In this PPT, a Detailed view on Production scheduling is discussed.

1. PRODUCTION
SCHEDULING
Unit-4

2. Production Scheduling
• Production Control has the controlling
Mechanism, tries to take corrective action to
match the planned and actual production.
Thus production control review the progress
of the work, takes and corrective step in order
to ensure that programmed production takes
place.

3. Functions of Production Control and
Scheduling
Release Order – to the system
Assign Work – to work Centers
Sequencing priority Jobs
Control – the manufac. Lead Time
Monitor Priority Status
Monitor Capacity Status
Six Key
Functio
ns

4. Production Scheduling & Control Function

5. Machine Loading
• Loading is also Known as Machine loading,
may be defined as the assignment of work to a
facility ( facility may be machine, group of
men, entire plan, etc.,) without specifying
when the work is to be done and in what
sequence.

6. Loading Chart

7. Loading
Loading Provides:
• An information to ensure the efficient
utilization of the plant and labor in a factory:
• An Information to help in setting of reliable
delivery.
• An information to assist in forward planning of
purchase of the new plant.

8. Objective of Loading
• To Check the feasibility of production
programmes.
• To assist in the efficient planning of new work.
• To assist in balancing the plant to the existing
load.
• To assist in fixing of reliable delivery promises.

9. PRODUCTION CONTROL

10. Production Scheduling
• A Production Scheduling is like a timetable
that tells us what machine or department
should be doing what and when.
• The production schedule should be
formulated for the method which satisfactorily
match the system requirement with the
available resources.

11. Scheduling
• Scheduling refers to the setting of operation
start dates so that jobs will be completed by
their due date.
• In broader sense scheduling establishes the
timing of productive activities that use the
firm’s human and equipment resources to
serve its customers.

12. Scheduling
• The various function an effective production
scheduling system included:
• Allocating Jobs to facilities.
• Establishing a set of rules of priorities to
sequences the activities on the facilities.
• Dispatching job orders as per the scheduling
to initiate loading of jobs to facilities.
• Expediting the critical job.

13. Objectives of scheduling
• To meet the due dates.
• To minimize lead time.
• To minimize setup time or cost,
• To minimize work-in-process inventory,
• To maximize machine or labour utilization.

14. Data Requirement
• The Production Scheduling requires accurate
information on:
• The current status of jobs (e.g., what orders
are in process and where);
• What upcoming jobs are available.
• The adequacy of materials and capacities.
• The equipment and labour utilization.
• Job progress and efficiency.

15. Type of Scheduling Tools/
Techniques
• Master Scheduling (Master production
Scheduling )
• The master schedule also known as master
production schedule (MPS), Formalize the
production plan and translate it into specific
end-item requirement over a short to
intermediate planning horizon.

16. Master Scheduling Vs Aggregate
Plan
• Aggregate Planning is the process of Planning
the quality and timing of output the medium
range (often 3 to 18 Months) by adjusting the
production rate, Employment inventory, and
other Controllable Variables.

18. Inputs to MRP
• The major inputs to the master production
schedule are:
• Forecast of demand of end items,
• Customer orders, and
• Inventory on-hand fro the previous period.

19. Function of MPS
• The main function of MPS-
• To translate aggregate plans into specific end
items.
• To evaluate alternative schedule.
• To Generate Materials requirements.
• To generate capacity requirement.
• To facilities information processing.

20. Flow Chart of Master Production
Scheduling

21. Gantt Chart
• Gantt Chart are simple bar graph that can be
used to schedule any type of operation. These
chart are named after its originator.
• Gantt Chart are usual (Bar Chart) aids used to
depict the sequencing load on facilities or
progress associated with work efforts over a
well-defined time period.

22. Gantt Chart
• Types of Gantt Chart- Gantt Workload Chart
1. A work load chart is usually used to depict
workload levels for equipment workstations
or departments.

23. Gantt Chart
• Gantt Scheduling Chart-

24. Perpetual Scheduling
• The copy of the order remains in the file until
the job is completed
• During the processing, the progress report is
reported with the help of the tickets such as
Inspection tickets, materials requisition
tickets, rework ticket, move tickets etc.,

25. Step-1 Making of Perpetual
Scheduling
• 1. preparation of load analysis sheet-

26. Step-2 Making Perpetual
Scheduling
• The total work load against each department
is added up and knowing the weekly capacity
of a department, the number of weeks load
against each department is calculated.

27. Scheduling n jobs on two Machine
(Johnson’s Rule)
• The objective of Johnson’s Rule is to minimize
the flow time from the beginning of the first
job until the finish of the last.
• In other words, Johnson’s Rule tries to
maximize the concurrent operating time both
the machines.

