Eliminating Variability Through Standardization

Örebro universitet Örebro University

Institutionen för School of Science and Technology naturvetenskap och teknik SE-701 82 Örebro, Sweden

Mechanical Engineering, Degree Project, Advanced Course, 15 Credits

Eliminating variability through standardization

Rasmus Åström, Peter Meyer

Bachelor of Science in Industrial Engineering, 180 credits Bachelor of Science in Mechanical Engineering, 180 credits

Örebro Spring term 2016

Examiner: Lars Pejryd

Abstract

The purpose of this thesis was to review and investigate processes by analyzing what impact logistics and handling had on the transportation units, with the goal of proposing a solution strategy for how to prevent and reduce the breakage of these units.

By creating and applying standards and guidelines, specified in this thesis there is the

opportunity to greatly reduce: cost of costumer claims, ecological impact and risk of injuries To achieve this: mapping of the processes and locating risk factors, archival studies, literature, Ishikawa mapping, a case study and interviews were performed.

With the methods used, two main problem areas were found and investigated. Analyzing these two problem areas lead to the recommendations of standards and application of Standardized work.

Sammanfattning

Syftet med det genomförda examensarbetet var att undersöka och analysera vilka effekter logistik och hantering haft på hållfastheten av lastningsbärare för att ta fram ett

lösningsförslag på hur brott kan förebyggas.

Från införda standarder och riktlinjer, presenterade i det här examensarbetet kan reklamationskostnader, ekologiska kostnader och skaderisker kraftigt minimeras.

Processkartläggning och risk sökning, Arkiv- och litteraturstudier, Ishikawa- kartläggning, fallstudie och intervjuer genomfördes och användes för att få fram resultatet.

Med de använda metoderna kunde två problemområden hittas och undersökas. Analysering av dessa problemområden ledde till en rekommendation om applicering av standardiserat arbete.

Acknowledgement

This thesis was made as a bachelor thesis at Örebro University and was conducted per request of Suzuki Garphyttan. First we would like to thank Suzuki Garphyttan for giving us the trust for taking on this problem and create this thesis, we hope that our findings will come to use and be of help.

We would like to thank our mentor at Suzuki Garphyttan, Malin Johansson for always taking the time to help us in the largest possible extent. We also like to thank everyone at Suzuki Garphyttan who made us feel welcome and has dedicated their time and assisted us with all the facts we needed.

Also our greatest thanks to our mentor at Örebro University, Kerstin Winge for all the coaching and guidance through this thesis.

Terminology

EC-testing - (Eddy Current-Testing) - A process for finding surface flaws, using magnetic current. In this thesis it’s also referred to the physical location where

EC-testing is performed

EC-operator - Operator working with EC-testing

Carrier - Carrier made of welded pipes which carries finished products

High carrier - The carrier in which this thesis have been focused on, which is 48” in Diameter. Used for high ring weights.

Low carrier - Carrier with the same diameter but lower height. Used for medium ring weights.

Small carrier - Carrier with a diameter of 36”, used for small ring weights. Team - Operators working together on the same shift

Ring - Steel wire coiled on carrier

Ring weight - Total weight of wire on one carrier

Coiling - Referred to the process where steel wire is coiled onto the carrier OT - (Oil tempered) - A hardening heat treatment used on steel wire OT department - The department where this thesis has been mainly focused.

Table of contents

2.1.1 Claims from customers ... 11

2.2 The process ... 12

2.3 Previous occurrences by Suzuki Garphyttan ... 13

2.4 Previous occurrences by others ... 13

2.5 Definition of technical area ... 14

2.6 Theoretical framework ... 14 2.6.1 Pareto principle ... 14 2.6.2 FMEA ... 14 2.6.3 Standardized work ... 15 2.6.4 Ishikawa diagram ... 15 2.7 Interviews ... 15 2.8 Case study ... 15 3 METHOD ... 16 3.1 Methodology ... 16 3.2 Observations ... 16 3.3 Ishikawa-diagram ... 16 3.4 Survey ... 16 3.5 Interviews ... 16 3.6 Case study ... 17 3.7 Archival analysis ... 17 3.8 Literature ... 17 4 RESULTS ... 18 4.1 Classification of problems ... 18 4.1.1 Level of severity ... 18 4.1.2 Level of complexity ... 22

4.1.3 Weighting of problem areas ... 23

4.2 Problem analysis ... 24

4.2.1 Breakage from handling ... 25

4.2.2 Unstandardized loading ... 28

4.2.3 Carriers impossible to lift... 31

4.3 Broken carriers are not discarded ... 36

4.3.1 Case study of operators visual control ... 37

4.3.2 Data from the case study ... 39

4.3.3 Results from the case study... 42

4.4 Visualizing results ... 46 5 DISCUSSION ... 47 5.1 Evaluation of results ... 47 5.2 Findings ... 47 5.3 Source criticism ... 47 5.4 Sustainable development ... 48 5.4.1 Economic Sustainability ... 48 5.4.2 Social sustainability ... 48 5.4.3 Ecological sustainability ... 48 5.5 Continued work ... 48 6 CONCLUSIONS... 50 7 REFERENCES ... 51 APPENDICES

A: Form for discarded carrier B: Statistics of discarded carrier C: MSA results

D: Sheet test E: Internet test

Table of figures and tables

Figure 1. An unloaded carrier [Left] A loaded carrier [Right] ... 9

Figure 2. Zoomed in picture of crack on carrier ... 10

Figure 3. Claims concerning broken carriers the last four years ... 11

Figure 4. Flowchart of old and new carriers [3] ... 12

Figure 5. Delivery storage ... 21

Figure 6. Weighting of problem areas ... 23

Figure 7. Ishikawa-diagram with problem areas ... 24

Figure 8. ABC-diagram, Articles 2015 Suzuki Garphyttan, data from archival analysis, OT department ... 26

Figure 9. ABC-diagram, Sales per Costumer 2015 Suzuki Garphyttan, data from archival analysis, OT department ... 27

Figure 10. Ishikawa-diagram focused on forklifts pushing carriers... 28

Figure 11. Forklifts pushing stacked carriers ... 29

Figure 12. Loaded carrier ... 31

Figure 13. Ring weight distribution on largest customer ... 33

Figure 14. Ring weight distribution on second largest customer ... 34

Figure 15. Ishikawa-diagram "Broken carriers are not discarded" ... 36

Figure 16. Time on control check/carrier differs in the span of 9 to 47,6 seconds ... 39

Figure 17. All data from operators’ tests 0=Not OK, 1= OK ... 39

Figure 18. Results from the expert tests ... 40

Figure 19. Results from Ocular test and Sheet test ... 40

Figure 20. Error percentage between operators and experts ... 41

Figure 21. Relation between time and missed cracks ... 42

Figure 22. Ishikawa with visualization of solution ... 46

Table 1. Weight limits of different carriers ... 32

Table 2. Distribution of carriers on largest customer ... 34

Table 3. Distribution of carriers on second largest customer ... 35

Table 4. Costs to return carriers from customers’ location ... 43

Table 5. Statistics of discarded carriers and carriers not sent back ... 43

Table 6. Customer claim costs for 2015 ... 44

Table 7. Cost analysis for discarding carriers, in different stages ... 44

1

Introduction

1.1

The Company

Suzuki Garphyttan (SG) is a world leader in developing and manufacturing advanced steel wire. SG works with oil tempered, carbon steel and stainless steel wire. The company operates in China, Germany, USA, UK and Sweden. Production takes place in the listed countries, except Germany which is a sales office. There are approximately 500 employees working for the company with approximately 350 working in the Garphyttan site. This

particular thesis focused on the oil tempered department in Garphyttan where 125 workers are employed, with 115 working in production.

