Transcript Document

Session 12
System Transactions
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The MRP Planner’s Job
Transaction Example
Key Transactions Concepts
Procedural Inadequacies Example
Complex Transactions Processing
Company Examples
Material Planning: Concluding Principles
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The MRP Planner’s Job
Primary Actions
• Release Orders
• Reschedule Open Order due dates
• Analyze and Update Planning Factors
• Reconcile Errors
• Problem Solving
• Use the system to solve critical material shortages
• Improve the system
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Transaction Example
The MPC system at the Duckworth Manufacturing Company
is run each period to update the master production schedule
(MPS) and MRP records. At the start of period 1, the MPS
for end products A and B is:
Master production schedule
Period Number
1
2
3
4
5
6
Product A
10
-
25
5
10
-
Product B
5
20
-
20
-
20
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Transaction Example: Problem 14
One unit of component C is required to manufacture one unit
of either end product A or B. Purchasing lead time for
component C is two periods. an order quantity of 40 units
is users and no (zero) safety stock is maintained for this
item. Inventory balance for component C is 5 units at the
start of period l, and there's an open order (scheduled
receipt) for 40 units due to be delivered at the beginning
of period l.
a. Complete the MRP record for component C as it would
appear at the beginning of period 1.
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Transaction Example
(Continued: Component C)
a. Period
1
2
3
4
5
6
Gross Requirements
15
20
25
25
10
20
Scheduled Receipts
40
10
25
0
30
10
Projected Available Balance
Planned Order Release
5
30
40
40
Q = 40, LT = 2, SS = 0
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Transaction Example
Problem 14 (Continued)
b.
During period l , the following transactions occurred for component C:
1.
2.
3.
4.
5.
6.
The open order for 40 units due to be received at the start of period
l was received at the start of period 1 with a quantity of 30 ( 10
units of component C were scrapped on this order).
An inventory cycle count during period l revealed that five units of
component C were missing. Thus. an inventory adjustment of -5
was processed.
Ten units of component C were actually disbursed (instead of the l5
units planned for disbursement to produce end products A and B).
(The MPS quantity of 5 in period 1 for product B was canceled due
to a customer order cancellation.)
The MPS quantities for period 7 include 15 units for product A and
0 units for product B.
Due to a change in customer order requirements, marketing has
requested that the MPS quantity of 25 units for product A scheduled
in period 3 be moved to period 2.
An order for 40 units was released.
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Transaction Example
Problem 14 (Continued)
Given this information, complete the MRP record for component C as it would
appear at the beginning of period 2.
What action(s) are required by the inventory planner at the start of period 2 as a
result of transactions occurring during period 1?
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Transaction Example (Continued)
b. Component C
Period
2
3
4
5
6
7
Gross Requirements
45
0
25
10
20
15
30
20
0
25
Scheduled Receipts
Projected Available
Balance
Planned Order Release
40
20*
-25
40
15
40
Q = 40, LT = 2, SS = 0
*20 = 5 (Previous) + 30 (Receipt) - 5 (Adjustment) - 10 (Disbursement)
The inventory planner should “expedite” the scheduled receipt from
period 3 to be delivered in period 2.
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Key Transactions Concepts
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Order Launching
Allocation and Availability Checking
Exception Codes
Bottom-up Replanning
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Procedural Inadequacies Example:
Part A
Consider the MRP record at right
for Cactus Cups.
• 5 units of the scheduled
receipt for 40 units due at the
start of period 2 are scrapped
during period 1.
• No scrap ticket is issued.
• Assume this lot isn’t counted
before it’s put away in the
stockroom at the start of
period 2, but is recorded as a
receipt of 40 units.
What impact will these actions
have on factory operations?
Period
Gross requirements
1
2
3
4
5
6
25
30
5
15
5
10
Scheduled receipts
Projected Available Balance
40
35
10
20
15
15
0
10
0
Planned order releases
Q = lot-for-lot; LT = 5; SS = 0
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Procedural Inadequacies Example:
Part B
• Without recording the scrap, the
MRP record will appear as it
does in the previous slide. If the
scrap had been reported, it
would be:
• The 5 unit shortage may not be
discovered until period 4. At
that time, it will be necessary to
expedite the scheduled receipt
of 15 from period 5 into period
4, and cover the deficiency in
period 6.
Period
Gross requirements
1
2
3
4
5
6
25
30
5
15
5
10
Scheduled receipts
Projected Available Balance
35
35
10
15
15
10
-5
5
Planned order releases
Q = LFL; LT = 5; SS = 0
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-5
MRP Record Relationships for Several Parts
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Example MRP Record
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Jet Spray MRP System Inquiry (part S3273) –
Bucket-Less System
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Jet Spray MRP System Exception Messages (part S3273)
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Concluding Principles
• Effective use of an MRP system allows development of a forwardlooking (planning) approach to managing material flows.
• The MRP system provides a coordinated set of linked product
relationships, thereby permitting decentralized decision making on
individual part numbers.
• A1l decisions made to solve problems must be done within the system,
and transactions must be processed to reflect the resultant changes.
• Effective use of exception messages allows focusing attention on the
"vital few," not on the "trivial many."
• System records must be accurate and reflect the factory's physical
reality if they're to be useful.
• Procedural inadequacies in processing MRP transactions need to be
identified and corrected to ensure material plans are accurate.
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