Week 7: Material Handling and Plant Layout

Question 1

What are the effectiveness measures of material handling(3)?

Answer 1

• Total material flow: the mass of material that is transported multiplied by the distance that it is transported
• Material handling labour ratio: indication of how much work needs to be done to handle material. The number of personnel working on material handling divided by the total number of personnel
• Equipment utilisation: a general measure that is used to gauge effectiveness of material handling. Actual output of the manufacturing system divided by the theoretical output

Question 2

What are the 10 principles of material handling?

Answer 2

1. Planning principle: all material handling should be the result of a deliberate plan
2. Standardisation principle: material handling methods, controls and software should be standardised
3. Work principle: material handling work should be minimised without sacrificing productivity or the level of service
4. Ergonomic principle: human capabilities and limitations must be recognised and respected
5. Unit load principle: unit loads shall be appropriately sized and configured
6. Space utilisation principle: effective and efficient use must be made of all available space
7. System principle: material movement and storage activities should be fully integrated to form a coordinated operational system
8. Automation principle: material handling operations should be automated/mechanised where feasible
9. Environmental principle: environmental impact and energy consumption should be considered.
10. Lifecycle cost principle: a thorough economic analysis should account for the entire lifecycle of all material handling equipment and resulting systems

Question 3

What do the symbols mean in the following formula?

Tc = Tl+Ld/vc+Tu+Le/vc

Answer 3

Tc - delivery cycle time
Tl - time to load at station
Ld - distance travelled loaded
Tu - time to unload
Le - distance travelled empty
vc - velocity of the carrier

Question 4

What do the symbols mean in the following formula?

AT = 60AFt*Ew

Answer 4

AT - available minutes per hour per vehicle
A - availability
Ft - traffic factor
Ew - worker efficiency

Question 5

What do the symbols mean in the following formula?

Rdv = AT/Tc

Answer 5

Rdv - rate of delivery per vehicle per hour
AT - available minutes per hour per vehicle
Tc - delivery cycle time

Question 6

What do the symbols mean in the following formula?

WL = RfTc

Answer 6

WL - total workload
Rf - total required flow rate
Tc - delivery cycle time

Question 7

What do the symbols mean in the following formula?

nc = WL/AT = Rf/Rdv

Answer 7

nc - number of required carriers
WL - total workload
AT - available minutes per hour per vehicle
Rf - total required flow rate
Rdv - rate of delivery per vehicle per hour

Question 8

What are the four types of plant layout?

Answer 8

1. Functional
2. Fixed Position
3. Product
4. Cellular

Question 9

Define functional plant layout

Answer 9

Functional: where resources are grouped according to the process they perform. Parts are moved between various departments in order for operations to be carried out. Effective when part variety is high but part volume is very low (job shop)

Question 10

Define fixed position plant layout

Answer 10

Fixed position: where moving resources are brought to the stationary part as required

Question 11

Define product plant layout

Answer 11

Product: where resources are grouped according to the sequence of operations required by the parts. Effective when part variety is low and part volume is high (mass production)

Question 12

Define cellular part layout

Answer 12

Cellular: where parts are grouped together into part families and resources are grouped according to the process requirements of part families. Also called group technology (cellular manufacturing)

Question 13

Describe systematic plant layout

Answer 13

1. Group resources into appropriate departments
2. Calculate the flows between the departments
3. Rank the flows and determine flow based relationships between the departments
4. Determine the non-flow relationships into the overall relationship matrix
5. Combine the relationships into the overall relationship matrix
6. Construct a relationship matrix
7. Calculate the space requirements for the various departments
8. Redraw the relationship diagram and scale departments
9. Construct a block layout