The company was first formed in 1906 as “Garphytte Fabriks Aktiebolag”. Although the company has been operating for over a century, the focus has not changed from its initial concept. The company has always worked with steel wire and never left its core business. Over the years, it has developed better techniques for production and created newer and more advanced wires.

When the company was bought by Suzuki Metal in 2009, the name was changed to Suzuki Garphyttan. This name was kept when the company was later bought in 2015 by the Japanese Nippon Steel & Sumikin SG Wire Co., Ltd. Group.

Suzuki Garphyttan has a yearly turnover of 800 MSEK. The total of the whole Nippon Steel & Sumikin SG Wire Co., Ltd. Group has a turnover of approximately 305 billion SEK [1]. The main competitors in the steel wire business is Pengg, KIS wire, Suncal and Mubea.

The company is working with lean system production and is continuously striving to improve to lower their emissions even when production volumes are rising. SG works closely with its customers to offer fast deliveries and to provide storage for purchased items. [2]

1.2

The Project

The objective of this thesis was to analyze how the logistics of handling carriers impacts their durability. Durability can be achieved by eliminating the breakage of loaded carriers

throughout the delivery process. This in effect, will in order to decrease carrier damages and reduce claims made by customers. This will also minimize the risk of employee injuries that are caused by broken carriers.

1.2.1 The carrier

Carriers are used to coil as well as store the finished steel wires during transportation and handling. Other carriers are used throughout the process but this thesis focused specifically on delivery carriers, which are used for coiling, storing and delivery. Once the wires have passed through the production process, they are stored and later sent to be delivered to the customer. Transportation of carriers are made by forklift trucks. Lifts with the forklifts are made on the areas illustrated with red arrows in Figure 1.

1.3

Delimitation

This thesis evaluated high carriers as the problem is limited to this carrier model, as it experiences the highest loads. No strength or design calculations were made.

2

Background

2.1

The problem

Broken carriers create a risk for human injuries and can damage products. When the breakage occurs outside of the factory, products are wasted and the products must be re-shipped. The weight that is loaded on this type of carrier is between 1-2 tons. The ring weight has steadily increased and most carriers are now loaded with close to 2 tons. When a loaded carrier breaks, the ring can fall to the floor and get contaminated. If this happens, it can no longer be used and all the wire must be discarded.

Carrier breakage occurs almost solely beside the welded area on the bottom of the carrier which takes on most of the load. If the carrier is lifted, there will be damage, however this can be limited.

The main issues to solve:

 Where in the process does breakage occur?

 What impact do the different parts of the carrier flow have on the durability of carriers?

 How can carrier damage be limited?  What are the main reasons for breakage?  How can breakage be prevented?

2.1.1 Claims from customers

In the last couple of years, claims have increased drastically.

Figure 3. Claims concerning broken carriers the last four years

This diagram is based on data which was exported from Suzuki Garphyttan’s internal database.

Figure 3 show the claims made in the last four years. Note that the claims for 2016 have been tracked until May. It is hypothesized that the main reason for the sudden increase of reports is due to the fact that customers are frustrated by repeated breakage and are now starting to report claims. Last year (2015) there were 11 claims which added up to 570 041 SEK which is roughly 52 000 SEK per broken carrier. Claims are only filed when the wire on the carrier is damaged. If the wire on the carrier can be saved, the customer does not file a claim.

2.2

The process

Carriers are used throughout the delivery process; from coiling before delivery, to uncoiling once the product is delivered. Figure 4 demonstrates how carriers are used.

The carriers are made by a supplier just 20 km away from SG and delivered by truck to SG. After delivery, carriers are moved to the carrier storage. There are two different storages for the carriers including one at the EC-testing site.

Once they are in the storages, the carriers are later moved to one of two wire coiling stations, depending on whether or not the customer is willing to pay for the extra EC-testing. At both stations, the wire is coiled onto the carrier. Before coiling, a brief visual check is made to see if it is in good condition or if it must be discarded. After the carrier is coiled, it is wrapped with shielding plastic and then moved to the delivery storage.

Depending on what customer the wire is to be delivered to, it can be stored from a few days up to a full year. The reason being that some of the biggest customers have an on-call delivery storage with purchased products. When it is time for delivery, the carriers are moved from the storage to the load-out where they are lifted onto the delivery truck and shipped to the

customer.

For the larger customers, SG pays for the carriers to be returned to SG property. The problems

lie in the fact that only few customers actually return the carriers. When carriers are returned to SG, they are stacked 10 by 10, on 11 spots which adds up to 110 carriers per truck. After return delivery, the carriers are either moved to the EC-testing carrier storage or the main carrier storage. Usually the carriers are returned to the EC-testing storage because it is closer to where they are coiled.

Some of the forklift operators perform a visual assessment of the carrier’s condition right after the unloading of returned carriers. The observations made by the operators are very brief and only the cracks on top of the pile are assessed.

2.3

Previous occurrences by Suzuki Garphyttan

In 2015, the company implemented a new way to observe the life-span of carriers. This was done by marking the carriers with “X-XX”, the first X marks the year it was created (A being 2015, B meaning 2016, C meaning 2017, etc...), and the XX marking the month it was created. Although this is not always followed up, it still gives a better idea of the lifespan of carriers. It is more important to know how many deliveries carriers can endure rather than how long a carrier is usable.

At roughly the same time as the date system was introduced, the coating was changed from material made by galvanization to a rust repellent color. This change was made to decrease the cost of the carrier by about 10% and to reduce the use of lead. Galvanization required carriers to be ordered in large batches. When the color coating was added, there were no volume restrictions. Galvanization also required holes to be drilled into the material in order to drain zinc from the carrier, which made the overall material weaker.

