1. Lecture 13 Production Activity Control
Books
Introduction to Materials Management, Sixth Edition, J. R. Tony Arnold, P.E., CFPIM, CIRM, Fleming College, Emeritus, Stephen N. Chapman, Ph.D., CFPIM, North Carolina State University, Lloyd M. Clive, P.E., CFPIM, Fleming College
Operations Management for Competitive Advantage, 11th Edition, by Chase, Jacobs, and Aquilano, 2005, N.Y.: McGraw-Hill/Irwin.
Operations Management, 11/E, Jay Heizer, Texas Lutheran University, Barry Render, Graduate School of Business, Rollins College, Prentice Hall

2. Objectives Production activity control Gantt chart
Critical ratio scheduling
Finite loading
Scheduling
Assignment method

3. Production Activity Control
PAC in the MPC System
Shop Floor Control
Vendor Scheduling
Production Activity Control Techniques
Basic Data
Gantt Charts
Priority Scheduling
Finite Loading
Process Design Impact on Scheduling
Batch Manufacturing – Work Orders
Repetitive Manufacturing – JIT

4. Production Activity Control in the MPC System

5. Basic Data

6. Routing Data and Operation Setback Chart

7. Gantt Charts _____________________________________________________
The incoming orders at Tom's Sailboard follow different routes through the shop but all orders must stop at each of the three work centers in the plant. The table below shows all tasks for four jobs that arrive over 5 days and need to be scheduled at the company. It is currently November 10 and Tom works a seven-day week.
_____________________________________________________
Arrival Job/WC Processing time (days)
Order date routing WC 1 WC 2 WC 3
(B)iff Nov
(G)riffin Nov
(H)erbie Nov
(K)errie Nov
Assume that the new material for all orders is in stock and that a
first-come/first-served sequencing rule is used at all work centers. All three
work centers are idle as work begins on orders B and G on November 10.

8. Tom’s Sailboard
Construct a Gantt chart depicting the processing and idle times for the three work centers for these four jobs.
Arrival Job/WC Processing time (days)
Order date routing WC 1 WC 2 WC 3
(B)iff Nov
(G)riffin Nov
(H)erbie Nov
(K)errie Nov

9. Tom’s Sailboard
How many days does each job wait in queue for processing at work center 2?
The determination of how long jobs wait at work center 2 is as follows: B and G are processed immediately at work center 2, order K must wait 1 day (11/14) and order H waits 4 days (11/12, 11/13 at WC3) and (11/16 and 11/17 at WC2).

10. Priority Sequencing Rules
First Come, First Served
Shortest Operation Next
Earliest Due Date
Order Slack: (Time Remaining until Due Date – Sum of Remaining Setup and Run Time)
Slack per Operation
Critical Ratio: (Due Date-Now)/(Lead Time Remaining)
________________________________________
Lead Time Remaining includes setup, run, move and queue time for all remaining operations.

11. __________________________
Knox Machine
The jobs below are waiting to be processed at the P&W Grinder at the Knox Machine Company. (There are no other jobs and the machine is empty.)
__________________________
Machine processing Date job arrived Job due
Job time (in days)*__ at this machine date__ A B C D
*Note: This is the final operation for each of these jobs.
___________________________________________________________

12. Knox Machine: Solution
The production manager has heard about three dispatching rules: the Shortest Operation Next Rule, the First-Come/First-Served Rule, and the Earliest Due Date Rule. In what sequence would these jobs be processed at the P&W grinder if each rule was applied?
The shortest operation next rule: B-D-A-C
The first-come, first-served rule: D-A-B-C
The earliest due date rule: C-A-D-B
Machine processing Date job arrived Job due
Job time (in days)*__ at this machine date__ A B C D
*Note: This is the final operation for each of these jobs.

13. Knox Machine: Solution
If it's now the morning of July 10 and the Shortest Operation Next Rule is used, when would each of the four jobs start and be completed on the P&W grinder? (Express your schedule in terms of the calendar dates involved, assuming that there are 7 working days each week.)
P & W Grinder
Job B D A C
Date
7/10
7/11
7/12
7/13
7/14
7/15
7/16
7/17
7/18
7/19
7/20
7/21

14. Critical Ratio Scheduling
Eight weeks remain for constructing the a 50­foot yacht. Assume that each week consists of 5 work days, for a total lead time of 40 days. The work required to complete the yacht comprises 10 operations, 4 days for each.

