Developing a new production concept for High Pressure Hydraulic Hose Assembly
Carl Cederqvist
Mechanical Engineering, master's level 2017
Luleå University of Technology
Department of Engineering Sciences and Mathematics
Acknowledgement
This report is the result of a master thesis performed for Luleå Technical University, in the department of manufacturing engineering. The master thesis focuses on developing a new
production concept for Ultra High Pressure Hose Assemblies to reduce lead-time, reduce production cost and increase production capacity. The master thesis has been performed in Troisdorf, Germany for the company CEJN Product Gmbh. I would like to thank my examiner, Torbjörn Illar, for his support. I would also like to thank my mentor at CEJN AB, John Woollett, the managing director of CEJN Product Gmbh, Klaus Behr and Controller at CEJN AB, Anders Söderström for continuous support and help.
2017-06-08
Carl Cederqvist
Abstract
With a globalized and interconnected world with rapid development in logistics and transport infrastructure, companies are more and more centralizing their business to achieve scale advantages in production and administration. With an increasing global competition comes a growth in the demand for increased productivity and service quality. This creates a need for organizations to have a cost effective production with high flexibility to offer low lead-times and cost competitive solutions.
Due to a more globalized world, CEJN AB predicts an increased competition in the future and want with this project withstand future competition.
This master thesis is focused on improving CEJN ABs High Pressure Hose assembly production in Troisdorf, Germany, in order to become more competitive and to withstand future competition.
The master thesis scope is focused on reducing the hose assembly production cost with 20 %, increase production capacity for a potential centralization of European production and reduce lead- time for the hose assemblies to be able to deliver the same day.
The master thesis is founded on literature review and empirical results achieved through a case study. The case study consists of a current state investigation, situation analysis, concept generation and concept choice. The situation analysis consist of a product range analysis, production process analysis, production cost analysis and a production layout analysis.
The results from the master thesis will improve the production process, reduce lead times, reduce production cost and increase production capacity. The results have been achieved by improving productions processes through an increased automation, introduction of lean thinking and reduction of waste. By implementing the proposed layout solutions, the production time will be reduced, through minimization in material handling processes, transportation times and a better material flow.
The projects outcome will result in a more flexible production with a reduction in set up times and improved working conditions by increased safety and reduction of heavy working processes.
Keywords: CEJN Product Gmbh, Hose Assembly Production, Non-added value processes, Production layout, Lead-time, Production Capacity, Manual Assembly, Set Up.
Sammanfattning
Med en globaliserad och sammankopplad värld med snabb utveckling inom logistik och
transportinfrastruktur, så måste företag mer och mer centralisera sin verksamhet för att uppnå skalfördelar inom produktion och administration. Med en ökande global konkurrens så kommer kraven att öka på produktivitet och servicekvalitet. Detta skapar ett behov för organisationer att ha en kostnadseffektiv produktion med hög flexibilitet för att erbjuda låga ledtider och
kostnadseffektiva lösningar.
På grund av en mer globaliserad värld förutspår CEJN AB en ökad konkurrens i framtiden och vill med detta projekt motstå den framtida konkurrensen.
Detta projekt fokuserar på att förbättra CEJN ABs slangmontage-produktion i Troisdorf, Tyskland, för att bli mer konkurrenskraftig och kunna motstå framtida konkurrens. Huvudprojektet är inriktat på att minska produktionskostnaden med 20%, öka produktionskapaciteten för en eventuell
centralisering av den europeiska produktionen samt minska ledtiden för slangmontage för att kunna leverera samma dag.
Examensarbetet bygger på en litteraturstudie och empiriska resultat uppnådda genom en fallstudie.
Fallstudien består av en nuvarande tillståndsundersökning, situationsanalys, konceptgenerering och konceptval. Situationsanalysen består av en produktsortimentanalys, produktionsprocessanalys, produktionskostnadsanalys och en produktionslayoutanalys.
Resultaten från projektet kommer att förbättra produktionsprocessen, minska ledtiderna, minska produktionskostnaderna samt öka produktionskapaciteten. Resultaten har uppnåtts genom att förbättra produktionsprocesserna genom ökad automation, introduktion av lean-tänkande och minskning av slöserier. Genom att implementera de föreslagna layoutlösningarna reduceras produktionstiden genom minimering av materialhanteringsprocesser, transporttider och bättre materialflöde.
Projektutfallet kommer att resultera i en mer flexibel produktion med minskade ställtider och förbättrade arbetsförhållanden genom ökad säkerhet och minskning av tunga arbetsprocesser.
Nyckelord: CEJN Product Gmbh, slangmontering, Icke värdeskapande processer, produktionslayout, ledtid, produktionskapacitet, manuell montering, ställ-tider.