(Interview with Jan Andersson, Purchasing Manager, 2016-04-18) KOMMATERING

2.4

Previous occurrences by others

Two years ago (2014) students from Örebro University conducted a FEM (Finite Element Method) analysis on the geometry of the carriers on behalf of the carrier manufacturer. Their aim was to investigate if there was a possibility to increase the strength of the carriers. The research concluded that carriers should be reinforced by doubling the amount of pipes on each leg in order to protect it against breakage on the HAZ (Heat Affected Zone) close to the weld. The results were sound in theory, however when it was practiced, other problems appeared. The new carriers were 20% heavier and were difficult to stack because of the extra pipes. This made it almost impossible to handle the carriers by hand, and therefore handling inventory became less effective. This meant less carriers were sent in each truck and therefore returning carriers from customers was done at a greater cost.

2.5

Definition of technical area

The following fields are related to this thesis. Knowledge in each of these fields is necessary and contributes to the outcome of this thesis:

1. Quality management

2. Operations and process management 3. Lean production

4. Production Technology

5. Some knowledge in economy and financing

6. Some knowledge in Mechanics and Strength of Materials 7. Logistics

2.6

Theoretical framework

The theories presented in this section have contributed in different ways throughout the thesis. Some theories have been applicable in specific cases while others, like Standardized work, Interviews and Ishikawa diagram have been used continuously during the thesis.

2.6.1

According to the Pareto principle, also known as the 80-20 rule, roughly 20% of causes add up to 80% of the effect. This rule was first stated by the Italian economist and statistician Vilfredo Pareto in 1896 and has since been applied to most known fields. He noticed this principle when he saw that 20% of the Italian population owned 80% of all properties [4]. Years later, Joseph M. Juran reviewed Pareto's work and applied it to quality issues and stated “the vital few and useful many” to remark that the lesser 80% should not be ignored. This ideology created the Pareto chart. [5]

According to the Pareto managerial principle, also known as the A, B, C classification, a Pareto diagram can be created with three major categories. These groups are according to the Pareto principle and are used to sum up large amounts of different values into larger classes. This is useful when article groupings are made or if companies need to cut down on article variety to best use their resources.

The different classes are named as A, B & C whereas:

 A stands for highest 20% of the total sum (the vital few)  B stands for the next 30% of the total sum

 C stands for the lesser 50% of the total sum (the useful many) [5] 2.6.2 FMEA

FMEA (Failure Mode and Effect Analysis) is a tool used in “product & production development” to systematically identify different failures or risks.

In an FMEA, several failure components are to be determined and given points depending on:  Probability - how often does the problem occur

 Detection - how easy is the problem to notice

This tool is built on experience, available data and competence by completing the following:  Evaluate every function; what could go wrong?

 Express a solution and change for every failure with a high amount of risk points The sum of the points from the three categories gives a total risk point, which provides an idea of the problem areas. [6]

2.6.3 Standardized work

Standardized work is an agreed way of performing tasks and work. When standardization occurs, all operators work as if they were the same person. When an operator retires, there should be no loss of competence or skill. If operators work in a standardized way, deviations are small and more easily detectable as the human factor of errors is restricted to a minimum. “Standardized work is a tool for developing, confirming, and improving our processes.” [7] Applying standardized work has a great impact on improving processes and methods. Workers should be included in this process because there is often a lot of individual knowledge and tactics that experienced workers have discovered and implemented during their time at the company. [7]

2.6.4

Ishikawa diagram

To visualize and to help find the cause of problems, an Ishikawa-diagram can be used. The diagram, also known as “fishbone-diagram” or “cause and effect diagram” is suitable for solving complex problems. It can be used to divide problems into smaller sub problems, in order to find the different root causes to each and every problem, kind of like Brainstorming [8]. Or as mentioned by John Bank: “This diagram helps the team to separate cause from effect and to see a problem in its totality” [4]. This method is very useful when coping with complex problems. [9]

2.7

Interviews

There are three types of interviews:

 Open - when an interviewed stakeholder leads the conversation but held within the borders of a specific subject

 Semi-structured - when the interview is mixed with fixed questions and an open dialog.

 Structured - when the interview is formed like a survey with specific questions. [10]

2.8

Case study

A case study is an investigative tool used to develop a deeper understanding. Case studies describes the operations and processes of a specific case.

3

Method

The methods used to gather data are presented in this section. These methods include literature and database studies, observations, interviews, surveys, case studies and an

Ishikawa diagram. Collecting data for these methods was done by conducting interviews and by closely observing the internal carrier process.

3.1

Methodology

There are four different methodologies. These include:  Descriptive

 Exploratory  Explanatory  Problem solving

This thesis focuses on identifying problems and finding a solution, which is the definition of a problem solving methodology. [10]

3.2

Observations

Observations were crucial in this process. The observations made were important to gain a broad understanding and a complete picture of the concerning processes as well as the handling of carriers. Observations also helped identify the different problem areas and the causes behind them.

3.3

Ishikawa-diagram

This method was used to divide problems into smaller sub problems, in order to find the different root causes to each and every problem.

3.4

Survey

A survey is useful when a specific investigation is needed. In this thesis, a survey was performed to investigate the amount of discarded carriers. To make a cost analysis possible, there was a need to collect data regarding the amount of carriers discarded each year. This collection took place during 5 consecutive weeks. Notes were handed out to every station on the EC-testing. The operators at the EC-testing were asked to note every carrier they chose to discard. [10]

3.5

Interviews

In order to create a solid understanding of the problem and the processes involved, several interviews were conducted during the start of the thesis.

The interview types used in this thesis were “semi-structured” and “open” forms. The

interviewed stakeholders were all in different positions in the company and they all had some involvement with the concerned process. The stakeholders included managers, engineers, technicians, purchase manager, forklift operators and EC-operators. One external source, the carrier supplier, was also interviewed.

3.6

Case study

In this thesis, a case study was performed to create a greater understanding of the decision making by operators in the carrier evaluation process. The study consisted of an ocular test, test sheet and an expert test where trusted sources were asked to take part in the study.

3.7

Archival analysis

To gather important statistics regarding sales numbers, the database of Suzuki Garphyttan was used. Through this database, information such as relevant data and statistics in regard to sales, amount of claims by customers and article distribution was collected and analyzed.

3.8

Literature

Literature was used as a source to back up theories mentioned in the thesis, which produced a more accurate report. Useful literature was found by searching the university database.

4

Results

Results explain when and for what reasons different decisions are made, and to summarize the reasoning behind the conclusions. This section began with a classification of problem areas, which showed why some areas have been further investigated and why others have not. The problem was later divided into an Ishikawa diagram to visualize the causes and effects as well as finding the root of problems. Each division of the diagram is presented and investigated in this section.

