6- Lean Flashcards

1
Q

Where did lean orginate?

A

Japanese auto companies, especially Toyota

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What external factors drove Lean operations? x3

A

Small domestic markets => need to export

Highly regulated economy => difficulties in supplies

Strict labour laws => no cheap immigrant workforce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Difference between Lean and Taylorism?

A

Taylorism: high division of labour
Lean: highly skilled labour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Toyta Production System Lean Characteristics? [8]

A

Elimination of waste (value-creating activities)

Just in Time Synchronisation

Levelling

Pull Control

Continuous improvement

Automation

Teamwork

Visualisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

To manage value, Lean uses 3 principles:

A

Eliminate waste

Involve everyone

Improve continuously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

7 Types of waste

A
Inventory
Overproduction
Waiting
Unnecessary transportations
Processing waste
Inefficient work methods
Product defects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Whats the difference between Internal and External Activities?

A

Internal activities
can only be done when machine not running
-> directly affect changeover time

External activities
can be done when machine is running
-> do not affect changeover time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the characteristics of lean Cell Layouts? 4

A

Functional layouts do not pre-select transforming resources - create WIP, delays, unnecessary movement

Cells group all transforming resources (machines and tools) necessary to process similar types of transformed resources that are pre-selected

Compactness => cell layouts make WIP almost impossible to form

Benefits of cell layouts: reduced changeover times, high utilisation, ease of cross-training operators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

5 Benefits and 5 Drawbacks of Small-scale process technology in cell layouts:

A
Benefits:
Cheap tooling, but may reduce utilisation
Easy to move and re-configure
Quick to set-up
Flexible scheduling
Easy maintenance
Drawbacks:
Expensive tooling, economies of scale
Hard to move
Slow to set-up
Inflexible scheduling
Expensive maintenance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is Line Balancing?

A

To reduce waste due to idle time, workload must be balanced evenly across the workstations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Traditional mass production involves a lot of ‘___ workers’ who do not directly contribute to value

Traditional mass production also gives little ___ to workers because ____ of labour assigns autonomy to managers

Well-trained, motivated workers are the heart of Lean; they are given more ____but also expected to do more

Workers can be ___-trained to perform several parts of a process and operate variety of machines, adding to ____ and helping ___ ___

A

Traditional mass production involves a lot of ‘indirect workers’ who do not directly contribute to value

Traditional mass production also gives little autonomy to workers because division of labour assigns autonomy to managers

Well-trained, motivated workers are the heart of Lean; they are given more autonomy but also expected to do more

Workers can be cross-trained to perform several parts of a process and operate variety of machines, adding to flexibility and helping line balancing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Continuous Improvement:

Lean workers have responsibility for ___ and must take part in continuous ____

P___ ___ skills are trained

T___ ____ systems (andon) can be used to signal problems at workstations

Amazon.com: service agents are able to ___ products out from the website if they suspect that the product has repetitive ____

A

Lean workers have responsibility for quality and must take part into continuous improvement

Problem solving skills are trained

Traffic light systems (andon) can be used to signal problems at workstations

Amazon.com: service agents are able to pull products out from the website if they suspect that the product has repetitive faults

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the formula for Work In Progress?

What are the consequences of not controlling WIP?

What do the other to variable in the WIP formula mean?

A

WIP = throughput time × arrival rate

If we do not control this, fluctuations in throughput time will occur, disrupting the smoothness of output flow

Arrival rate: rate at which jobs are assigned to the system
Throughput time: is the time that it takes for a product to be manufactured.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Advantages of Reduce inventories

A

Permit greater flexibility in scheduling
Quicker response to changing demand
Can be used with EOQ model

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a push system?

Which way does information move?

What may happen if next work station is not ready to commence?

What systems are normally used to control?

A

Push system: output is pushed into the next work station once it is completed

Information moves forwards in the system

Work may pile up into WIP inventories if the next work station is not ready to commence

Implemented by automated MRP / ERP systems that seek system-wide efficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a Pull/Just in time system?

Which way does information move?

How does work move?

What systems are normally used to control?

A

Pull system: output is pulled from the preceding station once it is needed for the next stage

Information moves backwards through the system

Work moves just in time for the next operation

Implemented by manual Kanban systems
[Kanban cards provide the authorisation to move parts]

17
Q

Close supplier relationships:

Traditional systems allow to use __ __ for quality inspections and returns

__ __ ___ systems do not allow ___, therefore poor quality disrupts the smooth flow of goods

Inspections do not __ __ and are Muda

Close supplier relationships in ___ systems allow achieving high ___ levels

Moreover, __ __ __ systems emphasise close supplier relationships to allow small ___ sizes

A

Traditional systems allow to use slack time for quality inspections and returns

JIT systems do not allow slack, therefore poor quality disrupts the smooth flow of goods

Inspections do not add value and are Muda

Close supplier relationships in Lean systems allow achieving high quality levels

Moreover, JIT systems emphasise close supplier relationships to allow small lot sizes

18
Q

Define MURA, MURI and MUDA?

Key concepts in lean process thinking, like the Toyota Production System (TPS) as one of the three types of deviation from optimal allocation of resources

A

MURA = Un-evenness

MURI = Over-burden

MUDA = Waste

19
Q

Explain Preventive maintenance using 5S?

To lessen the probability of workplace incidence/failure

[2 of them basically the same]

[in fact most of them are, it’s basically a joke]

A

Sort (Seiri) – Eliminate what is not needed and keep what is needed

Straighten (Seiton) – Position things in such a way that they can be easily reached whenever they are needed

Shine (Seiso) – Keep things clean and tidy; no rubbish or dirt in the work area

Standardize (Seiketsu) – Maintain cleanliness and order – perpetual neatness

Sustain (Shitsuke) – Develop a commitment and pride in keeping to standards

20
Q

x4 Ways to implement Lean? The 4….

A

Philosophy – spread culture first, techniques follow

Process – value-focused and value-stream driven

People – implement through staff and patient buy-in of Lean

Problem solving – implement through innovation events and workshops

21
Q

x10 Reasons why Implementation of lean fails?

Anagram

A

Poor strategic integration
Conflicting measures (McMahon, 2013)
Relying on a champion
No leadership involvement

Lack of employee understanding
Employees not engaged
All education – no implementation
Forgetting the customer

Copying others
Lean as a project

22
Q

Scheduling in Large Batches:

What is Non-levelled and Levelled Scheduling?

What are the disadvantages of Non-levelled?

A

Levelled Scheduling is a Manufacturing technique that aims to create a smooth flow of production over a period. Its objective is to minimize disruptions caused by sudden changes in demand levels by matching the product family schedules with product-by-product schedules. Both the sales and production departments must agree on a fixed level of output volume and output duration.

Non-levelled creates a build up of inventory that has not adding value, just sitting idle as spare capacity.

23
Q

Small Production Lots:

What does it describe?

A

describes the manufacture of a small number of items of the same type and design.

Leads to smaller average inventories over time as more replenishments made - greater flexiblity