Tuesday, 21 June 2011

Your essential guide to lean success

Lean is made up of a plethora of complex theories. WM offers a handy reference guide to the kaizen team and how to employ them to ensure continuous improvement success at your site

Max Gosney Editor of Works Management Magazine kindly gave me permission to post this article on the Leanpal  blog.

http://www.worksmanagement.co.uk/article/33778/Your-essential-guide-to-lean-success.aspx 
  
Seven secrets to lean success
Lean, kaizen, continuous improvement- the pursuit of making your factory a more efficient and productive outfit goes by many names. But some golden rules ring true whatever your definition. WM gives the lowdown on seven top habits of lean success. Also, see the panel below for a lighthearted look at the key members of the lean team.

1 People power
'Died due to lack of staff support.' The words could be etched on the tombstones of many a failed lean initiative.

Popular backing will catapult a continuous improvement scheme into an unstoppable force. But resistance will quash it like a poison. Winning over your workforce is about empowerment, says Terry Carmichael, who led a lean programme at Thorn Lighting's Spennymoor site that helped the company win top prize at the Best Factory Awards in 2008.

"We insist on the involvement of our workforce in our improvement programme... It was traditional for our engineers to design our production lines, give them to operators and say get on with it. Now our people design their own work stations."

The simple change has reinvigorated the workforce, adds Carmichael. "The motivation of our people is fantastic because they really feel they've made a difference."

But, it's not just shopfloor support that holds sway over improvement bids, according to Mark Colvin of lean consultancy Leanpal. "For me, the absolute key is making sure senior management are behind the programme. That means not just committed through words but deeds as well." A stop-start approach fuels cynicism in workers, as factory managers at the recent Best Factory Conference were quick to testify. Continuous improvement programmes become branded as just another fleeting management initiative and are hamstrung by the burdens of past failures..

2 Tackling resistance
Cavemen, citizens against virtually everything, type Cs... Whatever their tag, the anti-change element of your workforce needs to be tackled if lean is to thrive. "We had those we described as cavemen who stood against everything," explains Carmichael. "Because we won the people over by talking about morale and we had some impressive results, the cavemen either changed or left."

Overcoming the resistance is about waging a tactical battle, says Carmichael: "Nobody likes to feel like they can't perform in the environment provided. It makes them feel, in their own words, inadequate. The other thing is when the rest of the organisation starts to rebel and peer pressure takes over."

Manufacturers can also look to avoid creating the breeding ground for saboteurs, according to Colvin. "Lean can often be perceived as all about redundancy. I've worked with companies which, if they need to make redundancies, do so before beginning the lean programme. That way you are working with staff who know they are part of the future and can get behind the ideas."

3 Make the time
Toyota – widely regarded as the godfather of modern lean manufacturing – puts good continuous improvement down to one thing. "The difference between success and failure is time," says Tony Wallis, operations director at the manufacturing giant's UK forklift business, Toyota Material Handling. "We create the time for our people and our leaders to give us continuous improvement. When I see it fail, it's because it's become flavour of the month... People don't allow the time for the leaders in their team to give input."

4 Suggestion schemes
Staff suggestion schemes are a gold mine for continuous improvement. Yet this cheap and simple source of lean ideas is often ignored by UK manufacturers. One company that's capitalised from the concept is boiler manufacturer Vaillant. The company delivered efficiency gains worth nearly £600,000 in one year through implementing suggestions, explains Allan Harley, improvement manager. "We use a pre-treatment to clean the metal on our boilers... with between one and half and two million parts, that means a massive volume of water. Two individuals at our Belper plant suggested we recycle it, run a filter system, and get rid of the water every three months instead of every time we used it."

Cynics will point out that enthusiasm for suggestion schemes, like lean itself, can falter after early gains. Vaillant, though, has proofed its scheme so the kaizen production line keeps on flowing. Harley says: "From the suggestion scheme we will generate kaizen blitz or kaizen weeks. Contributors get a cash reward based on what we've saved. But just for taking part we organise prize draws where you could win a weekend away or an iPod."