4.1

Classification of problems

To get an understanding of the most important departments and processes in regard to carrier breakage, a classification of problem areas has been made. Different parts of the flowchart have different impacts on the problem. To know which areas to further investigate, the areas have been classified by severity, as well as complexity. These are estimated given points depending on the two categories, and the processes with the highest sums have been prioritized.

4.1.1 Level of severity

The points given in this section are results from observations as well as interviews with stakeholders in the concerned processes.

The signs below were inspired by FMEA. It comprises of colors based on a number from 1-10, 10 being the part of the process that is in most need of change. The level of severity was determined by observations and interviews.

Unknown severity

Green marking is 0-3 Low severity

Orange marking 4-7 Medium severity

Customer -?

This is marked with a question mark because it is unknown how the carriers are handled by the customers. As mentioned, logistics and handling outside of SG are not within the demarcation of this thesis.

Forklift check “OK Carrier?” - 2

The marking on “Forklift check” has been colored green, the mark of “least severe”. This is the first step after the carriers have been returned and unloaded from the truck. Once carriers are unloaded, the forklift operator quickly observes the carriers with the intention of

discarding broken ones. It is hard to evaluate carriers when they are stacked together and therefore, this check is not the main one.

Coiling check “OK Carrier?” – 10

The process “coiling check”, is in between the step” Prepare for coiling” and “Wire coiling”. This step has been given the red marking, the highest grade of severity. The reason for this is because this evaluation determines whether or not a broken carrier is loaded and sent to a customer. No matter how well carriers are handled, the problem will still exist if coiling check is not done appropriately.

Delivery storage – 4

The process “Delivery storage” has been given a yellow triangle of severity. This is due to the fact that the lifespan of a carrier is determined by how and how many times they are lifted. Between coiling and delivery, some carrier could be lifted as much as 10 times (Interview, Forklift operator 2016-04-05). The layout of the storage and the volume of stored products have a large impact on how frequently a carrier is being lifted. The more lifts, the more tension is put on the carrier.

Figure 5. Delivery storage

Prepare delivery – 2

The “Prepare delivery” is marked green. The motivation behind the severity rating is similar to “Delivery storage”, the difference being fewer lifts.

Truck loading – 9

The final step of the process before the carriers are shipped to customers is “truck loading”, which has been given the highest mark of severity. From observations and interviews, it has been noted that pushing of loaded carriers is a frequent occurrence in this process. Because of limited space in the trucks, loaded carriers must be stacked on top of each other before they are lifted onto the truck. If both carriers can’t be lifted together, the forklift will push it up the loading ramp which creates a great amount of tension on the bottom part of the carrier (Phone interview with supplier of carriers, Bengt Olson 2016-04-19).

4.1.2 Level of complexity

To determine the final classification of the problem areas, complexity was rated in the same way as for severity. In this section, points were given to determine the level complexity by the same scale of 1-10, 1 being the highest complexity and 10 being the lowest.

Customer -?

Not within the demarcation.

Forklift check “Ok Carrier?” – 5

The forklift check has been given a medium complexity level. It involves management and standardization. With clear instructions to remove noticeably broken carriers, the complexity is not of a high level. The point for complexity had to be lowered because this procedure was already followed, which makes it hard to improve.

Coiling check “Ok Carrier?” – 7

Coiling check has been given a point slightly over medium. The reason for this, is that the problem could be solved by following guidelines for the carrier evaluation. There were no guidelines at the start of the thesis.

Delivery storage – 2

Delivery storage has a high complexity level and therefore was given a low complexity point. Since the storage contains a large volume of products, a lot of effort and costs are involved in any restructure or volume changes.

Prepare delivery – 2

Because of the storage being the main reason for the amount of lifts, not a lot can be

improved on “prepare delivery”. Delivery preparations are made by the forklift operators and from observations, no possible improvements could be found. Therefore, this division has been given a low complexity point.

Truck loading – 5

Truck loading is complex to rate. The reason for this will later be explained under

“unstandardized loading” as the effect of the solutions could not be determined to the full extent before it has been applied. Therefore, the section has been given a medium rating. 4.1.3 Weighting of problem areas

When the total score of complexity and severity was added up, the product gave the total scores used in weighting the different sections. The highest sum assumed the highest priority, highest priority being 1 and lowest 5.

Figure 6. Weighting of problem areas

Priority 1-3 were further investigated and priority 4-5 were discarded. 1-3 were chosen because of their high level of severity, mixed with low complexity, making them the ones that provide maximum impact with the least amount of effort. According to the Pareto Principle, a few causes and small improvement can have large effects on the outcome [11]. [6]

4.2

Problem analysis

Figure 7 shows an Ishikawa-diagram that was created to analyze the main problem of “broken carriers” and divide it to several sub problems. This is used to find the root causes of the problem and to search for the best solutions.

In this Ishikawa-diagram, sub problems outside the demarcation are presented, but will later be excluded. Every “bone” on the diagram will be investigated and presented. The sub problems which are not further examined will be presented with a motivation for the exclusion.

4.2.1

This leg has two causes connected to it; “unnecessary lifts” and “forklift damage”. Both of these causes are presented and analyzed in this section, as well as the causes and effects related to them.

4.2.1.1 Unnecessary lifts - Storage layout

Optimizing the storage layout would lead to fewer lifts and therefore would lead to less gradual damage on the carriers.

This leg on the Ishikawa diagram has only one leg connected to it, which is why both causes have been combined into one category. The two causes behind the storage layout is article volumes and article grouping, both of which are presented in this section.

4.2.1.1.1 Article grouping

Articles in a storage layout are either randomly assembled, grouped together or categorized by similarities and relations. Grouping can be made in account to article weight or dimensions, it can also be made by grouping articles depending on their destination.

To find the optimal storage layout, deciding on article grouping is important. Two principles should be taken into account when deciding which articles are to be grouped together, Principle of Popularity” and “Principle of Similarity”. Both of these principles have been applied in this thesis. ABC diagrams are presented in this section, both for articles as well as customers. If one of the two categories have a spread much larger than the other, according to the principle, it should be the optimal storage layout. If the spread in both ABC diagrams are similar, the principle of similarity should be accounted for as well. [12]

4.2.1.1.1.1 Principle of Popularity

When applying the principle of popularity, articles are grouped depending on their popularity i.e. how frequently they’re sold and shipped. This was made with the help of Pareto’s ABC diagram.

To investigate whether grouping by articles or by customers is best suited in the principle of popularity, Pareto charts were created Figure 8 & Figure 9. Figure 8 is used to visualize the total spread and distribution of all the articles stored and sold by Suzuki Garphyttan.