Table of Contents
1 Introduction ... 1
1.1 Background ... 1
1.2 Objectives and Aim ... 2
1.3 The Thesis Scope ... 2
2 Context ... 3
2.1 The Company ... 3
2.1 The Production facility In Germany ... 3
2.2 The Hose Assembly ... 3
3 Theoretical Framework ... 7
3.1 Lean Production ... 7
3.1.1 Identifying Waste ... 7
3.1.2 Batch size effects and Just-In-Time production ... 8
3.2 Material Supply ... 8
3.2.1 Manual Picking ... 8
3.2.2 Feeding policies ... 8
3.3 Workers health ... 9
3.4 Layout ... 10
3.4.1 Choice of layout type ... 10
3.4.2 U-shaped assembly lines ... 11
3.5 Workers involvement ... 11
3.6 Automation in Assembly lines ... 11
4 Methodology ... 13
4.1 Scope of work ... 13
4.2 Project procedure ... 13
4.3 Project methods and tools ... 14
4.3.1 Data collection methods ... 14
4.3.2 Tools and Methods ... 15
4.3.3 Limitations ... 16
5 Current Situation ... 17
5.1 Production Process ... 17
5.1.1 Collect order ... 17
5.1.2 Cutting Process ... 17
5.1.3 Marking Sleeves ... 19
5.1.4 Insertion of fittings and sleeves, The End Connection ... 20
5.1.5 Crimping the hose ... 22
5.1.6 Insert PVC and Crimp PVC ... 23
5.1.7 Roll Up Process ... 24
5.1.8 Assemble Couplings and Nipples ... 25
5.1.9 The Testing Process ... 25
5.1.10 CIS-tag Process ... 26
5.1.11 Paper work ... 26
5.2 Factory and Production ... 27
5.2.1 The Factory ... 27
5.2.2 The Production ... 28
6 Situation Analysis ... 31
6.1 Product Range Analysis ... 31
6.1.1 The Purpose of Product Range Analysis ... 31
6.1.2 The Product Range ... 31
6.1.3 Product variation ... 32
6.2 Production Processes Analysis ... 33
6.2.1 Time consuming processes ... 34
6.2.2 Non-added value processes ... 44
6.2.3 Overall production analysis ... 50
6.3 Cost calculation analysis ... 53
6.4 Layout and Overview Analysis ... 54
6.4.1 Layout analysis ... 54
6.4.2 Material supply system ... 56
6.4.3 Production methods and Lean thinking ... 59
6.4.4 The location the production manager office and lack of leadership ... 60
7 Concept Generation and Choice ... 61
7.1 Production Processes ... 61
7.1.1 Testing Process ... 61
7.1.2 CIS-tag process ... 65
7.1.3 Protection Hose process ... 67
7.1.4 The Cutting Process of Twin hose ... 68
7.1.5 Roll Up Process ... 69
7.1.6 Cutting Single Hose ... 72
7.1.7 Marking the Hose ... 74
7.1.8 Fittings and Sleeves insertion ... 76
7.1.9 Marking the Sleeves ... 79
7.1.10 Handle long and heavy hoses ... 80
7.2 Layout and overview ... 82
7.2.1 Production Layout ... 82
7.2.2 New production method, 2+1 concept ... 85
7.2.3 Material Supply ... 86
8 Summary and Discussion ... 91
9 Further Work ... 93
10 References ... 94
11 Appendix ... 97
11.1 Appendix A ... 97
11.1.1 Sleeve data ... 97
11.1.2 Fitting data... 97
11.1.3 Pressure class ... 97
11.1.4 Length analysis ... 98
11.2 Appendix B... 101
11.2.1 Production orders with most detailed process times ... 101
11.2.2 Cutting process of Twin hose ... 103
11.3 Appendix C ... 106
11.4 Appendix D ... 115
11.4.1 Cost and process calculations for new processes ... 115
11.5 Appendix E ... 115
11.5.1 Layout concepts ... 117
11.5.2 Production methods concept ... 117
11.5.3 Stations in the new layout ... 118
11.5.4 Material supply ... 119
List of Figures
Figure 1 A CEJN High Pressure Hydraulic Hose with different End connections ... 4
Figure 2 CEJNs High Pressure Hose with CEJNS High Pressure Hydraulic Couplings ... 4
Figure 3 CEJNs CIS-tag applied on a hydraulic hose ... 5
Figure 4 Line side stocking feeding policy, Source: (Kilic, 2015) ... 9
Figure 5 Kitting feeding policy Source: (Kilic, 2015) ... 9
Figure 6 Layout types depending on production volume and production variety. Source: (Mukhopadhyay, 2011) ... 10
Figure 7 Hose Storage Construction ... 17
Figure 8 Stop Block and Hydraulic Hose ... 18
Figure 9 Stop Block ... 18
Figure 10 The cutting process of hydraulic hose ... 19
Figure 11 The Set Up process for marking machine ... 19
Figure 12 Sleeve marking machine ... 20
Figure 13 Hose Marking Process ... 21
Figure 14 Sleeve insertion machine ... 21
Figure 15 Fitting machine ... 22
Figure 16 Crimping machine ... 22
Figure 17 Un-coiling construction for protection hose ... 23
Figure 18 Crimped protection Hose ... 24
Figure 19 Rolling Up process ... 24
Figure 20 Testing process for Hose Assemblies with Couplings ... 25
Figure 21 CIS-tag process using a Heat Gun ... 26
Figure 22 A virtual 3D model of the factory ... 27
Figure 23 A virtual model of the production area ... 28
Figure 24 Location of stations and machines ... 29
Figure 25 Hose length Analysis ... 32
Figure 26 The process times for production order 8 ... 34
Figure 27 Process times for production order 9 ... 35
Figure 28 Process steps for the testing process ... 36
Figure 29 Process time for production order 10 ... 37
Figure 30 Process steps for the CIS-process ... 38
Figure 31 Process time for production order 9 ... 39
Figure 32 Process time for protection hose vs length of the hose assembly ... 39
Figure 33 PVC process for the production order 7 ... 40
Figure 34 Set up process for PVC roll ... 41
Figure 35 Process times for production order 1 ... 42
Figure 36 Cutting Process for Twin hoses ... 43
Figure 37 Sleeve insertion process ... 47
Figure 38 Process times for fitting insertion ... 48
Figure 39 Fitting machine ... 49
Figure 40 Crimping process for 30 meter hydraulic hose ... 50
Figure 41 Sleeve marking process ... 51
Figure 42 Changing the production information in the letter block ... 51
Figure 43 Marking machine ... 52
Figure 44 Current production layout ... 54
Figure 45 The locations of the material storages in the factory ... 57
Figure 46 Thread Couplings ... 62
Figure 47 Connection block to test multiple hose assemblies ... 62
Figure 48 Quick Clamping System ... 63
Figure 49 Heat Shrinking Tube Machine ... 65
Figure 50 CIS-tag size vs Shrink Tube size ... 66
Figure 51 A guidance device ... 69
Figure 52 Connecting Roll Up machine to cutting machine concept ... 70
Figure 53 Connecting Roll Up machine to cutting machine concept ... 71
Figure 54 Cutting Counter ... 72
Figure 55 Feeding machine ... 73
Figure 56 Hose marking machine ... 75
Figure 57 Adapter with a coupling and nipple solution ... 76
Figure 58 One Box for every adapter ... 77
Figure 59 New Marking machine ... 79
Figure 60 Letter block with a rolling mechanism ... 79
Figure 61 New production layout concept ... 82
Figure 62 Working area with the new production layout concept ... 84