5 Leadership
A great leader can inspire staff to walk through walls to deliver improvements. A bad one will antagonise workers and stir them only to sabotage anything the boss might get rewarded for. The difference is all about vision, communication, trust and recognition, according to lean experts.

A common misconception is that leaders must be dominant characters often seen booming out instructions on the shopfloor. In fact good leadership is a subtle art, says Carmichael. "If you want people to build a ship don't ask them to collect wood and nails, just inspire in them a desire to sail the seas and the rest will happen by itself."

The best team leaders set a vision, help the team understand the goal and coach performance in key areas, says Dennis McCarthy of DAK Consulting. Regular performance feedback is a must, with staff encouraged to assess their own skills rather than be given a static lecture. Carmichael adds: "Catch people doings things well and reward them rather than catching people doing things badly and take other measures."

Once you have honed your team's skills , unleash the ultimate motivational tool – put individuals in charge of a key project and give them a pat on the back for success.

Opportunities to lead projects and win praise from managers are significantly more effective motivational tools than pay rises or cash bonuses, according to a 2009 survey by the McKinsey business journal. Crack the art of delegation and you won't have a single leader but a powerful raft of lieutenants championing your lean agenda.

6 Set a vision
Without a clear target to aim for, you will always be subsumed by dealing with the daily grind. The vision should be a compass for business activities, according to Toyota's Tony Wallis and Thorn Lighting's Terry Carmichael.

The targets should be filtered down through your organisation through Hoshin planning (see box, p18). Pinning your raison d'ĂȘtre up somewhere where everyone will see it is also a top tip.

7 Go to the source
If you can't see the problem, then you can never hope to find the solution – the 'go and see' or Genchi Genbutsu principle is a key pillar of the Toyota Production System.

"Any leader in any organisation that doesn't go to the source of the problem doesn't understand what needs to be put right," says Wallis. "We very clearly drive Genchi Genbutsu... If you watch and understand and talk to the team, you will understand what the problem is."

team kaizen

Name: Kanban
What is it: A signalling system used to regulate the supply and demand of materials in a production process. Kanban is the conductor-in-chief of manufacturing telling you what to make, when and to what quantity.
Strengths: Universally applicable, can drastically reduce stockholding, cuts waste, aids just in time (JIT) delivery
Weaknesses: Inflexibility – dramatic spikes in demand or the influx of new orders can upset the kanban
Kaizen rating: 8/10 A proven player in any successful lean manufacturing bid

Name: Hoshin planning
What is it: A process of goal setting where the business sets an overall target and gears staff towards hitting it via defined performance objectives.
Strengths: Gives a sense of purpose and direction, helps you diversify from competitors, powerful tool for enhancing staff performance, can help you navigate business risks
Weaknesses: A slow burner, goal setting involves staff feedback and fine tuning objectives can take several years. The process of strategic planning is also a diary drain and involves lots of away days.
Kaizen rating: 9/10 Fail to prepare, prepare to fail

Name: Poke yoke
What is it: The art of mistake proofing, poke yoke encourages staff to seek out and eliminate any flaws in work processes and products. Poke yoke inspired inventions include circuit breakers and locks that stop you taking the car keys out until the car is in neutral.
Strengths: boosts product safety, improves workstation design, low resource tool
Weaknesses: staff may be reluctant to admit errors
Kaizen rating: 8/10 A powerful self assessment technique that can weed out costly oversights

Name: Total productive maintenance (TPM)
What is it: TPM aims to involve all parts of an organisation in ensuring the effectiveness of production equipment and banishing time lost to breakdowns and stoppages.
Strengths: Allows you to make more and sell more, prevents costly downtime
Weaknesses: Takes a lot of time and resource as you're involving all areas of the business
Kaizen rating: 8/10 Prevention is better than cure

