Tema05 Material Handling

8/19/2019 Tema05 Material Handling

1/62

Cadena de suministroMtro. William H. Delano Frier


2/62

Cadena de suministro | Profesor William H. Delano Frier

Module 5

Material Handling


3/62


Syllabus

• Material Handling

• Objectives

• Principles

• Types of Material Handling Equipment

• Productivity

• Warehouse Distribution

• Selection process

• Service Levels


4/62


Introduction

• Material Handling includes all the basic operations

related to moving products within a facility using

some type of equipment

• Material Handling is not limited to movement, but

includes packaging and warehousing activities, taking

into account the time and space needed


5/62


Planning

• It´s important to plan movements due to the

following reasons:

• Represent an important component of the total

production cost

• Affects the operation and facility design


6/62


Planning

• Objectives

• Improve facility utilization

• Increase the material flow efficiency

• Reduce the handling cost

• Increase productivity

• Simplify the manufacturing process


7/62


Planning

• Risks of a poor material handling system:

• Queues / Delays

•Machine downtime• Late delivery of raw materials to the line

• High inventory

• Variation in production programs

• Labor security risks

• All this can be expressed in high costs and customerdissatisfaction reflected in financial losses


8/62


Planning

When performing materials handling planning the

following should be taken into consideration:

• Shorten transport distances as possible

• Use simple patterns

• Transport load in both directions

• Transport full loads• Take advantage of gravity


9/62


Materials Handling Principles

Planning Principles• The management of all material must be the result of a deliberate

plan where the needs and objectives are identified early on

Standardization principle• The methods, equipment, controls, and software management, the

material must be standardized without sacrificing flexibility

Principle of work

• The work of the material direction should be minimized withoutsacrificing productivity or the level of service required for theoperation


10/62


Material Handling Principles

Ergonomic Principle• The human capabilities and limitations should be

recognized to ensure safe and effective operations

Loading Principle• Unit loads will be classified and appropriately configured in

a manner that achieves the objectives of the flow of material and the inventory in each stage of the supply chain

Principle of space utilization• The effective and efficient use of all available space


11/62


Material Handling Principles

System Principle• The activities of the movement and storage of materials must be

fully integrated to form a coordinated system

Automation Principle• The material handling operations to be machined and automate

where feasible improve operational efficiency

Environmental principle

• Consider the impact to the environment when making a design

Life cycle cost principle• A thorough economic analysis should explain the entire life cycle


12/62


Material Handling Equipment

• Includes:

• Transportation equipment

• Warehousing System

• Unifying Equipment

• Identification Systems and Product Tracking


13/62


Transportation Equipment

• Main Handling Equipment:

• Conveyors

• Cranes

• Vehicles


14/62



ConveyorsCharacteristics :

• Continuous movement over a predeterminedpath

Advantages :• Moves high volume

• Speed may be regulated

• Loading and unloading at any point of thepath

• Move and merge with other operations

Disadvantages :By following a fixed path it serves certain areas

• Bottlenecks can occur

• A breakdown paralyzes the entire line


15/62



CranesCharacteristics :

• High lift equipment to move material

• Its use involves offsetting an opposing force

Advantages :

• Lift and move material

• Little interference with the working area

• It maximizes production floor based on itslifted installation

• Can move heavy loads

Disadvantages :

• Large investment

• It Serve a limited area

• Straight Movements


16/62



VehiclesCharacteristics:They can be manual or motorized

• They move load over variable routes

Advantages:Its use is not limited to a predeterminedroute

• Can load and move a load

• They serve multiple areas increasing itsuse

Disadvantages:Limited capacity (weight)

• Limited capacity per trip

• Requires predetermined aisles

• Operator required


17/62



Select the proper vehicle:

Depending on the load to move and

distance to travel, the following chart is

used to determine the type of transportation vehicles:

Some vehicles commonly used are:

Forklifts Trucks Pallet Trucks


18/62


Warehousing Systems

Bulk storage• Store materials in an open area

• Require little or no storageequipment

Rack• Structures designed to stack loads

vertically, thus increasing efficiency

Shelving and compartment• Shelves can include storage

compartments


19/62


Warehousing Systems

Drawer storage• To find items stored on shelves can

be difficult if the rack level is toohigh or too low or too deep

• The drawer storage is generallyused for tools, hardware, and othersmall items.

Automated systems

• Rotating carousel systems thatstore more than oneloading/unloading station.


