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International Journal of Production Research

Vol. 48, No. 10, 15 May 2010, 2975–2993

Managing lean manufacturing in material handling operations

James C. Green, Jim Lee* and Theodore A. Kozman

Engineering Management Program, Department of Mechanical Engineering, University of Louisiana at Lafayette, P.O. Box 44170, Room 244 CLR Hall, Lafayette, LA 70504-2250, USA

(Received 17 July 2007; final version received 8 January 2009)

The problem addressed by this research is to implement lean manufacturing ina material handling system of a petroleum drill bit manufacturing company. Leanmanufacturing has been mandated by higher level management as a tool to be

used in waste reduction. Operational group must define the objectives of leanmanufacturing and deploy the tools to specific work cells. A methodology thatprovides operational group with a tool to assist in defining the objectives of leanmanufacturing is developed. A case study is used to demonstrate the leanimplementation in material handling operations.

Keywords: material handling; lean manufacturing; case study; value streammapping; diamond drill bit components

1. Introduction

The proper flow of materials through manufacturing processes allows industries to

generate and maintain a competitive edge. This edge is the ability to meet customerdemand for on time delivery, generating good customer satisfaction. The proper selection

of material handling systems and manufacturing concepts such as lean manufacturing

(Hobbs 2004) help to facilitate increases in productivity. Lean manufacturing is based on

the elimination of waste, both value added and non-value added, from the processes that

are used to produce goods and services (Feld 2001). These lean tools also contribute to

creating a safer and more ergonomic work environment.

Material handling is defined, simply, as moving material. This is the popular

perception that many hold, but in fact material handling includes much more than simply

moving material. For a significant number of manufacturers, material handling can

account for more than one-half of the total cost of manufacturing. The flow, movement,and storage of materials in the manufacturing processes of firms often require a great deal

of resources, both employees and equipment. Material handling is also regarded as being

a non-value added function that is still necessary for the successful completion of the

manufacturing process and can have a marked affect on the ability of a firm to meet

managerial goals (Myers and Stephens 2000). The cost generated by material handling

systems can be reduced if steps can be taken to improve these systems. Productivity and

the incidence rate of injuries, specifically lost time injuries, can also be improved by

positive changes to material handling systems.

*Corresponding author. Email: [email protected]

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The problem addressed by this research is to implement lean manufacturing in

a material handling system of a petroleum drill bit manufacturing company. Lean

manufacturing has been mandated by higher level management as a tool that will be used

to assist in waste reduction. Operational group must define the objectives of lean

manufacturing and deploy the tools to specific work cells. A best practice of lean

manufacturing implementations is to approach the event slowly by implementing in

a single pilot cell and then continue to spread to other areas of the organisation (Wilson

2008). Our case study will be limited to the implementation of the developed methodology

and lean manufacturing principles in a single cell to support the use of this best practice.

A review of lean manufacturing literature related to materials handling is presented in

Section 2 of this paper. Based on the methods and tools available, a methodology is

developed in Section 3 which can be used to implement lean concepts in materials handling

systems. The step by step procedure described in the methodology is then followed by

a case study in Section 4. The performance evaluation of the lean implementation is

summarised in Section 5. Our concluding remarks are presented in Section 6.

2. Lean manufacturing in materials handling

Lean manufacturing is a tool that many companies focus on for continuous improvement

of processes. Long term strategies as well as short term goals of these firms involve

implementation of lean manufacturing to eliminate waste and boost performance.

However, many of these companies only undertake the initial strategic move of defining

lean manufacturing as a philosophy and never provide functional roadmaps to daily

operational teams for the implementation of lean manufacturing. Biddle (2006) indicates

that the time and resources to sustain lean manufacturing are often not provided by top

management to operational teams.

One of the key areas where a sustained lean manufacturing implementation can have

great affects on the performance of a company is material handling. Flinchbaugh (2005)

points out that lean manufacturing applied to material handling should encompass all

available lean manufacturing tools, consist of a complete view of the technique, and not be

an extension or single facet of a lean manufacturing implementation. Management should

look at the problem completely and consider all key concepts and techniques, regardless of

the focus of the lean manufacturing implementation (Cutcher-Gershenfeld 2002).

Five key steps for implementing lean manufacturing to material handling systems are

defined by Harris and Harris (2006). These steps include:

(1) Develop a plan for every part.