15. Yacht Project Example
On Tuesday morning of week 3, 3 of the 10 operations had been completed and the yacht was waiting for the fourth operation. What's the critical ratio priority?

16. Yacht Project Example
What's the critical ratio priority if only 2 of the 10 operations are completed by Tuesday morning of week 3?

17. Finite Loading

18. The Bundy Company
The Bundy Company produces for three products (A, K, and P). Each order goes through the same three machine centers, but not necessarily in the same sequence. Each order must be finished at a machine center before another can be started. Orders cannot be split. The shop works a single eight-hour shift five days per week. Assume that the time to move between machines is negligible. each machine center is operated eight hours per day. All three machines are currently available for scheduling, and no further orders will arrive.

19. The Bundy Company Processing time Machine at machine center
center ___(in days)____ Order
Order routing due date A K P
Note: Order due dates are fixed based on the shop calendar. It is now 8:00 A.M. Monday (day 1), Monday of next week is day 6, etc.

20. The Bundy Company
Using the horizontal loading procedure with earliest-due-date priority sequencing rule, prepare a Gantt chart showing the production schedule for the three orders above.

21. The Bundy Company
Using the vertical loading procedure and the shortest-operation-next priority sequencing rule, prepare a Gantt chart showing the production schedule for the three orders above.

22. Process Design Impact Scheduling
Batch Manufacturing: Work Orders
Repetitive Manufacturing: JIT/Kanban

23. Scheduling

24. What is Scheduling? Last stage of planning before production occurs
Specifies when labor, equipment, and facilities are needed to produce a product or provide a service

25. Scheduled Operations Batch Production Process Industry
Aggregate planning
Master scheduling
Material requirements planning (MRP)
Capacity requirements planning (CRP)
Process Industry
Linear programming
EOQ with non-instantaneous replenishment
Mass Production
Assembly line balancing
Project
Project -scheduling techniques (PERT, CPM)

26. Objectives in Scheduling
Meet customer due dates
Minimize job lateness
Minimize response time
Minimize completion time
Minimize time in the system
Minimize overtime
Maximize machine or labor utilization
Minimize idle time
Minimize work-in-process inventory

27. Shop Floor Control (SFC)
Schedule and monitor day-to-day job shop production
Also called production control and production activity control (PAC)
Performed by production control department
Loading - check availability of material, machines, and labor
Sequencing - release work orders to shop and issue dispatch lists for individual machines
Monitoring - maintain progress reports on each job until it is complete

28. Loading Process of assigning work to limited resources
Perform work with most efficient resources
Use assignment method of linear programming to determine allocation

29. Assignment Method Perform row reductions Perform column reductions
subtract minimum value in each row from all other row values
Perform column reductions
subtract minimum value in each column from all other column values
Cross out all zeros in matrix
use minimum number of horizontal and vertical lines
If number of lines equals number of rows in matrix, then optimum solution has been found. Make assignments where zeros appear
Else modify matrix:
subtract minimum uncrossed value from all uncrossed values
add it to all cells where two lines intersect
other values in matrix remain unchanged
Repeat steps 3 and 4 until optimum solution is reached

30. Assignment Method Initial PROJECT Matrix 1 2 3 4 Bryan 10 5 6 10
Kari
Noah
Chris
Row reduction Column reduction Cover all zeros
Number lines  number of rows so modify matrix 12

31. Assignment Method Modify matrix Cover all zeros 1 0 1 2 1 0 1 2
Number of lines = number of rows so at optimal solution
Bryan
Kari
Noah
Chris
PROJECT
Bryan
Kari
Noah
Chris
Project Cost = ( ) X $100 = $2,100 12

32. Assignment Method - Setup
Solution goes here Only 1 leader can be assigned to each project
Click “Solve” for solution
Sum of all rows and columns = 1

33. Assignment Method - Solution
Assignments indicated by 1
Cost of solution

34. End of Lecture 13