Figure 8. ABC-diagram, Articles 2015 Suzuki Garphyttan, data from archival analysis, OT department

Figure 8 displays article variety as well as sales distribution, using Pareto’s ABC- diagram. In total, 479 units of different articles were produced last year (2015). Total sales on these articles were 17067 units. Figure 8 shows that group A, which is the group consisting of the 20% most sold articles, adds up to a total of 73% of the total sales. Group B, the second staple consisting of 30%, stands for 22%. The smallest and least frequent group C, sold 50% of total variety, which accounted for only 5% of the total units sold.

From Figure 8, the ABC principle is indeed applicable. The principle can be used in different ways for variable reasons. For companies with limited production capacity, this principle can be used to decide which articles to keep and which to eliminate. As previously mentioned, in this case, it is used in regard to article grouping. Following the ABC principle, A articles would be stored close to the loading station whereas C articles would be stored further away. [11]

Figure 9. ABC-diagram, Sales per Costumer 2015 Suzuki Garphyttan, data from archival analysis, OT department

Figure 9 shows that group A, the largest customers, account for a total of 71% of the total sales, whereas the next 30%, group B, totals 22%. The smallest 50% of the customers, group C, only stands for a rough 7%. With this distribution of sales in regard to customers, ABC principle can be used for dividing storage areas with A customers closest to the loading area. [11]

4.2.1.1.1.2 Principle of similarity

The principle of similarity dictates that articles which are shipped together should be grouped together [12]. As customers never share a truck, articles that are shipped together are bought by the same customer.

4.2.1.1.1.3 Conclusion from applied principles

Some of the larger customers, which are in the “A” group, have specific storage areas assigned to them. These customers also have an on-call delivery agreement with SG.

Looking only at the principle of popularity, both article grouping and customer grouping are close in comparison because. However, when the principle of similarity is brought into account, customer grouping implies to be a more suitable storage structure. [12]

4.2.1.1.2 High volumes

Unnecessary lifts are not just a product of an un-optimized layout; it is also a product of high inventory. With a lot of inventory, more products must be stacked on top of each other. Because of this, more products must be moved to be able to reach a specific carrier. This causes lifts to be made more frequently which would gradually damage the carriers. A solution to this problem was already in the process of being carried out. The company is planning to move large parts of their on-call storage to Germany to keep it closer to their main

customers and to create space in the factory. This is the reason why no further study was made in the category.

4.2.1.2 Forklifts damage- Pushing loaded carriers

A smaller version of the Ishikawa diagram is presented Figure 10 to highlight and analyze the root causes for pushing carriers onto the trucks and to find a solution for how it can be

prevented.

Figure 10 demonstrates the results of interviews as well as observations. Both legs in the Ishikawa diagram are analyzed and presented in this section.

Figure 10. Ishikawa-diagram focused on forklifts pushing carriers

4.2.2 Unstandardized loading

For developing an understanding of the loading process and its impact on the durability of carriers, several measures have been taken. Interviews were held with a technician, the supplier of carriers and with most of the operators in the process. Observations were also made on several occasions to get an understanding of the differences and similarities between

operators and between the teams.

From an interview held with technician Mika Hynninen (2015-04-18), attention was brought to the fact that carriers were being pushed by forklift operators. This did not represent the full extent of the problem as the interview was about carriers being pushed a few decimeters after they have been loaded onto the truck.

An interview regarding the consequences from this type of loading was held with Bengt Olson, CEO of Örebro Svets which is the supplier of carriers (2015-04-19). According to him, carriers are not supposed to be pushed. Even if carriers are on flat ground, unloaded, there is still a big risk for deformation. With loaded carriers, the amount of force needed to overcome the frictional force against the ground, is very close, maybe ever larger than the force needed to deform a carrier.

When forklift operators were asked on how often carriers are being pushed, the answers differed between the teams. One major difference was exposed when some claimed it happens once or twice a month while others said several times a day. (04-21, 04-22, 2015-05-09)

From observations as well as interviews with forklift operators, two different loading processes could be mapped.

4.2.2.1.1.1 Loading process for two thirds of the forklift teams

1. An operator picks up a carrier from the storage 2. The loaded carrier is placed by the ramp

3. The operator picks up another carrier from the storage 4. The loaded carrier is placed on top of the other carrier

5. Both carriers are pushed up the ramp onto the truck

From interviews with the operators working according to the steps above, pushing carriers is a necessary method to get the carriers onto the truck.

The reasons being:

1. Height of the truck roof is too low for a carrier to be stacked on another carrier while on the truck.

2. The wire is coiled too high on the carrier which prevented the forks from being able to grab two carriers at the same time.

Note that operators in one of the teams found a way to overcome the second reason listed above.

4.2.2.1.1.2 Loading process for one third of the forklift teams

1. An operator picks up a carrier from the storage 2. The loaded carrier is placed using a ramp

3. The operator picks up another carrier from the storage 4. The loaded carrier is placed on top of the other carrier

5. An operator picks up a small loaded carrier and uses it to compress the ring on the top carrier so the height of the ring becomes small enough for the forks to be able to reach the carrier underneath, and the ring gets wider.

6. Both loaded carriers are lifted at the same time and do not need to be pushed up the ramp.

The operators working according to the steps above created the procedure themselves.

Because of this, pushing carriers was only a necessity once to twice a month. This would be a big improvement if the method was spread to the other teams as well. When good methods and problem solving’s have not been applied by all operators, it is a strong indication of a lack of standardization.

Stacked carriers are coiled with very large coil weights which makes it impossible to lift both at the same time.

Competence exists within one team however their approach has not been shared with all the teams or enforced by the leadership. The leadership has not been working with

standardization in the process and therefore strategies have not been shared and methods have not been standardized.

4.2.3 Carriers impossible to lift

If all teams worked similarly to the optimal team mentioned above, the improvement would be substantial. Although it would not solve the problem all together as there are some cases where no other option works except for pushing the carriers up the ramp. Although this is a rare occasion and occurs only once or twice a month, it still needs to be examined if it can be prevented.

The reason why pushing is the only option, is because two high-coiled carriers stacked on top of each other makes the top ring block the pipes so the forks on the forklift can’t reach the lower carrier. This results in the forklift being unable to lift both carriers at the same time. According to the forklift operators, this problem can be solved in two ways; ring height and order structure. Both options are presented in the Ishikawa diagram.

Figure 12. Loaded carrier 4.2.3.1 Coiled too high

Height settings for the rings are made by the EC (Eddy Current)- operators on the EC-machines, where the carriers are coiled and the steel wire is tested.

The weight of the ring is already set when an operator receives a request and before the coiling has started. With the requested ring weight, the operator decides the ring dimensions (height and width) in order to match the requested ring weight.