(2) Build the purchased parts market.

(3) Design delivery routes.

(4) Implement pull signals.

(5) Continuously improve the system.

While these steps are valid for many material handling systems, they do not provide

a method for determining specific goals for a lean manufacturing implementation into the

material-handling system.

Schieber (1999) approaches the problem of determining a more effective way of

handling stock packaging materials in a food industry firm. The method used to conductthe study was focused on employee involvement and reducing the occurrence of back

2976 J.C. Green et al.

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injuries by manually handling the stock material. Cochran et al. (2000) states that system

design methods must be tied into the objectives of the system, and piece-wise

implementations are ineffective if the overall objectives are not understood. This point

relates directly back to the need of developing a method to define the specific objectives of

a lean manufacturing implementation.

Review of lean literature indicates that no specific methodology for determining

objectives of lean manufacturing in regards to material handling is available. The

significance of developing such a methodology can help operational teams to determine

what exactly they wish to accomplish when implementing any given cell:

. What does the solution need to provide?

. What waste is to be reduced?

. How will the process be affected?

. What metrics should be used to evaluate the results?

3. Methodology

The methodology used to determine objectives of lean manufacturing in a material

handling system of a machine cell involves several steps. These steps begin with

management input to determine the goals of the business unit and the operational group.

A lean manufacturing assessment must be conducted to determine the potential locations

of waste reduction. Development of a lean manufacturing strategy will help determine how

lean manufacturing assists in the overall implementation strategy and how the potential

solutions can be prioritised for selection and implementation.

The definition of objectives for lean manufacturing are determined as a result of the

prioritisation and comparisons of possible solutions and the overall strategy. Theimplementation of lean manufacturing tools and solutions development assists in

determining how the implementation of the tools and solutions will fit into the process

and how several concepts can be followed as guidelines to help ensure the success of the

implementation. Finally, the solution is implemented and monitored through selected

metrics to gauge continuous improvement and reinforce objectives and goals of both the

work cell and business unit.

3.1 Management input

Management input includes the objectives of the organisation as defined by highermanagement as well as the business objectives of the operational groups and teams. The

primary goal of the operational group is to define the specific tasks, processes, and

resources that will be used in the production unit to meet the business goals defined by

higher management (Stevenson 2002). The key focus, regardless of what tool is

implemented, is meeting the goals of the operational group so that the higher level

goals of the organisation can be reached and customer needs met.

The input of management is very important. This input lays the basis for deployment

of the methodology and affects the development of any possible solutions. Many facets of

the organisation beyond high level production management affect the overall performance

and objectives of the operational groups. Even though these operational groups or plantsreport through the higher level production management group, they also take some

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direction and input from other functional groups such as human resources, finance and

accounting, technology and research and health, safety and environmental groups.

3.2 Lean assessment

Once the business unit goals of the operational group have been defined, a lean

manufacturing assessment must be undertaken to determine where areas of opportunity

exist for improvement. With material handling being the focus of this research, the lean

manufacturing assessment should focus on the way that materials flow through the

processes of the organisation and how this material flow affects what is expected of the

operational group. The assessment must be done while keeping in mind that the focus of

any lean manufacturing implementation is the removal of waste from the system.

The lean manufacturing assessment can be carried out in a variety of ways. The two

most effective ways of assessing are (1) value stream mapping, looking at the current

process flow and what is desired in the future flow, and (2) analyse the facility layout,

including logistics used to move products in relationship to where the products originateand their destination. A typical value stream map would look at all steps of the process as

the product moves from one operation to the next, including all the time that the product

would spend in queue, in transport, being worked on, and waiting for set-ups and

administrative work to be completed. When addressing material handling, value stream

mapping and analysis of facility layout must take into account every movement of the

product regardless of the distance or time that it takes to perform the movement.

3.3 Development of lean strategy

The development of a lean manufacturing implementation strategy that is in line withoperational group objectives is very important. The development of this strategy will show

how lean manufacturing tools are tied into business unit objectives and thus lead to the

definition of operational group objectives.

The first step in the development of the strategy is to decide the location of the initial

implementation within the value stream. The area that this decision will point to will be

based on the results of the value stream, the area that has exhibited the most waste, and

management needs, specifically what areas can or cannot be addressed based on capital

requirements or operational importance.