Figure 63 Material Supply collection spots ... 86
Figure 64 New location of production managers office ... 88
Figure 65 New pick up location for produce hose assemblies ... 89
List of tables
Table 1 Ranking table for the most time consuming processes ... 33
Table 2 Added value %age table ... 44
Table 3 Material supply operations ... 58
Table 4 Total time and cost savings for the testing concepts ... 64
Table 5 The total time and cost savings for the protection hose concepts ... 67
Table 6 The total time and cost savings for the Twin Hose concepts ... 68
Table 7 Total time and cost savings for the Roll Up concepts ... 71
Table 8 Time and cost savings for cutting single hose concepts ... 74
Table 9 Tme and cost savings for the Hose marking concept ... 75
Table 10 Time and cost savings for fitting concepts ... 77
Table 11 Time and cost savings for the sleeve insertion concept ... 78
Table 12 Time and cost savings for the marking machine concept ... 80
Table 13 Time and cost savings for the crane concept ... 80
Table of descriptions
ABBREVIATION EXPLANATION
PVC Protection Hose
NNVA Necessary non-added value
NVA Non-added value
ID Inner diameter
OD Outside diameter
CIS CEJN Identification System
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1 Introduction
This section describes the background of the project, what objectives the project has and the scope of the project.
1.1 Background
With a globalized and interconnected world with rapid development in logistics and transport infrastructure, companies are more and more centralizing their business to achieve scale advantages in production and in administration. Companies can nowadays effectively reach out to customers and markets that they could not do before which enables companies to centralize their business and offer competitive prices. This have created a business environment with many competitors and with highly pressed prices that can compete with locally produced products.
CEJN AB, which is a manufacturer of quick connect couplings is afraid of this situation and is now seeing an opportunity through this project to stop the chances of potentially losing market shares by competitors centralizing their business and offering better prices.
In recent years, CEJN AB have built up a world leading position for producing quick connect couplings for ultra-high hydraulic pressure and together with the hose manufacturer Parker Polyflex in
Germany, they offer customers a full product package with couplings and hoses for ultra-high hydraulic pressure applications.
The leading global market position has been built up through domestic hose assembly production by CEJNs subsidiaries all around the world.
In the last two years, CEJNs competitors have copied the product range of quick couplings in the ultra-high hydraulic pressure area and together with a hose manufacturing company, they can now offer a similar product package as CEJN AB and Parker Polyflex. CEJN and Parker still has a slight technical advantage over the new competitors but the growing competition increases the need to look over the production process, productions cost, logistic and the product service.
The hose assembly process is today performed by CEJN AB’s subsidiaries all over the world and due to the low production volume at most of the subsidiaries, the assembly process is rather an
ineffective and costly process.
A threat is beginning to rise from the competitors, where their lack of subsidiaries in the different countries, they have the possibility to build a large production facility with high production volume with good logistic and e-business that can compete with CEJNs local-based subsidiaries. Due to the increasing competition and the potential threats, a new production concept needs to be developed where CEJN can remain as the market leader and offer the customers the best solutions.
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1.2 Objectives and Aim
The objectives for this project is to help CEJN AB to remain market leaders by developing a new production concept that will compete with the competitors and remain market shares.
The objectives and aims of the project:
Map the whole hose assembly process and perform a situation analysis at CEJN Germanys production facility in Troisdorf.
Analyze the current product range in the German production facility to assess product variation, set up time and lead times.
Identify the production cost in the hose assembly production at CEJN Germany in Troisdorf.
Identify areas of improvement in the assembly processes and develop solutions to reduce production cost and increase production capacity.
Identify and develop improvements in production layout to optimize the production flow, material flow and information flow.
Perform an analysis of the current production technology, tools and equipment and propose new solutions to increase production capacity and reduce production cost.
1.3 The Thesis Scope
The scope of the project is to:
Reduce the production cost with 20 % at CEJN Product Gmbh in Germany.
Increase production capacity for a potential centralization of the European production
Reduce lead times for the hose assemblies to be able to deliver the same day
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2 Context
This section contains information about the company where the master thesis is performed, the company’s production facility and the company’s products.
2.1 The Company
CEJN AB is one of the leading quick connect coupling manufacturers in the world with a local
presence providing innovative solutions and value to customers. CEJNs focus is on high quality quick coupling products with attention to performance, safety and environment secured through own development and production.
CEJN is a family owned business with its roots in Sweden, since its start in 1955. Today, the CEJN Group consists of 17 sales companies and 5 production facilities, and has 550 employees worldwide.
The head quarter is located in Sweden and in the town Skövde where most of production and product development is located.
CEJNs core products are quick connect couplings and nipples for all types of media, from compressed air to gas, breathing air, fluids and hydraulic oil. CEJN products can be found in diverse fields as agriculture, automotive, construction, offshore, medical, marine, transportation, wind power and rescue, just to mention a few industries.