28. Problem Content
• The n Job 2-Machine Sequencing problem is
completely described as under-
• Only two machine are involved, say M1 and
M2.
• Each job is processed in the order (M1 and
M2).
• The exact or expected processing times for all
the job that minimizes the total completion
time.

29. Johnson’s Rule Steps
• Step-1 List the operation times, each job on
the both machines.
• Step-2 Select the shortest operation time.
• Step-3 If the shortest time is for the first
machine, do the job first. If the second
machine does the last job.
• Step-4 Repeat Step 2 and 3 for each remaining
job until the schedule is complete.

30. Scheduling n jobs on three
machine (n/3 Scheduling )
• Johnson’s method can be extended to yield an
optimal solution for the n/3 scheduling
problems.
• Problem Content: The n-Job 3 Machine
sequencing problems is described as follows.
1. Only three machine are involved say M1,M2
and M3.
2. Each Job is processed in the prescribed order
M1, M2 and M3

31. Scheduling n jobs on three
machine (n/3 Scheduling )
• No Passing of Jobs is permitted (i.e., the same
order over each machine is maintained).
• The exact or expected processing time on
three machine are known.
• The problem, again is to find the optimum
sequence of the job which minimizes the total
flow time.

32. Extended Johnson Rule
• The Johnson’s Rule can be extracted to solve
the n/3 scheduling problems where either one
or both of the following conditions hold good:
1. Maximum time on machine M1 ≥ Max time
on Machine M2.
2. Minimum time on machine M3 ≥ Max time
on Machine M2.

33. Extended Johnson Rule
• The method consist of replacing the given
problem by an equivalent problem involving n
job and two machines.
• The two hypothetical machines are denoted
by G and H and their corresponding
processing times are given by

34. Scheduling a set numbers of jobs
on the same Number of Machine
• The assignment method is a special case of
transportation method of liner programming.
It can be applied to situation where there are
n supply sources and n demand sources (e.g.,
five jobs on five machines).
• This method is useful in application involving
allocation of jobs to work center.

35. Graphical Procedure
• Construct a two dimensional graph where x-
axis represent the processing time and
sequence of job 1 on the m machine while y-
axis represent those of jobs 2 ( use the same
scale for both x and y)
• Shade the areas where a machine would be
occupied by the two job at the same time.

36. Scheduling 2 Jobs in ‘M’ Machine
• The processing of both jobs can be
represented by a continuous path which
consist of horizontal, vertical and 45˚ diagonal
segments.
The Path Starts at lower left corner and stops at
the upper right corner, while avoiding the
shaded area in the graph. In other words the
path is not allowed to pass through the shaded
areas.

37. BATCH PRODUCTION SCHEDULING
• Batch production scheduling is preferred
when a variety of product are to be made and
the volume are not large enough to demand a
separate line for each product.
• In batch production system, the output is
inventoriable and can be produced in
substantial volume.

38. Batch Scheduling
• In such situation, it is necessary to determine
the lot size for batch to be produced at one
time in addition to scheduling the batch on
the facilities.
• In other words, the decision to be taken in
batch production scheduling are:
1. The Economic Batch Size Decision, and
2. The scheduling decision (regarding when to
begin the processing of the batch)

39. Determination of Economic Batch
Quantity (EBQ)
• The EBQ formula can be reproduced as below

40. Batch Scheduling
• Batch Scheduling also Known as EBQ Scheduling
can be performed by using aggregate run-method.
1.Aggregate Run-out Method-
• Aggregate run out method also known as
aggregate run-out time method (AROT) method,
can be used to determine production runs for a
group of items that requires the same production
facilities.

41. Procedure for AROT
1. Compute the Aggregate run-out time (AROT)
of Each item required for a product.
2. Rank the items in the ascending order of
their run-out times (ROT’s)
3. Schedule the item with the lowest ROT first,
followed by the item with the next Lowest
ROT.

42. Line of balance
• Line of Balance (LOB) is charging technique that
uses lead times and assembling sequencing to
compare planned component completions with
actual component completions.
• The Technique is used to compare progress on
each operation with the progress that would
be required to meet the delivery requirement
to cope with market Demand.

43. Uses of Line of balance
• Source of Each component element (purchase,
Manufacture, Assemble, test, etc.,)
• Sequence of assembly, including sub
assembly, test and inspection, packaging,
shipping and relative activities.
• Comparison of schedule versus actual finished
product deliveries.
• Comparison of schedule versus actual
component showing present and potential
shortage or delay.

44. Various Charts of LOB
• Operation Chart.
• Objective Chart.
• Progress Chart.
• Line of Balance.

45. Operation Chart
• Operation Chart is also known as program
plan or production lead time chart or
assembly chart is chart that shows the lead
time for each operation stage/processing step.