Name: 5S
What is it: The five Japanese words starting with S can be translated as: sort, straighten, shine/sweep, standardise and sustain. 5S ensures a clutter-free, optimum, working environment that leads to happier, more productive people, according to the theory.
Strengths: Productivity gains with less time hunting for parts, cleaner and safer environments increase product quality, and boosts morale.
Weaknesses: Can be difficult to quantify the gains as 5S offers a series of small improvements, heavy staff training
Kaizen rating: 9/10 5S can help you clean up on continuous improvement

Name: Value stream mapping
What is it: A diagram of the physical and information flows that contribute to a production process. The map highlights the value adding steps needed to produce the final goods.
Strengths: Allows a quick and easy reference point for strengths and weaknesses in the production cycle. Focuses staff on adding value and encourage employees to think outside of their own department. Value Stream mapping is highly versatile and can be used in back offices as well as on the shopfloor.
Weaknesses: Requires a lot of time to set up and extra training may be needed to help staff get to grips with the graphics.
Kaizen rating: 8/10 Steer the shortest path to improvement

Name: Six Sigma
What is it: A data-driven methodology that strives to remove variability and defects from manufacturing processes. Six Sigma borrows from martial arts disciplines by introducing expert green and black belts to further teachings.
Strengths: Highly effective problem solver, reduces defects, cuts waste
Weaknesses: Time consuming and requires heavy staff training, highly advanced and can be like using a sledgehammer to a crack a nut in some businesses, say lean advisors.
Kaizen rating: 8/10 The big gun of the kaizen team – best handled
with care

Want to become a continuous improvement king? Join WM's new CIN network: share valuable experiences with your peers and have an expert guide to help steer your successful lean journey. Contact
Richard Henley on 01322 221144 or email rhenley@findlay.co.uk
  Author
Max Gosney    
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Wednesday, 25 May 2011

Case Study - Practical Application of Kanban in a Complex Assembly Operation


This case study covers the implementation of a Kanban system for a more complicated range of products – the steps leading up to the implementation are described as is the change management process. 

The information presented has been desensitised - the company and its products are not identified for confidentiality reasons. 
It is divided into the following sections:-

·         Background
·         Value-stream mapping
·         Customer demand analysis
·         Kanban loop and card design
·         Advantages of the Kanban System
·         Change management
·         Summary

Background

The company, which we will call XYZ Ltd, is a division of a global concern.  It produces a range of complex and sophisticated electro-mechanical assemblies, employing over 200 people.

There are 15 live products of similar overall appearance but with different sizes and different functions. Demand is not equally split between the products. 

There are 8 sub-assembly lines feeding one common process (which we shall call the gluing line) from there on to 6 calibration/testing stations.

The sub-assembly lines are roughly split by product size, but also include new lines where new products have been developed and installed.  The test lines are also split by product size and age.

The gluing station is not particularly complex, but all the products are glued. The glue typically takes 36 hours to set. A series of roller tracks holds the products waiting to set before testing.


Sketch below shows a schematic of the process flow.




Leanpal got involved with the project because the overall productivity of the factory was deemed to be too low.  Throughput was less than expected, and the products were not coming off the lines in the expected order for the end customer.

The initial project was scoped as an exercise to improve the throughput of the calibration/test department, where it was thought that the changeover time (taking products off the test stations and replacing them with the next product to be tested) was constraining the overall output of the factory.

The supervisor of the calibration/test department, whilst open to the improvement project, maintained that the changeover time (and his department) was not the bottleneck - it was the way that the products arrived at the department which held up the overall throughput.

This was quickly investigated and found to be true.  The calibration and test was split into different product families, and could handle up to 11 assemblies any one time across six test lines.

In practice large amounts of the same size product were presented to the calibration test department at the same time.

Never mind waiting for a bus and three turn up at once – a better analogy would be like waiting at a main line rail terminus in London only to find that the first 30 trains were all going to Wales, the second 30 were going to Scotland and the third 30 were going to Cornwall rather than 1st train : Wales 2nd:  Scotland 3rd: Cornwall 4th: Wales etc.

The planning system already in place relied on line supervisors constantly scheduling and re-scheduling according to the master plan, without taking into account the queuing at the common process. 
Assembly lines were also manned by individual teams who concentrated on optimising their line performance without being aware of the bigger picture.   