CEJN has over 40 years of experience in quick connect coupling technology for high-pressure hydraulics (700-4000 bar) and offers a wide range of products with operating pressures up to 4000 bar. CEJN High-Pressure Hydraulic couplings are specially designed for applications in bolt tensioning, torque tools, rescue tools, test applications etc.
2.1 The Production facility In Germany
CEJN AB has 17 sales offices around the world and one of them is located in Troisdorf, Germany. In Troisdorf, CEJN-Product Gmbh have a production facility that are producing hose assemblies for High-Pressure hydraulic applications and a warehouse for CEJN AB products.
The production facility consist of four assembly workers that assemble around 17 000 hose assemblies in 2016. The factory also consist of warehouse where three people work.
2.2 The Hose Assembly
The product that are in focus in this project are CEJN AB´s Hose Assemblies for High-Pressure Hydraulics. The CEJNS Hose Assemblies can consist of different components depending on customer requirements.
However, the main components in a CEJN hose assembly are:
1. Ultra High-Pressure Hose
CEJNs Ultra High-Pressure hoses for hydraulics are spiralized steel reinforced polymer that has ultra-high working pressure with maintained flexibility. Its low volumetric expansion give fast response time in hydraulic systems while smooth inner bored provides a minimized pressure drop. CEJN AB can offer Ultra High-Pressure hoses in pressure ranges 700-4000 bar. CEJN AB offers both single hoses and Twin hoses.
4 2. End Connection
End connections are assembled on the ends of the Ultra High-Pressure Hose and depending on the customer, CEJN AB can offer a large amount of various end connection types to suit the customer’s different requirements. The end connection can be divided in two components, the fitting and the sleeve. A hose with different types of end connections are presented in Figure 1.
Figure 1 A CEJN High Pressure Hydraulic Hose with different End connections
3. Couplings
CEJN is manufacturer of quick couplings, and on the end connections of the hose assembly, these couplings can be mounted. Depending on what type of application, media and pressure, these couplings vary. CEJNs High Pressure Hydraulics couplings assembled on the CEJNS Hydraulic Hose is presented in Figure 2.
Figure 2 CEJNs High Pressure Hose with CEJNS High Pressure Hydraulic Couplings
5 4. Accessories
Depending on the customer, different accessories could be assembled onto the hose assembly to address the different customer needs. There are different accessories such as the protection hose, which will increase the product life by protecting the High Pressure-hose from abrasion and dirt. A CIS-tag is another accessory which CEJN AB is offering, which is applied on the hydraulic hose. This tag contains all the information about the hose assembly; when it has been produced, which components it contains etc. All this information is readable through CEJNS own mobile application. In the Figure 3 below, the CIS-tag is illustrated.
Figure 3 CEJNs CIS-tag applied on a hydraulic hose
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3 Theoretical Framework
This section contains relevant theory related to the research that links the thesis to existing knowledge.
3.1 Lean Production
3.1.1 Identifying Waste
To increase productivity and rationalize a production, identifying waste in individual value streams and find a way route to remove or reduce this waste are necessary according to (Dinesh Seth, 2017).
An increased productivity leads to leaner operations that will expose even further waste and quality problems in the system. The basic idea behind lean is waste elimination, cost reduction and
employee empowerment (Anvari et al., 2011).
There are three types of operations in an internal manufacturing according to (Monden, 1993). These can be categorized into:
1. non-value adding (NVA)
2. necessary but non-value adding (NNVA) 3. value-adding (VA)
Non-value adding operations are pure waste such as transportation, material handling, walking, counting, loading and removal of a part in a machine.
Necessary but non-value adding operations are wasteful operations but needed to perform the work assignments. These operations are for example unpacking deliveries or transferring tools from one hand to another. To eliminate these type of operations, big changes needs be made on a new layout or in new equipment.
Value-adding operations are operations that adds value to the product and gives value to the customers. These operations are for example sub-assembly of parts or forming raw material.
3.1.1.1 5QMS
Hirano (2009) further lays out the 5QMS production waste factor. The 5MQS identifies different type of waste, five of which begin with the letter M: Man, Material, Machine, Method and Management.
The Q and S stands for Quality and Saftey. People-related waste are for example walking waste, watching waste and searching waste.
In JIT-production (Hirano, 2009), the policy is that the workers stands while working and that walking and working is not the same thing. Walking usually takes about one second per step and to reduce this walking waste the question “Why does the worker take X number of steps?” needs to asked to be able to reduce the amount of steps.
Watching waste, is where the worker for example watches the machine do its work. To avoid this type of waste, JITs “Human automation” makes a point of clearly separating machine work from human work (Hirano, 2009).
Searching waste, is waste where the worker for example searches for tools, equipment or material.
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3.1.2 Batch size effects and Just-In-Time production
Just-in-time production mainly focuses on reducing set-up time, producing in small lots, and analyzing production process to identify non-value added activities or waste and eliminating them (Bayo-Moriones et al., 2008). The author further stated that, to effectively produce in smaller batches or in single-piece flow, the reduction of set ups is needed. By reducing the set up time in the production, great improvements can be achieved through higher efficiency and flexibility.
Poor quality, rework, and scrap are inherent to large batch manufacturing. As result, large quantities can be produced before the problem can be detected by downstream processes (Crandal 2002).
3.2 Material Supply
3.2.1 Manual Picking
The workplace design and the design of the materials exposure is the most important part of
assembly productivity, according to (Baudin,2002). Furthermore, the author states that the goal is to have the material available to the assembly worker at arm’s length. The problem in achieving this is obvious when the number of components and variants increases, and there is no longer room to expose the components.