There are no standards regarding maximum height or maximum width. The operator decides the dimensions which he/she sees fit. From interviews with EC operators, a big factor that the operators take into account when deciding on the dimensions is that they do not want the ring to be too wide as it makes it more difficult to apply the wrapping around the ring. (Interviews

with operators, 2016-05)

Standardized processes reduce variability on outcomes, which is the result of personal preferences. Standardization comes in effect when specific measurements are developed and applied. Standardized measurements can be calculated by measuring the ring height for which carriers can no longer be lifted two at once. According to lean, it is vital to invite the operators to be a part of this process and the changes that will be made. It is also important for the EC operators to give their input on how the maximum ring height could affect their work when the bags are wrapped around the ring.

4.2.3.2 Impact from order structure

How often two high carriers must be loaded together depends on how the orders are structured. If high ring weights can be mixed with low ring weights, it could reduce the frequency of the problem of the carriers being pushed. This is because it is easier to lift a low and a high carrier together than it is to lift two high carriers at once (Observations and

interviews with forklift operators).

There are 11 spots for carriers in one truck. This means that if 12 high carriers are to be loaded in a truck, two high carriers must be loaded together. If the majority of shipped carriers are high carriers, they will still have to be stacked together and a restructure would be

ineffective. By distributing high carriers so that most trucks are sent with no more than 11 high carriers, pushing would not be necessary.

There are no available statistics on how often trucks are loaded with 12 or more high carriers. To get an estimation of how often this occurs, the total amount of sent out carriers were studied. As no data was available in regard to this, data on ring weights was used.

Carriers were chosen depending on the ring weight, although this was not defined on exact limits. The same ring weight might be coiled onto different carriers but the following approximations still gave reliable results.

Table 1. Weight limits of different carriers

Ring weight Carriers

< 850 kg 36”

850-1200 kg 48” low

The two largest customers that account for more than half of the yearly sales have been studied. These two customers were chosen because their sales numbers were high and their deliveries were frequently made with full trucks. Full trucks equivalents to carriers being

stacked on top of each other and this is where the restructure would be most effective. If a truck is shipping 8 carriers to a customer, the distribution of high ring weights i.e. high carriers, would have no effect.

In Figure 13 the limits from Table 1have been applied as Upper Specified Limit (USL) and Lower Specified Limit (LSL). By using these limits, the distribution of carriers could be presented as in Figure 13. The big peak of the graph is very close to the maximum weight limit per carrier.

Table 2. Distribution of carriers on largest customer

Carriers Distribution

36” 16,05 %

42” low 12,02 %

42” high 71,93 %

For the largest and most valuable customer to the company, high ring weights were frequently ordered and the vast majority of used carriers were high carriers [Figure 14].

Table 3. Distribution of carriers on second largest customer

Carriers Distribution

36” 22,85 %

48” low 21,38 %

48” high 55,77 %

The average ring weight and the use of high carriers were significantly lower for the second largest customer, as seen on Figure 16. Still, the majority of delivered carrier were high carriers Table 3.

Restructuring orders does not solve the problem of pushing carriers. At most, it can reduce the frequency of this particular issue. Restructuring orders is unsuitable if demand for high

carriers is too high, as this would not limit the frequency of double stacked high carriers.

From the data presented on both customers, high coil weights had too high of a demand for a restructure of order placement in order for it to be effective.

4.3

Broken carriers are not discarded

In this section, a case study is presented with the included parts and investigated sub problems presented in the Ishikawa diagram. An MSA analysis and a cost analysis is also presented.

4.3.1

A case study was made to analyze the sub problem “Broken carriers are not discarded”. In this section, all causes from Figure 15 except for “Cost to discard carrier is too high” will be presented. The one cause, not included in this section will be covered in the next section “Cost analysis”.

4.3.1.1 Test & purpose

A test was conducted to identify deviations in the visual control routine, between different operators working at the EC-testing station. In this test, 12 out of 13 operators took part. One operator was not included in the test, as this operator was only working night shifts.

The operators included in the test were informed on how the test was going to be conducted. One by one, the operators conducted the test. The time between the tests was short in order to limit talking to prevent influenced results. The operators were asked to complete the test as they would in their day to day routine and to not be more or less meticulous, to get an accurate result.

The case study was conducted in three parts. First was an ocular test, second was a sheet test for operators working with pre coiling control and the third was made with experts in cracks and carriers in order to compare the results of the operators and to help set a standard.

4.3.1.2 Ocular inspection of carriers- test

The first test was to perform an ocular inspection of ten different carriers. These different carriers were pre-chosen and were of variable quality. The test was timed without the

operators’ knowledge. This was done to remove any feeling of pressure or stress and to make the test as reality-based as possible. The reason for measuring the time it took for each operator was to examine the average time on a regular control check and to study if time was a factor of errors. Operators were told to judge these different carriers by “OK” or “NOT OK” to be used, which is how the discard routine works. The different carriers were numbered from 1-10. Operators started with number 1 and ended with number 10 in numerical order.

4.3.1.3 Sheet test of carrier cracks

The second test consisted of the same carriers as in the first test, with the main difference of how the carriers were presented to the operators. In the “Sheet test” the operators rated carriers in the same order as the ocular test but with “OK” or “NOT OK”. Instead of looking at the whole carrier, they were looking on photos of the welded areas and rated the crack sizes.

The reason for why the welded areas were the focal point of this test was because it is the most pressurized point and where most of the cracks occur.

As previously mentioned, the carriers included in this test were the same as in the earlier one, in the same order however, the operators were not informed of this. The reason to have two different tests consisting of the same carriers were to examine the level of consistency in their means of judging.

4.3.1.4 Sheet test of carrier cracks, with experts

To get an understanding of the different severity levels of cracks and where the limit should be set, experts were asked to perform a test.

The experts in this study were Bengt Olson (CEO of Örebro Svets, supplier of carriers) as well as Jörgen (Laboratory technician, specialized on cracks, Suzuki Garphyttan).

Both experts were, on different locations and different times, given the same test as the operators but with several extra images to evaluate. After the test forms Appendix E were completed, interviews were held in regard to cracks and how standards should be set.

4.3.2

The results from the case study are presented and explained in this section. The section starts by presenting all collected data from the studies done with the help of the operators and then present the results from the expert tests. All data have been analyzed and compared, to lead up to the root causes of why broken carrier have not been discarded.

Figure 16. Time on control check/carrier differs in the span of 9 to 47,6 seconds

The expert test Figure 18 required the two independent sources to answer on a form and the

result ended up identical on all questions, which give the results a high level of credibility. Except for the test created for the operators, the experts were asked to rate 8 other pictures of cracks in the Heat affected zone. On all those questions, the experts’ answers were identical. From interviews with the experts they shared their thoughts of evaluation. Transverse cracks (cracks going not with the direction of the pipe but through it) are the ones with the absolute highest risk of total breakage. When a transverse crack is noticed, it should be discarded. This because torque is created when it’s either lifted or pushed and all the torque force will be taken up in the crack and the risk of breakage increase exponentially. (Interview with Jörgen, Laboratory technician at Suzuki Garphyttan)

When studying the results from both tests Figure 19, variability is high between the operators and lack of standards are clear.