20/62


21/62


Identification Systems and Product

Tracking

• Usually the product islabelled (directly to the item

or to the packaging) toidentify and keep track of it

• The most commonly used

label consists of bar codeswhich can be read rapidlyand automatically


22/62


Levels of Mechanization

Classification

• Depends on the driving source and the degree of participation of human and computer

Degrees

• Manual and human physical effort dependentTrucks

• Mechanized

Uses driving force instead of human physical effortOperator required to operate and not to provide thedriving force


23/62


Levels of Mechanization

• Degrees

• Mechanized supplemented with computers•

The computer generates documents indicating the route and the task.Automated

• Low human involvement

• The computer gets instructions from a control panel (human factor)AS / RS, AGV

•Fully automated• The computer produces the activation signal

• It eliminates the human factor


24/62


Productivity

Measurement

• In order to determine productivity it is necessary to

measure system effectiveness to determine if goals

are being achieved


25/62


Productivity

Index

• Material Handling – Labor (MHL)

• Equipment Utilization (HEU)

• Space utilization for warehousing (SSU)

• Percentage of Aisles(ASP)• Damaged Load Units (DL)


26/62


Index

• Material Handling – Labor (MHL)

• It can be measured in hours or $.

• The index should be:

• < 1 In General

• < 0.30 In The Plant

•> 0.30 In The Warehouse

HeadcountTotal

HandlingMaterialforHeadcount MHL


27/62


Index

• Equipment Utilization (HEU)

• The index should be closer to 1

• Warehousing Space Utilization(SSU)

• The index should be closer to 1

CapacityInstalled

hourpermovedKgHEU

SpacesAvailable

SpacesUsed

SSU


28/62


Index

• Aisle Percentage(ASP)

• 0.10 < ASP > 0.15

• Units of Damaged Load (DL)

• Measures the labor quality

SpaceTotal

AislesforSpaceUsedASP

loadTotalloaddamagedof unitsof #DL


29/62


Selection

• Factors• The factors that should be taken into account are:

• Material to be moved• Type, volume, weight, form, and size

• Displacing• Frequency, route, space for aisles, loading/unloading

• Warehousing

• Surface, volume, form and size

• Columns and docks

• Cost• Investment, operating cost, depreciation

• Other factors• Flexibility, obsolescence


30/62


31/62


Agenda

• Design• Discrete Modeling System

• Design Process / Permanent Location


32/62


Design

• The objective of the

design consists on

answering the following:

• Number of warehouses

needed?

• Warehousing and

Replenishment Methods?

• Product Location inside the

warehouse?


33/62


34/62


Layout TypesConventional types of layouts:

Fixed Position

Big and heavy product. The products remain in a single location during

most of the production time.

Position based on type of Process

A variety of products are manufactured in small or medium workdays.

The system must be flexible to support variations.

Position based on type of product

Standard production in high quantities (scaled production).

The automobile final assembly is designed as a product layout.

Design


35/62


Design

• Models

• Discrete Models

• The materials are considered static• Pallets, bags, containers

• Continuous Models

• The material is constantly being consumed

• Silos, tanks


36/62


• The location is assigned by two methods:

• Sequentially• Benefits

• Simple use

• Product is stored sequentially by item numbers

• Disadvantages• It Does not take into account the transaction volume

• Products with high turnover can be stored in farther away locations

• Transaction Flows•

Takes into account:• Activity Level

• Volume to be stored

• It is preferred over the sequential method

Permanent Location


37/62


Permanent Location

• Methodology

• Required Space

• Expected Service Level

• Costs

• Warehousing / Supply


38/62


Space Requirements

• The number of spaces assigned to a certain product

must be enough to store the maximum expected

volume.

Producto

Demanda diaria

(pallets)

Reposición

(pallets)

1 2 8

2 5 40

3 2 12

4 1 12


39/62


Space Requirements

• Example….Período Producto 1 Producto 2 Producto 3 Producto 4 Acumulado

1 8 1 0 2 5 2 5

2 6 5 12 4 2 7

3 4 4 0 10 3 5 7

4 2 3 5 8 2 4 7

5 8 3 0 6 1 4 5

6 6 2 5 4 12 4 7

7 4 2 0 2 11 3 7

8 2 1 5 12 10 3 9

9 8 1 0 10 9 3 7

10 6 5 8 8 2 7

11 4 4 0 6 7 5 7

12 2 3 5 4 6 4 7

13 8 3 0 2 5 4 5

14 6 2 5 12 4 4 7

15 4 2 0 10 3 3 7

16 2 1 5 8 2 2 7

17 8 1 0 6 1 2 5

18 6 5 4 12 2 7

19 4 4 0 2 11 5 7

20 2 3 5 12 10 5 9

21 8 3 0 10 9 5 7

22 6 2 5 8 8 4 7

23 4 2 0 6 7 3 7

24 2 1 5 4 6 2 7

Má xim o 8 4 0 12 12 5 9


40/62


Space Requirements

• Example…

• Total Space= 72 Pallets (8+40+12+12)

