FP Lec 3 (Compatibility Mode)
FP Lec 3 (Compatibility Mode)
FP Lec 3 (Compatibility Mode)
INE 425
Lec 3
1
Schedule Design
• Schedule design decisions provide answers to
questions involving how much to produce and
when to produce
• Production quantity decisions are referred to
as lot size decisions
• Determining when to produce is referred to as
production scheduling.
2
Schedule Design
How does a schedule design impact the facility design?
Schedule design decisions impact;
• Machine selection • Number of machines
• Number of shifts • Number of employees
• Space requirements • Storage equipment
• Material handling equipment
• Personnel requirements • Storage policies
• Unit load design • Building size
•And more…
3
Schedule Design
• Schedule design determines
How much to produce lot size decision
When to produce production scheduling
How long production will continue market forecast
Two sources
• Marketing Information
• Process Requirements
4
Marketing Information
• A minimum market information given in table
3.2 is needed. Preferably, information
regarding the dynamic value of demands to be
place on the facility is desired.
5
Marketing Information
• If such information is available, a facilities plan
can be developed for each demand state, and a
facility designed with sufficient flexibility to
meet the yearly fluctuations in product mix.
• By developing facilities plans annually and
noting the alterations to the plan, a facilities
master plan can be established.
• Dynamic layouts can be designed to
accommodate varying product demands .
6
Marketing Information
• Ideally, information of the type shown in table 3.3 would be
provided. If such information is available, a facilities plan can be
developed for each demand state and a facility designed with
sufficient flexibility to meet the yearly fluctuations in product mix.
Table 3.3 Market Analysis Indicating the Stochastic Nature o f Future Requirements
for Facilities Planning
7
Marketing Information
• In addition to the volume, trend, and predictability of
future demands for various products, the qualitative
information listed in Table 3.4 should be obtained
Table 3.4 Valuable Information That Should Be Obtained from Marketing and
Used by a Facilities Planner
8
Marketing Information
• Marketing department provides a research
function that analyzes what the world’s
consumer wants. Some of the information that
marketing provides is:
Selling price
Volume, how many can we sell?
Seasonality, summer or winter product
Replacement parts, older products
• Valuable information that should be obtained
from marketing and used by a facilities planner.
See Table 3.4 9
Process Requirements
• Process design determines the specific equipment types
required to produce the product. Schedule design
determines the number of each equipment type
required to meet the production schedule.
• Specification of process requirements typically occurs in
three phases.
1. Determining the quantity of components that must be
produces, including scrap allowance, in order to meet
the market estimate.
2. Determining equipment requirements for ach operation.
3. Combination of the operation requirements to obtain
overall equipment requirements
10
Scrap Estimation
• The market estimate specifies the annual
volume to be produced for each product. To
produce the required amount of product, the
number of units scheduled through
production must equal the market estimate
plus a scrap estimate.
• Hence, production capacity must be planned
for the production of scrap. Otherwise, when
scrap is produced the market estimate will not
be met.
Scrap Estimation
• Scrap is the material waste generated in the
manufacturing process due to geometric or
quality considerations. For example, scrap due
to geometry is generated when a rectangular
steel plate is used to create circular
components or when rolls of fabric are used
to make shirt.
• Total production= market estimate + scrap
estimate
• Scrap = reject - rework
Scrap Estimation
• How is scrap calculated?
• Let dk :represent the percentage of scrap
produced on the kth operation
• Ok: the desired output of non-defective
product from operation k
• Ik: the production input to operation k.
d1
I1
O1
Scrap Estimation
• Thus, the expected number of units to start
into production for a part having n operations
is
d d d