Figure 18. Results from the expert tests

The desired values in Figure 19 would be 0% or 100% as this would mean that all operators agreed on the carriers studied being either OK or NOT OK. As for instance, Carrier 1 showed in Figure 19 is on 100% which means that all operators agreed on this one being OK.

By comparing the results from the expert test Figure 18 with the results from The Ocular- and sheet test Figure 19. Errors could be measured and visualized Figure 20.

As seen in Figure 20, the total error percentage range from 0 to more than 40%. Half of the carriers show error rates on more than 30%.

4.3.3

After confirmation that errors exist, the causes for errors had to be studied. From Ishikawa diagram Figure 15, two main reasons for errors were presented. These reasons were “Missed cracks” and “Cracks are considered OK”. In this section, both these effects are presented and analyzed by correlations as well as using MSA (Measurement System Analysis) to investigate the underlying causes.

Figure 21. Relation between time and missed cracks

In Figure 21 the data from the ocular test Figure 17 is compared to the data from the expert test Figure 18. This to study if a correlation exists between time spent per carrier and the amount of missed cracks. There is another type of error, discarding of “good” carrier, which is not included in this figure.

The study did not show any strong correlations between the time spent on evaluation and missed cracks. Therefore “lack of time spent per carrier” has been ruled out as a factor behind missed cracks. This indicate that more time spent on control checks would not reduce variability, although it should be noted that large time deviations between operators is a sign for unclear standards.

From the average of all three teams [Appendix C], the results from the MSA show: error rates, mixed ratings and which type of errors have been made are presented below.

Overall error rate: 21,7% OK rated NOT OK: 23,6% NOT OK rated OK: 18,8% Mixed rating: 25%

The percentages presented above are results from both the ocular tests as well as the sheet tests. These results have been compared to the expert tests which have been referred to as the correct answers. “Mixed rating” show the percentage of operators who have rated the same carrier differently on the two tests.

With the help of MSA it is shown that “NOT OK rated OK” is a less frequent occurrence than the counterpart “OK rated NOT OK”. If the root cause of the concerned problem was “missed cracks”, the case would have been the other way around. All results from the MSA are close to 20% and the high numbers show clear indication of lack of guidelines in the process. This because no number is significantly higher or lower, in relation to the other three categories.

4.3.4 Cost analysis of discarding carriers

To investigate the leg in the Ishikawa diagram presented in Figure 15 “Cost to discard carrier is too high”, a cost analysis was made and is presented in this section. The numbers are from an interview held with Jan Andersson (Purchasing Manager, 2016-04-18) except for the amount of discarded carriers, which are based on the survey, mentioned earlier.

Table 4. Costs to return carriers from customers’ location

The total cost to return a truck loaded with carriers is 35.000 SEK. The truck can fit a total of 140 carriers which add up to a cost of 250 SEK.

From the conducted survey [Appendix A], weekly results could be presented [Appendix B] which were used in Table 5. Last year (2015), 800 high carriers were purchased (Interview with Jan Andersson, 2016-04-18), by withdrawing the amount of discarded carriers the result show that 426 carriers are not sent back by customers.

From archival analysis, costs of customer claims have been presented in Table 6. Average cost per claim 2015 was almost 52 thousand SEK and the total cost for the year ended up to 570 thousand SEK.

In Table 7, all known costs related to discarding carriers are accounted for. The left side show the value decrease of a carrier for each time it has been returned. This is because a quarter of the total value of a carrier is included in the price to customers. On the right side of Table 7, the value is compared to the return costs as well as the refund received from discarding the carrier. The analysis show the percentage saved from scraping a carrier before it’s been sent out and returned, provided that the carrier would be in bad enough shape when it is returned, that it must be discarded.

Table 6. Customer claim costs for 2015

Table 8. Total discarding cost per year

Table 8 show the cost to discard carriers, on a one-year span. The two costs are based on Table 7, where both costs are in reference to a carrier having been sent out twice. Upper row in Table 8 represent the total costs if carriers are discarded at this stage while the second row represent carriers being discarded after return delivery.

From the cost analysis it has been shown that it can be more cost efficient to discard a carrier than to let it be coiled and delivered. This because of the high cost to return carriers from customers’ location. If all carriers were discarded after having been sent out twice, the total cost would be less than a third of last year’s claim costs. With this, “Cost to discard carriers is too high” from Figure 15 should not be considered a factor.

4.4

Visualizing results

This Ishikawa diagram visualize the outcome of the results.

Red lines - Causes which have been eliminated with specified motivations. Green lines - Causes which were used in the presented solution

Blue line - Cause not included in solution, but provided with recommendations on Further investigation.

5

Discussion

5.1

Evaluation of results

In this segment an evaluation of the results was performed. The reason was to discuss the different conclusions and assumptions made in the report and evaluate how credible they were. This evaluation has been divided into two sections; Findings and Source criticism.

5.2

Findings

To conduct this report, several result findings were needed. These different results came from observations, archive analysis as well as statistical collection and a case study.

The statistics concerning discarded carriers could cause deviation because the human factor may affect the accuracy of the results and because of the limited extension of the

investigation.

These statistics were created by involving every operator that was involved in maneuvering the forklifts and in EC-control. With high participation, this collection of data will lead to an accurate result making it much more credible than roughly estimated numbers.

In this thesis, sharing and applying methods concerning truck loading has been recommended. Though this is most likely a step in the right direction, it is not a guarantee that breakage from handling would be eliminated completely. However, this would be a good solution

considering it is cost and time efficient. It should be noted, that observations have been made where even a small carrier on top of a large one required pushing. This is why it is important not only to spread the methods and apply the standards but also to inform of implications in regard to the problem and the importance of a followed standard.

5.3

Source criticism

Most of the sources in this thesis came from interviews and observations, although literature and scientific reports and articles have been studied.

The methods and theories adapted from books and articles may become outdated, and newer and more suitable tools may be created, which could alter the results. The sources have been critically reviewed and the results should be considered credible.

Observations have been a vital part of this thesis, some findings made by observation may alter the behavior of those being monitored, which is known as the Hawthorne effect [13,9]. As the problem has been highlighted concerning the discarding process and this there is a chance that the amount of discarded carriers increased during the time the statistical collection were performed.

It might be considered of value to investigate the opportunity to put “one time use” - carriers to use but in this thesis, this has been seen as outside the delimitation considering it concerns the construction. Implementation of disposable carriers would also decrease the processes ecological sustainability. Disposable carriers would also decrease the processes ecological sustainability.

5.4

Sustainable development

In this part of the discussion the solutions impact on the sustainable development be discussed concerning Economic, Social & Ecological aspects.