• Maximum used space in one day= 59

Total Space = Maximum Pi


41/62


Sizing on the basis of Service

Levels• Warehousing Capacity based on the probability of

missing space

• Where:

• Q j = Assigned spaces for the product j

• F j = Cumulative Distribution Function

Q

Q

j j

j j

n

1 j

n

1 j

n

1= j

F

F

1=1)esPr(faltant

=0)=esPr(faltant

Pj)para0=esPr(faltant=0)=esPr(faltantNo shortages)

No Shortages)

1 or more shortages

No shortages for product j)


42/62


Sizing on the basis of Service Levels

• Example.....

In the warehouse where 5 products are stored,

the Service Level should cover Mean +2.25 s. The

probability that a number of spaces required ona particular day can be approximated by the

normal distribution

Required spacesProducto Media Desviación Estandard

1 30 8

2 40 10

3 50 15

4 50 12

5 40 12

Product Mean Std Dev.


43/62



• Example...

• The number of spaces Q assigned to product j isgiven by:Q j = M j + z jσ j• where:

• M j = Mean of required spaces per day

• z j

= Safety Factor

• j = Standard Deviation for the required spaces per day


44/62



• Example…• Required Spaces

• Q1 = 30 + 2.25(8) = 48 spaces

• Q2 = 40 + 2.25(10) = 62.5 spaces

• Q3 = 50 + 2.25(15) = 83.75 spaces

• Q4 = 50 + 2.25(12) = 77 spaces

• Q5= 40 + 2.25(12) = 67spaces

Total = 339 spaces• Service Level

• F j = 0.5000 + Z2.25• = 0.5000 + 0.4878(from Table or Excel) = 0.9878

• Probability of Zero space shortages• F jQ j = (0.9878)5 = 0.94047• Probability of at least 1 space short per day

• 1- F jQ j = 1-0.94047 = 0.05952


45/62



• Optimization Decisions

1. Maximize the probability of having 0 (zero)

missing spaces :

0

asujeto1

n

1= j

Q

Q

QF

j

n

j

j

j j

S

Maximizar Maximize

Subject to,


46/62



• Exercise..

• Assign 100 spaces maximizing the probability of

having 0 spaces missing.

Espacios A B C D

5 0.1 0.25 0.1

10 0.1 0.2 0.2

15 0.1 0.25 0.3

20 0.1 0.2 0.4

25 0.1 0.25

30 0.1 0.235 0.1 0.25

40 0.1 0.2

45 0.1

50 0.1 0.2

PRODUCTOSProductsSpaces


47/62



• Exercise… Using the OM Transportation Model…

• Accumulated Frequencies…

COSTS A 1 A 2 A 3 A 4 Supply

5 0.1 0.25 0.1 310 0.2 0.2 0.3 3

15 0.3 0.5 0.6 3

20 0.4 0.4 1 3

25 0.5 0.75 2

30 0.6 0.6 2

35 0.7 1 2

40 0.8 0.8 2

45 0.9 1

50 1 1 2

Demand 1 1 1 1 4 \ 23

COSTS A 1 A 2 A 3 A 4 Supply

5 0.1 0.25 0.1 310 0.2 0.2 0.3 3

15 0.3 0.5 0.6 3

20 0.4 0.4 1 3

25 0.5 0.75 2

30 0.6 0.6 2

35 0.7 1 2

40 0.8 0.8 2

45 0.9 1

50 1 1 2

Demand 1 1 1 1 4 \ 23


48/62



• Exercise… Using the OM Transportation Model…

• Add a space matrix:

Shipments

Shipments A 1 A 2 A 3 A 4 Row Total5 0 0 0 0 0 0 0 0 0

10 0 0 0 0 0 0 0 0 0

15 0 0 0 0 0 0 0 0 0

20 0 0 0 1 1 0 0 0 20

25 1 0 1 0 2 25 0 25 0

30 0 1 0 0 1 0 30 0 0

35 0 0 0 0 0 0 0 0 0

40 0 0 0 0 0 0 0 0 0

45 0 0 0 0 0 0 0 0 0

50 0 0 0 0 0 0 0 0 0

Column Total 1 1 1 1 4 \ 4 25 30 25 20 100

Total Cost 0.5 0.6 0.75 1 0.225

ESPACIOS


49/62



• Optimization Decisions

2. Minimize the number of spaces to guarantee a

certain service level

0

asujeto n

i= j

1

Q

QF

Q

j

j j

n

j j

P

Minimizar Minimize

Subject to,


50/62



• Exercise…

• Minimize the number of spaces to guarantee a

service level >= 20%

Espacios A B C D

5 0.1 0.25 0.1

10 0.1 0.2 0.2

15 0.1 0.25 0.3

20 0.1 0.2 0.4

25 0.1 0.25

30 0.1 0.235 0.1 0.25

40 0.1 0.2

45 0.1

50 0.1 0.2

PRODUCTOSProducts

Spaces


51/62


Sizing on the basis of Costs

• Objective

• Minimize the Warehousing Cost

• Options to analyze:

• Warehousing owned storage space

• Leased Space

n j T t maxC t minC t Q jC oQ nQTC Qd Qd j jt j jt 1 1 ,2,1,...,1 0,, ,,


52/62



• Where,

• Qj = Owned storage capacity for product j

• T= Length of the planning horizon (periods)

• dt,j = Storage space for product j during period t• C0= Present worth cost per unit storage capacity

owned during the planning horizon T

• C1,t = Present worth cost per unit stored in owned

space during period t• C2,t = Present worth cost per unit stored in leased

space during period t


53/62



• To determine the optimal space

1. Calculate C’ = C0 / (C2 - C1)

2. Sequence the space demand in decreasing order

3. Sum the demand frequencies f

4. When the partial sum is equal to or greater than C’

then the optimum capacity equals the demand level


54/62



• Example....

• Which is the optimal space needed to store 1 product

during 10 periods, considering the followinginformation: Co = $20

• C1,t = $1

• C2,t = $4

• The space requirements are 4,6,8,10,9,8,7,6,5,4 during the

periods 1 to 10 respectively.


55/62



• C’ = 20/ (4-1) = 6.67

EspacioRequerido Frecuencia Suma f

10 1 1

9 1 2

8 2 4

7 1 5

6 2 7

5 1 8

4 2 10

Optimum Capacity

TC = $223

Req. Space Frequency Sum f


56/62


Assigning products to Storage /

Retrieval Locations

• Objective

• Minimize the time required to store and supply

products

• Requirements

• Have enough slots available to “assign” one to a product

• Define and keep the selection criteria

• Criteria• Minimize the distance travelled


57/62



Retrieval Locations

• Objective

k y jpara1,0

,.....,1,

,.....,1,1

:

)(

,

1,

1,

,,,1 1 1

x

S x

x

xt p

S

T

k j

js

k k j

n

jk j

k jk j ji

m

i

n

j

s

k j

j

n j

sk

asujeto

x f minimizar Minimize

Subject to,

For j and k


58/62



Retrieval Locations

Methodology

s = # of spaces

n = # of products to store

m = # of receipt and supply points

Sj = # of spaces required for product j

Tj = # of transactions for product j

pi,j = % of transactions from j to the receipt and supplypoint i

ti,k = Travelled time from I to space kxj,k= 1, if j is assigned to space k= 0, if not

f(x)= Estimated time to satisfy the system demand


59/62



Retrieval Locations

Methodology

• If j is assigned to space k;(xj,k =1)

• It takes tj,k time to travel from access I to space j and

vice versa

• Sj is the # of total spaces for j

• 1/ Sj is the probability to have a travel distance from /

to space k

• Tj # of transactions of j during the period• pi,j % of transactions from j to i


60/62



Retrieval Locations

Methodology

• Tj / Sj (pi,jti,kxj,k) represents the total travelled

time from:

• space k,

• To / from access point i

• For the product j


61/62



Retrieval Locations

• Exercise

Tenemos los sig. Espacios:

1 2 3 4 5P3 6 7 8 9 10

* 11 12 13 14 15

16 17 18 19 20

P2 21 22 23 24 25

* 26 27 28 29 30

31 32 33 34 35P1 36 37 38 39 40

* 41 42 43 44 45

46 47 48 49 50

We have the following spaces:


62/62



Retrieval Locations

• Exercise

• Access doors

• Probability of use P1= 10%, P2 = 40%, P3 = 50%

X Y

P1 0 20

P2 0 50

P3 0 80

Coordenadas Puertas

Si Ti Ti / Si

1 19 55

2 21 20

3 10 45

Transacciones y Espacios requeridos

Each shelf measures 10 x 10

Door Coordinates

Transactions and Required Slots

Tema05 Material Handling

Documents

Transcript of Tema05 Material Handling