3.2.2 Feeding policies
Caputo and Pelagagge (2011) presents in their paper that there are three main types of feeding policies; Line side stocking, kitting and kanban-based feeding. Moreover, (Limere et al., 2012 and Faccio 2014) is discussing and presenting a fourth feeding policy, hybrid-feeding policy, where more than one feeding policy is used to match the product mix and different products characteristic.
Hybrid feeding policies including the combinations of line side stocking, kitting and kanban-based feeding will play an important role and provide solutions in the future according to (Kilic, 2015).
Limere, 2015, discusses the importance of taking into account the operator walking distance when deciding to between kitting and line stocking. The potential to reduce walking distance increases the attractiveness of kitting even for large work stations with abundant space. Furthermore, the author studied how part and product mix characteristics affect the choice between kitting and line stocking.
The probability for kitting is higher for parts that are less voluminous, belonging to larger part families and supplied on pallets, allowing for batch picking.
Line side stocking policy, each material is stored in individual container near the assembly lines and distributed to the stations from a central warehouse. Line side stocking is the oldest of the feeding policies (Faccio, 2014). In Figure 4, the line side stocking feeding policy is illustrated.
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Figure 4 Line side stocking feeding policy, Source: (Kilic, 2015)
The feeding policy kitting, can be defined as the activity of supplying required parts to the assembly lines in determined quantities that are put together in specific containers (Corakci, 2008). In Figure 5, the kitting process is illustrated.
Figure 5 Kitting feeding policy Source: (Kilic, 2015)
3.3 Workers health
Falck, (2014) examined the relationship between assembly ergonomics, assembly complexity and quality failures by analyzing manual assembly tasks in car manufacturing. The results showed that the more complex assembly tasks there are the higher the action cost and both ergonomics and
complexity conditions affect failure rate to a high degree. The author than further stated that assembly ergonomics and assembly complexity factors interact and both should be proactively considered in order to keep assembly-related failures and action costs as low as possible.
According to (Falck et al., 2010), a clear relationship between assembly ergonomics conditions and assembly-related failures that affect the quality outcomes of the products produced have been seen.
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A high physical load level in manual assembly results in more quality defects compared to a low physical load level.
Zhu et al. (2008) discussed about the operator choice process and the complexity within it. The operator must choose the correct part from all possible variants according to the customer’s order.
These choices are often made under time pressure, e.g. collecting the correct material, tools etc. In high paced assembly lines, this often results in mistakes, quality errors and other assembly related failures.
Job rotation is considered as an appropriate strategy to reduce physical workload in human-based production systems to prevent musculoskeletal disorders, to increase job satisfaction and thus productivity (Boenzi et al., 2013a).
3.4 Layout
3.4.1 Choice of layout type
According to (Mukhopadhyay, 2011), A production layout is dependent on the production volume, process technology, handling and storage technology, the production variation and the management philosophies. Figure 6 shows the choice of layout depending on the product mix and production volume.
Figure 6 Layout types depending on production volume and production variety. Source: (Mukhopadhyay, 2011) According to (Mukhopadhyay, 2011), a facility layout should be able to address the following:
Changes in the design of an existing product or the product set to be produced
Changes in production sequences or in equipment
Changes in production quantities and schedules
Changes in organization structure and management philosophy
Changes in requirement for space, equipment and space
Furthermore, the author stated that to be able to incorporate the features mention above the layout needs to have modular facilities.
According to (Mukhopadhyay, 2011), the primary criteria for evaluating any layout will be to minimalize the material handling cost. The Material handling cost is typically proportional to the frequency of movement of material and the length over which material is moved.
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3.4.2 U-shaped assembly lines
U-shaped assembly lines have become more and more popular due to the operators ability to
perform more than one task located to different places of the assembly line (Liu, Ong & Huang 2003).
According to (Cheng, C. H., Miltenburg, J., & Motwani, J. (2000).) U-shaped assembly lines will improve the volume flexibility, a company can adjust the production rate by increasing or decreasing the operators. The author states, that this level of volume flexibility is harder to obtain with a straight line. The operator flexibility will increase due to walking distance is shorter in a U-shaped assembly unit than a straight one and the operator can oversee several work stations.
With a U-shaped assembly line, there are more possibilities for grouping tasks into workstations and the material handling will reduce due the elimination of material handling equipment such as conveyors.
According to Cheng, C. H., Miltenburg, J., & Motwani, J. (2000), the compact size of a U-shaped assembly line improves the visibility and communication, which will increase responsibility and teamwork.
3.5 Workers involvement
When modifying a work place or a production facility, the changes that will be made will have an effect on the workers within it according to (Airo, Rasila & Nenonen, 2012). When changing work environment, defensive behaviors may occur from the workers due to the uncertainty of their own future and the lack of involvement. To build up and maintain loyalty and commitment within the organization, the workers should be involved in the changing process and their voices should be heard. This will lead to a more open-minded workforce that will be more open for change due the feeling of involvement and ownership of the new changes to the workplace (Glover et al., 2014).
3.6 Automation in Assembly lines
According to (G Boothroyd et al, 1987), the largest single cost element in a production is product assembly. It is estimated that product assembly accounts for 50 % of the total manufacturing cost and employ more than 40 % of the total workforce.
An efficient way to achieve cost-effective solutions in a production is automation. Automation has also been extensive not only in the actual production process but also in supportive tasks such as material handling, transporation and storage (J Frohm, 2008).
According to (Parsuraman R, et al, 2000), Automation relieves humans from heavy, dangerous, complex, boring and time-consuming tasks. A common solution is to merge manual and automated operations into semi-automated manufacturing systems.
The interaction between a human and machine is becoming more and more important in industrial technology due to the increasing demand for high flexibility and productivity (Groover M.P., 2001).