46. Objective Chart
• Objective Chart shows the contrast between
expected completion schedule of production
and actual performance.
• The objective Chart Shows-
1. The Difference between the schedule and
actual deliveries,
2. The time lag between the schedule and
actual deliveries.

47. Objective Chart

48. Objective Chart

49. Line of Balance
• The line of Balance chart shows the quantity
of item that should have been completed at
each operation stage in a particular time at
which, progress will be reviewed so as to meet
the delivery schedule for the finished product
and to meet the completion schedule
quantities cumulatively.

50. Progress Chart
• The progress chart is a type of chart which
shows the actual number of items produced
at each operation stage against the quantities
that should have been produced as indicated
by the line of Balance.

51. Progress Chart

52. Material Requirement Planning
(MRP)
• Material Requirement Planning (MRP) is a
computational technique that convert the
master schedule for final product into a
detailed schedule for the raw materials and
parts used in the final product.

53. Input of MRP
• The three important inputs to MRP are:
1. Master Production Schedule.
2. Bill of Materials.
3. Inventory Record File.

54. Structure of MRP

55. Master Production Schedule (MPS)
• Master Production Schedule (MPS) is Detailed
Plan that states how many end items (i.e., the
final product to be sold to the customer) will
be available for sale or distribution during
specific periods.
• Inputs of MPS
1. Market Requirements,
2. Production Plan from Aggregate Planning,
3. Resources Available.

56. Inventory Record file
• All data related to the inventory are recorded
in the inventory record file.
• The inventory record file contains the
following three segments:
1. Item master Data Segment: It provides a time
phased record of Inventory status.
2. Subsidiary Data Segment; It provides the
subsidiary data such as purchase order, scarp
etc.,

57. MRP Outputs Report
• Primary Outputs includes-
1. Order Release notice, to place order that
have been Planned by the MRP System.
2. Report of Planned order Releases in future
periods.
3. Rescheduling Notices, to indicate the
changes in due dates for open orders.

58. Dispatching and Expediting
• Dispatching is the routine of setting
productive activities in motion through the
release of orders and instructions, in
accordance with previously planned times and
sequence, embodied in route sheet and
schedule charts.

59. Dispatching Activities
• The Following dispatching activities from
stores to the first process, and from process to
process.
• Issue of tool orders instructing, the tool
department to collect and make ready tools,
jigs and fixtures in advance of the time at
which the operation will start.

60. Dispatching activities
• Issue Job Order, authorizing operation, in
accordance with date and times previously
planned and entered on the machine loading
chart, route sheets and progress control
sheets or boards.
• Issue of time tickets, Issue of Inspection order,
Issue of move order.

61. Function of Dispatching
• To prepare manufacturing orders (which
consist of shop orders, move orders)
• Issue of materials from the stores.
• Issue of instruction to tool room.
• Issue of order authorizing the commencement
of operation in accordance with the
predicated dates.

62. Function of Dispatching
• Issue of time, time instruction cards, drawing.
• Issue of the order to the inspection
department.
• Ordering finished products to the finished
stock room.
• Time recording.
• Issue of time ticket to finance department.
• Recording of the idle time of machine and
operation.

63. Common Form used in Dispatching
• Material requisition.
• Job cards / tickets.
• Labor Cards/ tickets.
• Move Cards/ tickets.
• Inspection Cards / tickets.

64. Dispatching Rules
• When many Jobs are waiting before an
operation facility, we should have some rules
to decide the priority while dispatching.
• The most commonly used dispatching rules
are-
1. FCFS. 4. STR
2. SOT 5. Critical Ratio
3. Earliest Due date. 6. Queue Ratio

65. Expediting or Progressing
• Expediting also known as Follow-up
Progressing, is a control that keeps track of
the progress of work in accordance with the
planned.
• This follow-up is to be done at every stage in
production Cycle i.e., to follow-up of work-in-
process, and follow-up-of- assembly.

66. Expediting or Progressing
• Functions of Expediting-
1. Status reporting.
2. Attending to bottlenecks or holdup in
production and removing the same.
3. Controlling variation or deviation from
planned performance levels.
4. Following up and monitoring progress at
work through all Stages of production.

67. Expediting or Progressing
• Co-ordinating with purchase, stores, tool room
and Maintenance department.
Types of Progressing-
1. Programme Control.
2. Order Progressing.
3. Shortage Chasing.
4. Daily Plan Progressing.
5. Department progress control.

68. Recording Progress
• The most widely used one are as follows
1. Gantt Chart- Gantt Chart are used to provide
an immediate comparison between schedule
the actual progress of the work.
2. Visual Chart- Visual Chart is the variations of
the Gantt Chart. Using pin board.
3. Cumulative and weekly Chart- the cumulative
Chart shows how much we have managed to
produce so far.