activity.
Time-phased MPS records should incorporate
useful features of standard MRP record
processing.
Customer order promising activities must be
closely coupled to the MPS.
Available-to-promise information should be
provided to both the master scheduler and the
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sales department.
MPS – Concluding Principles
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A final assembly schedule (FAS) should be used to
convert an anticipated build schedule (MPS) into an
actual build schedule.
The master production scheduler must keep the sum of
the parts (MPS) equal to the whole (production plan).
The MPS activity must be clearly defined
organizationally.
Stability must be designed into the MPS and managed.
The MPS should be evaluated with a formal
performance measurement system.
The MPS can be usefully considered as a set of firm
planned orders.
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