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4 Methodology
4.1 Scope of work
The master thesis is founded on the literature review and the gathered information from the case study at CEJN Product Gmbh. The case study consists of a current state investigation, situation analysis, concept generation & choice.
The master thesis is done by one full time student over a period of 20 weeks. The scope of the work is limited to the hose assembly process.
4.2 Project procedure
This project has been approached as case study which is descriptive research looking at a set of individuals or unit in organization (Stake, Robert E, 2005). The data for the project have been collected by observations and the conclusions is relevant primary to the people or the unit involved in the process. Regular Case studies tend to look at exploring and describing problems but this project also focusses on the cause and effect.
The project plan was built on different phases, which have been a guideline to follow for reaching the projects set goals. A brief explanation of all steps and project phases follows:
1. Planning
The first project phase consisted of planning the project; decide the project time span, the limitations of the project and what is needed to reach the project goals. In the planning phase, questions such as why we are doing this project, who is doing it, how is it going to be executed and where and when the project is going to be performed where answered. All the aims and objectives of this project where clearly defined and discussed together with CEJN AB in this project phase.
2. Theoretical framework and Pilot study
This project phase consisted of collecting the necessary material and information to be able to reach the objective of the project. The theoretical framework was aimed at collecting the latest theories relevant to the project, which will than act as a base for the project. All the collected data and information from the theoretical framework should be applied in the project solutions and acts a guideline when generating solutions.
The pilot study consisted of collecting all the needed material from the different processes at CPG. All information and data about the products, the processes, the cost factors etc. where identified and collected to serve as base for potential solutions.
The pilot study also consisted of a visit to the hose supplier Parker Polyflex to get their input and experiences, also visits to equipment suppliers to get the latest technology plus a visit at CEJNs assembly plant for couplings to learn about their assembly strategies.
14 3. Situation Analysis
In this project phase, all the material gathered from the pilot study where analyzed and studied through different tools and methods. In the situation analysis, all the areas in which needs to be changed to reach the aims of the project should be identified.
4. Concept Generation
In the Concept Generation phase, potential solutions where generated to solve the problems identified in the situation analysis and to drive the project further to reach the set targets.
The concept outcome was built upon the theoretical base which was used when compiling the results from the case study.
5. Concept Choice
In this project phase, all the concepts generated from the conception generation phase where analyzed, compared and discussed with stakeholders through a set of criteria’s. After the concept comparison, the concepts that we agreed on and fulfilled the set criteria’s where chosen.
4.3 Project methods and tools
In this project, a broad number of project tools and methods where used in order to reach the projects aim and objectives. In this section, these methods and tools are described.
4.3.1 Data collection methods
The data collection methods for this project has been varying depending on which material that needed to be found. The data collections methods used in the project was observation, participation and including examining existing material, interviews, test, meetings and visits.
Data for the production analysis was gathered through observing, measuring and analyzing
production orders. All the operation times and processes were carefully measured with a stopwatch.
All the information and data that was not possible to retrieve from the production area at that time, was gathered from the assembly workers and the production manager through interviews.
The production volume at CEJN Product Gmbh was identified though CEJNs business system and all the information and data for the product range analysis was also collected from the business system and from CEJNS own website.
All the relevant data for the production costs analysis where collected from CPGs financial department.
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4.3.2 Tools and Methods
The following section describes the tools and methods used.
4.3.2.1 Process activity mapping
Process activity mapping is a method used to eliminate the production from waste according to (Jordi Olivella Nadal, 2008).
There are five stages to this general approach:
1. The study of the flow of processes 2. The identification of waste
3. A consideration of whether the process can be rearranged in a more efficient sequence 4. A consideration of a better flow pattern, involving different flow layout or transport routing 5. A consideration of whether everything that is being done at each stage is necessary and what
would happen if redundant tasks were removed.
4.3.2.2 5W1H
Another technique and method used in this project with purpose of identifying waste in the production and to increase the productivity, was 5W1H. 5W1H is method from the Toyota
Production System (Monden, 1993) where 6 questions are asked: Why does an activity occur, Who does it? On Which machine? Where? When? and How?
The basis and purpose of this method is to identify and try to eliminate operations that are un- necessary. The method is also used when trying to simplifying or combining operations and seek sequence changes that will reduce waste. This method increases the understanding of the processes and how processes could be improved.
4.3.2.3 Brainstorming
Brainstorming is a typical method for generating ideas (Baxter, 1995) and was used in this project to generate concepts on how to improve the production process, the production layout and to solve the identified problems from the situation analysis. All the brainstorming sessions started with a
clarification of the problem and then generating ideas on how to solve these problems.
4.3.2.4 Benchmarking
Benchmarking is broad research method (Camp, Robert C, 1989) where you compared different technologies in order to find the most superior solution. In this case, a benchmark at Parker Polyflex was done and with other industries where similar processes are used but not directly comparable.
4.3.2.5 Workshops
Another method used in this project to find the most optimal and risk free solutions was to organize workshops. Workshops was constructed to discuss potential solutions and problems with CEJNs own production personnel. The idea is to discuss and generate new solutions with experienced people and identify risks with the potential solutions and the implementation potential.
4.3.2.6 3D Simulation and modeling
3D Simulation was used in this project to improve the knowledge about the process and receive a visual understanding about the layout, the working process and the material flow. 3D Simulation was also used as tool for convincing the stakeholders to accept the new changes but also to improve their knowledge about the problems. By 3D simulating the working process and how the workers work,
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the workers received a more visual understanding about their working process and an understanding what is needed to improve it.
The whole production area, production processes and the whole factory was built up in a 3D simulation program, Jack 8,3. This method was used to improve the understanding on how every process connects to each other and receive more knowledge about the material supply system, layout and production flow etc. This method was used when generating new ideas for a new production layout.