This meant that labour transfer to meet demand across lines was rare and expediting critical items through production was frequent and disruptive (one senior manager spent almost all of his time on this activity).

Leanpal advised the senior and middle management that a Kanban system throughout the factory could increase throughput and conformance to customers’ schedule by better ordering the presentation of assemblies to the calibration/test department.

Value stream mapping

Value-stream mapping exercises were carried out across three of the eight assembly lines to improve the line layout, task balancing, single piece flow and pull production within the assembly lines themselves.  

It became apparent that despite the scheduling carried out by the line supervisors, assembly teams took it upon themselves to change the plans dependent on their personal build preferences.

The tail was wagging the dog.

Not only were the products’ arrival at the gluing station not being coordinated, the assembly of the products within the 8 lines were not being carried out in accordance with the plans.

Value Stream Mapping also revealed that the opportunity for significant productivity savings through task balancing within the lines, not to mention across the lines.

Customer demand analysis

The overall production demand pattern was analysed using Pareto analysis, and broadly split into runners, repeaters and strangers depending on the volume of throughput.  A “model plan” was developed to explore how the runners repeaters and strangers should (in theory) be presented to the gluing line in order to optimise the delivery of finished assemblies to the calibration/test lines.

Kanban loop and card design

Kanban cards were designed and pre-printed for the runners and repeaters. 

Blank Kanbans for the strangers allowed the product name or specification to be handwritten into the Kanban.

It became clear that two Kanban loops were required – one between test & gluing, plus one to pull products from assembly to the gluing line.

The system was designed so that only the test supervisor received a copy of the customer orders to be processed.  As runner/repeater products passed testing, the (blue) Kanban cards taken off these products were placed in the back of a Kanban box situated close to the gluing line.  This triggered a differently coloured (red) Kanban card to be sent to the eight individual assembly lines, each of which had its own Kanban box.

The red Kanban card signalled the assembly line to build the product, the build order was dictated by withdrawing the card from the front of the box.

The products assembled with red Kanban cards reached the gluing line, the red cards were replaced with blue cards, then the red cards were filed in part number order waiting for the next call off.

Staff on the gluing line were responsible for matching the assembled products with the blue Kanban cards in the order dictated by the cards coming out of the bottom of the (blue) Kanban box.

This ensured that the products going through the gluing line were processed in the order required by the testing station despite the 36 hour lag time as the glue hardened.

The sketch below shows a schematic of the line and the Kanban Loops 










Advantages of the Kanban system

The whole process significantly improved delivery measured by OTIF (on time in full) by smoothing the flow through the gluing and testing processes.

Due to the visual nature of the Kanban cards, where assembly lines had no product to be pulled, the supervisors found it much easier to manage the movement of assemblers to different assembly lines where the products were required.

Change management

The implementation of the Kanban System represented a significant change for the assembly line personnel.  They were used to managing the pace and order of their own assemblies according to their preferences, and generally stuck to one particular type of assembly rather than crossing line boundaries. Night shift and day shift competed on assembly numbers by attempting to produce the easiest products rather than the ones which were actually required by the customer according to the schedule.

Individual line and shift targets set by management had encouraged this behaviour in the past.

The installation of the Kanban System smoothed the overall flow through the factory, but forced the assemblers to build strictly in the order required by the customer, and to be flexible between easy/difficult products and across the production lines.

The design of the card system itself, the Kanban boxes, and the need for strict discipline in terms of ordering the Kanban cards was also a significant change.

In order to address this culture change, the complete system was extensively modelled with stickle bricks representing products, card labels standing in for Kanban cards and cardboard boxes standing in for the Kanban box. 

Initial table-top simulations were tested by a small team of four managers and production engineers. Then glue line, assembly line and test line supervisors were taken through the simulation to model the process and deal with any questions.

Having proved the system worked through the simulation, real Kanban cards and boxes were produced and installed on the factory floor, flow charts and standard operating procedures were drawn up to explain the process and awareness sessions were run for all the shop floor personnel to explain the system.