5.4.1 Economic Sustainability

Seeing that the proposed solution concerning the control of the carriers is to change the limits and guidelines of what is OK and the new standard in regard to this, will have economic impacts. With the help of the MSA it was found that the error of discarding “OK” carriers were a more frequent error than the error of not discarding “NOT OK” carriers. This means that new costs from the new guidelines, will be compensated with economic gains as well. 5.4.2 Social sustainability

To create an opportunity for the individual person and put them in focus is what social sustainability is about. Applying standards contributes to affinity and a feeling that you are doing something of value, something meaningful. The whole concept with it is to put the operators in focus and let them participate in creating the working standards by themselves. Standardized work would also contribute to a decrease risk of injuries and would make the workplace safer and also creating a platform for continuous improvement.

5.4.3 Ecological sustainability

The ecological aspect has in the last couple of years increased in importance, seeing the need for ecological sustainability becomes more and more important.

As mentioned in Economic sustainability 5.4.1. the new standard does not just increase the amount of discarded carriers; it also decreases the amount of unnecessary discarding, which has a positive effect in regard to ecological sustainability. More importantly, a decreased risk of coiled wire damage and a decrease of customer claims has the possibility to save tons of unnecessary waste as well of unnecessary production. When steel wire is wasted, the ecological cost is not only the material loss, but the whole production needed to replace it. It might be considered of value to look into the opportunity to put disposable- carriers but in this thesis this has been seen as outside the demarcation considering it concerns the

construction. Implementation of disposable- carriers would also decrease the processes ecological sustainability. [14]

5.5

Continued work

To get the best possible limit used in the guidelines in regard to the evaluation process, tensile tests should be made to get a better understanding of the breaking limits of different cracks. With the tests, a new more accurate set of rules can be applied. The new standards mentioned in this thesis should be applied and followed up with operators in the concerning processes and height limits on coiling should be investigated and evaluated to see if it can be applicable to the coiling process and include all consequences in both the coiling process as well as the loading process. This is why the operators must be included in applying new standards.

A carrier should not be discarded solely because of the HAZ (Heat Affected Zone) conditions. The inspection and discarding should also include the general condition, such as if it is bent or broken at other spots than the HAZ. To achieve the standardized work, all the stakeholders engaged in the process should be involved. Standardized work is about involving workers, and it is a keystone in Lean production. To have a bigger impact the worker's thoughts and ideas should always be considered as valuable assets in the process of applying standards.

6

Conclusions

In all areas where solutions are presented, standardization is part of the solution. Two changes should be immediately applied and a third should be further investigated

1. Guidelines for the evaluation process of carriers should be set, to limit the amount of broken carriers passing through the process. From the tests with experts in this thesis as well as the interviews, a guideline of zero tolerance concerning transverse cracks is recommended. Even if the company will plan to make the tensile tests mentioned under “Discussion”, this guideline should be set immediately and replaced later. This should lead to a great decrease of the variability of the state at which carriers are coiled.

2. Standardization in the loading process would greatly decrease the damage taken on carriers and with that decrease the amount of broken carriers. The available

competencies and methods within the workforce, should be shared and made standards. This is an important step when working with lean production. 3. Standards in coiling dimensions should be investigated to further minimize the

occurrence of carriers being pushed and therefore carriers taken damage. Standardized working in the mentioned processes should lead to smaller to a significant decrease of carrier breakage and with the greatly reduce the cost of costumer claims, ecological impact and the risk of injuries, at the same time as an increase in customer satisfaction due to easier handling of the products.

7

References

[1] Allabolag.se. Suzuki Garphyttan AB. 2016; Available at:

http://www.allabolag.se/5560302886/Suzuki_Garphyttan_AB. Accessed 2016-05-13, 2016. [2] Suzuki Garphyttan. About us. 2016; Available at:

http://www.suzuki-garphyttan.com/sg/global/About-us. Accessed 2016-05-13, 2016.

[3] Madison D. Process mapping, process improvement, and process management: a practical guide for enhancing work and information flow. : Paton Professional; 2005.

[4] Bank J. The essence of total quality management. 2.th ed. London: Financial Times/Prentice Hall; 2000

[5] Grosfeld-Nir A; Ronen B;Kozlovsky N. The Pareto mangerical principle: when does it apply?. International Journal of Production Research. 2007;45(10):2317-2325

[6] Britsman C, Lönnqvist Å, Ottosson SO, Tobiasson H, Sveriges verkstadsindustrier.

Handbok i FMEA: failure mode and effect analysis. Stockholm: Sveriges verkstadsindustrier; 1993.

[7] Dennis P. Lean production simplified: a plain-language guide to the world's most powerful production system. New York: Productivity Press; 2002.

[8] Oxford reference, “brainstorming”. Oxford University Press, 2011.Available at:

http://www.oxfordreference.com/view/10.1093/acref/9780199590230.001.0001/acref-9780199590230-e-0192 2016-05-28, 2016.

[9] Bergman B, Klefsjö B. Kvalitet från behov till användning. 5., uppdaterade och utök. uppl. ed. Lund: Studentlitteratur; 2012.

[10] Höst M, Regnell B, Runeson P. Att genomföra examensarbete. Lund: Studentlitteratur; 2006.

[11] Slack N. Operations and process management: principles and practice for strategic impact. 3.th ed. Harlow: Pearson Education; 2012.

[12] Nylander M, Arndt V, Andreasson, Per. Storage Layout at Kalmar Industries in Lidhult -Improved usage of the outdoor storage area, thereby a more efficient material flow [Master Thesis].Göteborg; Göteborg University. School of Business, Economics and Law; 2004 [cited 2016 Jun 8]. Available from: http://hdl.handle.net/2077/2329

[13] Oxford reference, “Hawthorne effect”. Oxford University Press, 2016.Available at:

http://www.oxfordreference.com/view/10.1093/acref/9780199657681.001.0001/acref-9780199657681-e-3697# 2016-06-05, 2016.

[14] KTH Royal Institute of Techonology , Hållbar utveckling. 2015; Available at:

https://www.kth.se/om/miljo-hallbar-utveckling/utbildning-miljo-hallbar-utveckling/verktygslada/sustainable-development/hallbar-utveckling-1.350579

Appendix A: Form for discarded carrier

Skadade knektar

Var god dra ett streck för varje knekt som DU

väljer att sålla bort pga. skada såsom t.ex.

spricka, böjning eller knäckning. Markera då

dessa med dem inplastade röda lapparna.

Detta gäller endast 2 tons knektarna

Vid frågor Ring 076-******* eller 076-*******. Med vänliga hälsningar

Rasmus & Peter

Förmiddagsskift

Eftermiddagsskift

Appendix C: MSA results

[Team 1]

[Team 3]

[Team 2]