The 3D simulation and the 3D modeling was performed in JACK 8.3.
4.3.2.7 CAD
Computer aided programs was used in this project to visualize concepts the on how to improve the production processes and also to show to the stakeholders for increasing understanding.
4.3.3 Limitations
The project is limited to CEJN Product Gmbh in Germany and focused on the hose assembly process.
The administration regarding the hose assembly process is being left out. Due to the time span and the width of the project, implementation phase is excluded in this project.
The project is only focused on Cejn Germanys production facility. Future centralized production for Italy, Spain and France will be possible because of improved production.
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5 Current Situation
This section describes more in detail the current production process and current production layout.
5.1 Production Process
A brief description of every production processes that a assembly worker performs during a hose assembly production.
5.1.1 Collect order
The first process of the hose assembly production process is to collect a production order. The assembly workers collects the production orders at the production manager’s office where it is being produced and printed out. The production order is in paper form and consist of all information needed produce the customer required hose assemblies. After that the production order is collected, the assembly worker walks back to the production area and starts preparing the production of the order.
5.1.2 Cutting Process
The High Pressure hydraulic hoses that are used in the hose assembly production are located in the hose storage construction. The hose storage construction can be seen in Figure 7.
Figure 7 Hose Storage Construction
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The first step in the cutting process is to adjust the position of a stopping block. The stopping blocks function is to hold down the hose when cutting and also decide the length of the hose by placing stopping block at the correct position. The length between the stopping block and the cutting machine is the wanted hose length from the customer. Figure 8 & 9 shows the design and function of the stop block.
After the position of the stop block is adjusted to desired length, the next process is to collect the correct hose type from the hose storage construction and pull it to the stop block as are seen in Figure 8. The assembly worker than attaches the hose into the stop block and uses an equipment to fastened the hose to the hose track.
When the hose is in the correct position, the next step is to apply tape and cut the hose. The function of the tape is to reduce the expansion of the hose after being cut and to protect the outer cover of the hose. These Ultra High Pressure Hoses contains 2-6 layer of spiralized steel wires, which will expand due to a removal of the outer cover when being cut. The Figure 10 below shows the location of the tape and how the worker is positioned when cutting the hose.
Figure 9 Stop Block Figure 8 Stop Block and Hydraulic Hose
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Figure 10 The cutting process of hydraulic hose
After the hose is cut to the desired length, the hose is placed on a transportation table and the process of cutting a new hose can start.
5.1.3 Marking Sleeves
After the hose is cut to the desired length, the next step in the production process is to mark the sleeves. The sleeve is being marked with the production date, month and year, and which pressure class. To mark the sleeve with the correct production information, the settings of the marking machine needs to changed to suit the hose assembly. The part of machine that contains the production information and the set up process is seen in Figure 11.
Figure 11 The Set Up process for marking machine
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After the settings are adjusted and the block is mounted back in to the machine, the marking
machine is ready to mark the sleeves. The assembly worker than places a sleeve under the block and pushes a button to make the block glide over the sleeve with high force and speed to mark the sleeve. The marking machine is presented in Figure 12.
After the sleeve is marked, the sleeve is removed by the assembly worker and placed in a box.
5.1.4 Insertion of fittings and sleeves, The End Connection
The next step in the production process is the insertion of fittings and sleeves onto the hose.
Depending on which type of sleeves and fittings that are being used in the hose assembly, there are different methods of inserting the sleeves and fittings.
Prior to inserting the sleeve on to the hose, the hose needs to be marked to know, how far the sleeve should be inserted in to the hose. The process of marking the hose is presented in Figure 13.
Figure 12 Sleeve marking machine
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Figure 13 Hose Marking Process
After the hose has been marked, the tape needs to be removed prior to the insertion of the sleeve.
The removal of tape is necessary due the tight tolerances between the sleeves inner diameter and the outer diameter of the hose. To insert most of the sleeves onto the hose, the assembly worker needs to use a machine due tight tolerances. Firstly, the sleeve is placed into the machine and than the hose is being pushed against the sleeve while it is being rotated by the machine as are seen in the Figure 14 below.
Figure 14 Sleeve insertion machine
After the sleeve is inserted on to hose, the next process is the insertion of fittings. CEJN AB offers a broad number of various fittings with different dimensions and designs. Due the large amount of different fittings, the process of inserting the fitting differ. If the fitting is difficult to insert into the hose, due to tight tolerances between the hose inner diameter and the fitting outer diameter, the fitting machine presented in Figure 15 needs to be used.
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Before the fitting is inserted into the hose, the hose is attached and fastened in the machine to ensure proper position. After the hose is fastened, the assembly worker aligned the fitting and the adapter attached to the machine. When the adapter of the machine is aligned with the fitting of the hose, the assembly worker than pushes the fitting in to the hose by the help of a lever. When the fitting is properly inserted, the hose is unfastened and a new insertion process can begin.
5.1.5 Crimping the hose
The next step in the production process of the hose assemblies is the process of crimping the hose.
Crimping the hose is a process were the sleeve, the fitting and hose are pressed together by a
crimping machine. This process is needed to ensure that the fittings and sleeve are properly sealed to the hose and that no leakage occur. The crimping machine is seen in Figure 16.
Figure 16 Crimping machine Figure 15 Fitting machine
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Firstly, the assembly worker places the hose inside the machine pressing the fitting against the cylinder. Through sensors, the crimping machine automatically starts crimping the hose inside the machine. Depending on what type of hose, fitting and sleeve, the hoses can be crimped 1-12 times.
When the hose is crimped the first time, the assembly worker has to rotate the hose to ensure that the hose is crimped at all places of the hose. If the hose is crimped 6 times at the same place, the result will be damaging and oval inner diameter will be the result. Both of the hoses ends needs to be crimped.
