Production Scheduling

－－ Dick Lam

Time present and time pastAre both perhaps present in time futureAnd time future contained in time past

There is a long process in Sales & Marketing before we are committed to PRODUCTION

Identify

Contact Meet Propose

Make Sale

Schedule

MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY SATURDAY SUNDAY

WEEK 1 27 28 29 30 1 2 3

WEEK 2 4 5 6 7 8 9 10

WEEK 3 11 12 13 14 15 16 17

WEEK 4 18 19 20 21 22 23 24

WEEK 5 25 26 27 28 29 30 31

Materals Planning

Master Production Schedule

Production

心寛室自大 , 室小心乃寛

2. All Other Functional DeptsIncluding Purchasing, Material, Engineering, Quality, HR & Admin, Finance & etc

Production – the core of a factory operation

1. ProductionAdd value to customers, needs support from every functional depts of the factory

Why matters?

Time

Production capacity cannot be stored

Workforce

Operators are not flexible actually

Inventory

Incorrect planning leads to increase in Inventory!

Expedite the order of ABC company, now!!

First thing first

Do the urgent thing first! Put down everything and just focus

on ABC order Production Manager and

supervisors should walk through the lines and ensure all people are doing ABC order.

WE are team. We can make it!!

2. All Other orders

ABC order – the most urgent order!!

1. ABC order

Shipped

ABC Order shipped

But All other orders are messy!!!

Caution!! XYZ is

Urgent!!

We need more capacity!!!

More Equipment/Facility

More Space/People

But there is nothing to do in production lines SOMETIMES!!!

Agenda

Scheduling – Model II (Sequential Processing, Pull & Push)6

Scheduling – Model I (Multiple Machines for Single Job Task)5

Scheduling – Simplified Version (Single Production Line)4

Scheduling Principles3

Excel – User Defined Functions Library2

Excel Basics1

Challenge up, Support Down

Contact Details

Mr. Dick Lam Chor Ki

dicklam128@hotmail.com

http://dicklam128 .wordpress.com

Disclaimer• No Best Practice provided in this course

• Only Low Hanging Fruit

• The Best Solution is unquestionably the ERP under the condition that you strictly follow the ERP environment specified

• HOWEVER, we provide you Bridges of:• Knowledge• Thinking• Operation

Scarcity

We only manage the time in terms of hours

Before doing anything

1. Excel Basics• Functions review

– Min, Max– Vlookup– Sumif, Sumifs – Sumproduct– Iferror

• Range Name– Define, Create– Dynamic Range

2. Excel User Defined Functions

• You can write some functions like “sum”, “sumif” with the parameters you define– e.g. =sumxy(Cell1, Cell2)– e.g. =factorial(Cell1)– The file stored should be with .xlsm

• You can also package all the user defined functions into a library.– The file stored should be with .xlam

Developer Environment

Library: DLSupplyChain.xlam

• The Excel library developed by Dick Lam for Supply Chain management

• It contains various functions for production scheduling model

• Be reminded to put in the same folder of your supply chain model, but you need to manually open it whenever you open any Excel files which use the functions contained

• Put it in the following folder:C:\Program Files\Microsoft Office\Office12\XLSTART

• The library will open automatically whenever you start up Excel

• However, for users without this library in the above folder(particularly you distribute the file to others), they cannot see the result but “error”

Add-in

• Put it in any folder while the following is preferred:C:\Documents and Settings\user\Application Data\

Microsoft\AddIns

• Then go to register it in the Add-in manager

3. Scheduling Principles

• Pull or Push principles• First Deliver First Scheduled• Identify Weakest Link/Critical Path and

then exploit• Identify the non-critical Path as well as the

spare capacity• Schedule the identical/similar components

in continuous order

不知其源 , 焉知其流 ?

Master Production Schedule

For formula construction, please refer to the:

Master Production Schedule.xlsx

Excel ModelWorkshop

Basic Formula• Opening + In – Out = Closing

• Opening + Production – Sold = Closing

• Production = Closing – Opening + Sold

• Closing = Summation of Units to be sold of future days covered by Target Inventory Days

Using today capacity for tomorrow demand

Future spare capacity cannot be used to cover today/yesterday unfulfilled demand

MPS – Full Model

The user defined function is included in the library of “DLSupplyChain.xlam”

4. Single Production Line• It is scheduling of various job orders in a

single production line• Focus on the achievability of job orders• Results:

– When to start and when to complete– How many hours to complete including set up

& set down time– How many hours of spare capacity and how

many quantity not achieved– When to change die

A Snapshot

• It is the core of all kinds of scheduling

– Multiple machines for single job task

– Sequential processing

Excel ModelWorkshop

5. Multiple Machines for Single Job Task

• For multiple job orders, says 100 within a week, which use the same kind of machinery or production lines, it is to allocate job order to related machines/production line with consideration of certain conditions (constraints) and tell the user if it can be achieved.

Parallel Processing

Model Highlight

• Based on the priority of the machines & expected completion date, it will assign quantities to various equivalent machines so as to meet the expected completion date.

• A line schedule is produced telling the following:– What orders to produce over a certain period of time

(week by week)– When to switch product– How many operators required

A Snapshot

There is spare capacity for Job No.12 in R102 but the end date will be after ready date, therefore, it is allocated to R103

Job No.9’s ready date is Feb 4, but the capacity of days on and before Feb 4 have been used up, so it is allocated to R102; however, Job No.10 being with Feb 5 can stay on R102

Excel ModelWorkshop

6. Sequential Processing

• For job orders which requires >1 sequential processes, or even with more together with parallel processes of pre-conditions, it is to allocate the job orders to related process and evaluate whether it can be completed on time

Sequential Processing

Pull vs. Push

• Pull: Deadline/Delivery Date set, then see if it can be met after scheduling trial

• Push: Schedule production, process by process and define the Deadline/Delivery Date

A Snapshot

Excel ModelWorkshop

Conclusions – 3 Steps Planning

1Master

Production Schedule

2Materials

Requirement Planning

3 ProductionScheduling

Define your conditions

• Time gap between Delivery Date & Production Completion Date (Target Inventory Weeks)

• Identify the capacity flexibility

• Identify the weakest link

Sales get the order

Eager to meet customer expectation by internal strength

Operation Cycle

SCM lays the path

Does the MPSPlans the materialsSchedules the production

Production follows schedule

Utilize available hours to profit

To enroll the course

• Hong Kong, contacttraining@universal-hk.net

• Shanghai, contactenquiry@medglory.com