Once the area, or cell, of the initial implementation is identified every occurrence of

material handling in the cell must be reviewed and compared against the objectives of theoperational group. The business objectives of the operational group can consist of such

things as specific productivity or through-put numbers, engineering and safety goals, raw

materials and consumables projections, direct hours, and overtime hours worked versus

those planned. Management must prioritise them and compare them against any possible

solution that is presented to eliminate waste in material handling from the chosen cell.

3.4 Definition of objectives of lean manufacturing

Once the solutions and their affects on the goals have been prioritised, the decision

to move forward with an implementation can be made. The selected solution will havea set of steps or processes that must be carried out for successful implementation.


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The process steps of the solution, their completion, and the series of metrics selected to

measure them are the objectives of lean manufacturing in regards to material handling

systems of the selected cell. These objectives of lean manufacturing are based on the

operational group and what they must accomplish to meet the greater goals.

3.5 Implementation of lean tools and solution development

The selected solution should be developed using all available lean manufacturing

tools. Both the equipment used as well as the process involved in material handling

should be examined to determine the best steps when applying these tools to the area

that has been selected to eliminate waste. It is most beneficial when a holistic approach

is used.

Feld (2001) stresses that there are five primary elements of lean manufacturing and that

these elements cover the full range of issues that surface during an implementation. These

elements and the tools associated with them give the basis of the tools and measurement

techniques that can lead to a successful solution and implementation. Some examples of

tools that can be applied to the solution or used to implement that solution are cell layout,

operational rules, total productive maintenance and 5S. Each of these tools approaches the

lean manufacturing solution and implementation from either the process standpoint, such

as cell layout and operational rules, or from the equipment layout, such as total productive

maintenance and 5S. When combined with effective metrics for material handling, such as

travel distance, space utilisation or productivity, optimal benefits can be gained in the

elimination of waste.

3.6 Solution implementation and monitoring

The implementation of the specific solution must be performed by the individuals who are

responsible for operations in the pilot cell. If these employees do not have responsibility

for making the improvement, then they will feel that they cannot be held accountable for

its success and therefore will have no vested interest in making it work. The team chartered

with the implementation must keep this in mind and to maximise return when assigning

members of the pilot cell who will assist with the implementation.

To monitor the implementation, metrics should be selected carefully. Each metric

selected should not only correspond to the defined goals and objectives but also to the lean

manufacturing tools and solution component used to meet these goals and objectives. The

importance of monitoring the implementation and recording metrics plays into one of themost important factors of lean manufacturing, continuous improvement. All metrics

should be recorded and charted to show how the solution is progressing. These charted

solutions need to be made available to all employees, especially to those of the work cell

where the implementation is taking place. The best way to show these metrics to all

employees is to post them in the location of the cell.

By posting the metrics in the work cell, several things can be accomplished. The first is

that the employees in the cell can have constant visibility of how the implementation and

solution are affecting their performance and reaching the objectives of the cell. The second

is that confidence is built in the philosophy of lean manufacturing. The third is that all

members of the organisation can see how and when additional efforts may be needed tocontinuously improve the effort to reduce waste in the system.


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4. Case study

The case study was performed at a manufacturing facility of the industry leader for

petroleum field diamond drill bits for oilfield services industry. The facility is

approximately 15,000 square feet and accommodates roughly 100 direct employees,

support staff, and management. The facility is divided into a series of heat process andmachine tool cells that allows for the production of a variety of product lines.

The industry focus and use of material handling systems is a result of the need to move

parts and components of parts through a variety of manufacturing processes. Material

handling systems in the industry must be able to blend into this mix of machine tools and

heat process cells, giving operators the ability to bring products to market.

In this case study, top management has prescribed that lean manufacturing needs to be

phased in to complement total quality management in defining the culture of the company.

The purpose of the case study was to develop a solution for a material handling problem

by following the steps outlined in the methodology section for lean implementation in

regards to a selected work cell.

4.1 Management input

To begin the study, information was collected from the operational group on specific

business goals of the facility. Discussion was also held on how important material handling

is to the facility and the need to make improvements wherever opportunities exist.

Management did, however, discuss the need for any immediate changes to have minimal

negative affects to production due to the current business environment.

To align with best practices of implementing lean in a pilot cell and with a project that

could result in an ‘easy-win’, it was determined that the material handling needs of a single

cell would be initially addressed. It was also determined that the pilot cell would be chosen

by the following factors: the results of the lean manufacturing assessment, business needs,

and management discretion.