After the hose, sleeve and fitting is crimped, the assembly worker needs to check if the hose is crimped correctly. The assembly worker uses a gauge with a known diameter to check if the hoses inner diameter has the correct diameter. If the inner diameter of the hose is correct after crimping, then the hose is ready for the next production process. If the hose doesn’t have the desired inner diameter after being crimped, the machine settings needs to be changed or be crimped again with the same machine settings.
5.1.6 Insert PVC and Crimp PVC
Some of the hose assemblies that CPG are offering to customers consists of a protection hose. A protection hose is used to protect the hydraulic hose from dirt, oil and abrasion. The process of putting the protection hose on the hydraulic hose starts with pulling out the protection hose from an un-coiling construction seen in Figure 17.
Figure 17 Un-coiling construction for protection hose
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The assembly worker pulls out the protection hose to the required length and then cuts the protection hose. The protection hose is then placed into the special track to it hold fastened and straight. The hydraulic hose is then inserted by pushing it in to the protection hose. When the protection hose is inserted on to the hose, the PVC needs to be crimped to ensure that it occurs no leakage and that the PVC is fastened. The process of crimping the PVC is similar as the crimping of the sleeves and fittings. The results can be seen in Figure 18.
5.1.7 Roll Up Process
Hose assemblies longer than 2 meters are usually rolled up the ensure an easier material handling and to be prepared for the next coming processes. When working with short hose lengths, 2-4 meters, the hose assemblies are being rolled up manually by the assembly worker without any help from equipment. When working with longer hose assemblies, 4-30 meters, the assembly worker requires to use a roll up construction as are seen in figure 19.
Figure 19 Rolling Up process Figure 18 Crimped protection Hose
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5.1.8 Assemble Couplings and Nipples
Some of the hose assemblies produced in CPG contains couplings and nipples. The process of assembling the couplings and nipples starts with fastened the hose assembly in a vice. When the hose assembly is fastened, the assembly worker screws on the coupling or the nipple and then uses a torque wrench to tighten it by the correct torque. When the torque wrench makes a sound, the assembly worker knows that the coupling or nipple is screwed correctly.
5.1.9 The Testing Process
One of the last processes in the hose assembly production process is the testing the hose assemblies.
The testing of hose assemblies is performed to ensure that the components have been correctly assemble and that is no safety risk for the end customer. Depending on the hose assembly, the testing process will differ. The testing process can differ in testing pressure, testing media and how to install the hose assemblies into the testing machines.
The testing process starts with installing the hose assembly in to the machine. The process of installing the hose assembly in to the machine depends on if the hose assembly contains couplings and nipples or only end connections. If the hose assembly have nipples and couplings, the hose assemblies can be tested simultaneously by assembling them together with adapters. If the hose assemblies only have end connections they needs to be tested separate, one by one, due to inability to assembled them together. Figure 20 presents the testing process for Hose assemblies with couplings.
Figure 20 Testing process for Hose Assemblies with Couplings
When the hose assembly is installed in the testing machine, the assembly worker fills up the hose assemblies with test medium. After the process of filling up the hose assembly with test media, the testing process can begin. The testing machine starts to build up pressure inside the hose assembly
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to a certain test pressure and holds it at this pressure for a certain amount of time. During the testing time, the assembly worker inspect the hose to identify any leakages.
After the testing process is finished, the test medium needs to be removed from the hose assembly by using an Air Gun. After the testing medium is out of the hose assembly, the assembly worker dismantles the hose assembly from the machine.
5.1.10 CIS-tag Process
The next step in the production process of hose assemblies is the CIS-tag process. The CIS-tag process involves 4 process steps.
The first process step is to cut the shrink tube to a desired length. The next step is to apply the shrink tube on to the hydraulic hose. The CIS-tag is than placed and applied under the shrink tube and onto the hydraulic hose. After the shrink tube and the CIS-tag is applied, the assembly worker than uses Heat Gun, blowing hot air onto the shrink tube, making it shrink and cover the CIS-tag.
The process of blowing hot air on the shrink tube can be seen in the Figure below.
Figure 21 CIS-tag process using a Heat Gun
5.1.11 Paper work
The final process involves booking out the produced hose assemblies from the business system and print out checklists and Test certificates for the customers.
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5.2 Factory and Production
At CEJN Product Gmbh, the facility is divided into two sections, an office building and a factory building. The factory building consist of a production area and warehouse area. The production area is where the hose assembly process is being performed and the warehouse area is where the material handling processes occur.
5.2.1 The Factory
A virtual model of the factory was built up in Jack 8.3 to present the current factory layout. The 3D model can be seen in figure 22.
Figure 22 A virtual 3D model of the factory
In Figure 22, the layout of the factory and the sections within it are presented.
Description of every section in the factory:
1. Production Area
This area is the hose assembly production. Here is where all the hose assemblies are being produced and the assembly workers work.
2. Storage
Most of the products and components that CPG receives from CEJN AB is stored in these 4 racks.
3. Elevator storage
In the elevator storage, all the couplings and nipples are stored and also accessories for the hose assemblies.
28 4. Packaging area
This section of the factory is where the warehouse personnel are packing customer orders and prepare it for delivery. Mostly smaller boxes are being prepared here.
5. Delivery and packaging area
This section is where bigger boxes are being weighed and prepared for delivery. Here arrives most of the hose assemblies that have been produced from the production area.
6. Office
The only office from the office building that is presented in Figure 22 is the office related to the factory. In this office sits the warehouse manager and the production manager.
5.2.2 The Production
The production area is represented by a virtual 3D model and are presented in the Figure 23.
Figure 23 A virtual model of the production area
In figure 24, all the locations of the different stations and machines are highlighted.