Summary

The installation of the Kanban system took several months to design and develop.  Whilst the concept of Kanbans is relatively simple, the devil was in the detail : understanding the demand pattern, where the issues were and how to design the practical application.

Understanding lean and the overall picture needed to be developed across senior management, middle management and shop floor staff.   

The project would not have succeeded without significant application of resource from the company to analyse the detail and adapt the system into something which would work within the company. 

Nor would the project have succeeded without a strong management champion capable of seeing the big picture and committed to addressing the whole rather than fire fighting individual departmental issues.

Thursday, 30 December 2010

Leanpal - Practical Application of Kanbans


This postexplores a practical application of Kanban systems

What do we mean by Kanban?  – (Experienced readers can skip this paragraph).

Kanban is the Japanese word for ticket – the practice originates from a factory calling off the parts it needs from stores or from another downstream production cell when it needs them and not before. This is why the term Kanban is so closely associated with “Pull” production or JIT (just in Time)

Let's explain this with a real example demonstrating the difference between push and pull production, and how we helped a factory start a basic Kanban system. 

The system is not finished or perfect – it’s rather a Work-in-Progress!

The factory has 2 production departments: Cell A supplies Cell B with volume work. 

(There are other departments and satellite supply sections – for simplicity this explanation ignores them – in practice of course we had to build the Kanban System taking them into account.)

Before Kanban

The company manages the “high level” production planning very well. They have visual management showing incoming orders and their due date broken down into weekly and daily timeslots.
Incoming orders from the customer are divided into manageable portions automatically according to pre-set rules. A computer system then issues the orders direct to a printer in Cell A, where they are printed as and when they hit the printer queue.

At this stage the supervisor of cell A selects the order, matches it to a set of standard work instructions, and hands it to the team leaders responsible for the individual machines within the cell.

The team leaders/machine operators tend to pick which job to start first – in theory this should be prioritised according to the(end customer) due date, although in practice the jobs may be processed out of sequence e.g.  easier jobs are done on this shift and more difficult jobs left for the next shift.

This system “pushes” production to Cell B which may not be in the best order for the customer.

Overproduction of certain items well in advance of their required due dates physically blocks the gangways of Cell B and causes double handling of stock, as the parts required have been blocked in by parts not required at that time.  
Sometimes cell B cannot start work on a pressing customer order as it has large stocks of one component for the final build, but zero stock of the other component required to make up the assembly.  
Six of the classic seven wastes are seen in this process:- transport inventory motion waiting overproduction and defects.

Practical Application of Kanban – Phase 1

In the process described above, the company already has a “ticket” to call off production according to the end customer needs – however it is pushing this from Cell A to Cell B. The solution is to allow by cell B supervisor to prioritise the “tickets” in the order that he wants them produced to suit flow through his cell.  This was achieved by the cell B supervisor taking control of the order of the tickets at a daily morning meeting and posting these into a load levelling box according to the timeslots when he wants them produced by.  In this way cell B is now pulling the production required.

Practical Application of Kanban – Next Steps

During the next phase we need to persuade the company to produce in smaller batches, and link more closely the flow of work between individual machines in cell A and individual machines in Cell B.

Eventually we should be able to remove the intervention of the supervisor(s)  and get closer cooperation of the Cell B to Cell A machine operators themselves to drive the visual management of the “tickets”.

During most practical applications, whilst we can see what the end game (or future state) looks like, we need to proceed carefully with the people fully involved to avoid overwhelming them with too many changes at once.

Even the relatively simple change to the prioritisation of the “tickets” required three days discussions and workshops, with simulations to demonstrate how the new process would work.

Simulations using sticklebricks or lego are a great way to help people visualise the process.

If you’re interested in how we could help you and your company implement a Kanban process, or want to comment on this case study please contact us – we will also be delighted to receive any thoughts on how we could improve this implementation still further!

We'll do another post soon on a practical implementation for a more complex production system.