Table 1 displays the information collected from the management on business unit

goals. This table also displays the specific goals of the operational group. These goals will

be instrumental in defining the objectives of lean manufacturing in regard to material

handling during the deployment of the methodology.

Table 1. Business unit and operational group goals.

Focus Business unit goalOperational group goal

(research focus)

Operations Improve overall productivity by 10% Improve productivity by 10%Maintain on-time-delivery rate Improve cycle time by 5% to ensure OTD

rate maintainedBegin lean manufacturing

implementationImplement one lean manufacturing project

Growth Increase overall capacity by 20% Increase capacity by 25%Reduce recordable incident rate Reduce recordable incident rate by 25%

Safety Identify and mitigate hand safety risks Reduce hand injury rate by 30%Address material handling risks Mitigate material handling risks


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4.2 Lean assessment

Figure 1 shows the general layout of the crown machine cell and a lean assessment was

arranged for the cell. The lean manufacturing assessment included the first stage of value

stream mapping, creation of a current state map, as well as assessing the opportunities that

exist in the current state map. The current state map outlines the steps of the crown

machining process before any opportunities are addressed and aids in identifying waste in

the process.

The current state map is displayed in Figure 2. It is important to keep in mind that this

current state map is based on material handling in the cell and not the actual operations of

the cell, machining and assembly of drill bit components. For this reason a modified value

stream map was used in place of a conventional value stream map.

Value stream maps can be represented in several ways depending upon the scope of the

project. Tapping et al. (2002) indicate that the value stream map can define activities and

measure times from receiving to finishing of parts; it can define activities that take place

from time of order until cash is received; it can define activities and measure time from

conceiving product to its launch; or it can be geared toward the specific scope of theproject. The basis of the value stream map developed is determined based on the ability to

coordinate lean manufacturing tools to the specific details and scope of the lean

manufacturing projects undertaken.

When the value stream map data is tabulated, it helps to show where changes to the

material handling operations may have an impact on waste reduction. Based on the

information collected in Table 2, process stream A has the greatest opportunity for

improvement. The potential areas for improvement or waste locations in Process Stream A

can be summarised as below:

(1) The reduction of time to transport and place shank components in the inventory

area.

(2) The reduction of handling shanks from inventory area to the crown machine cell.

(3) The reduction of staging time in the crown machine cell.

(4) The reduction of handling time to move the component into the machine to attach

to the crown.

Figure 1. Cell layout.


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With these potential waste locations identified, the next step is to develop a lean

manufacturing strategy based on business unit objectives to remove waste.

4.3 Development of lean strategy

With the decision made to begin the implementation in the crown machine cell and with

the areas of opportunity identified, the methodology leads to developing the lean

manufacturing strategy. The lean manufacturing strategy was developed by reviewing

business unit goals and comparing the potential opportunities to these goals. From the list

of goals for the research location listed in Table 1, the following truncated goals were

selected for the comparison:

(1) Improvements to productivity.(2) Improvements to cycle times.

Figure 2. Material handling value stream map – CM cell (CM, crown machine).


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(3) Reduction in recordable incident rate.

(4) Reduction in hand injuries.

The goals of increasing capacity and mitigating a material handling risk were not used

for the comparison. The main reason for this is that because by the nature of this research

the result of any solution will be the implementation of a lean manufacturing project that

will identify and mitigate material handling risks. A second reason is that addition of

resources, such as machines and personnel, is not within the scope of this research.

Therefore, any gains made from a solution will be potential productivity increases,

through-put increases and safety improvements. The research will not focus on gains that

result from adding resources that will have a direct affect on increasing capacity.

The waste locations used in the comparison were those defined through the

value stream analysis. These areas of potential opportunity are included in Table 3,which displays the comparison. Several generalised solutions for the areas of opportunity

Table 3. Solution comparison.

Business goals

Total impactfactorSolution

Wastelocation Affected A B C D

1. Move location of shank inventory 1 Y Y N N N 12 Y Y Y Y Y 43 Y Y Y Y N 34 N N N N N 0

82. Change the process of staging shanks

in the crown machine cell1 Y Y Y Y Y 42 Y Y Y Y Y 43 Y Y Y Y Y 44 N N N N N 0

123. Change the way shanks are delivered

and handled in the crown machine cell

1 Y Y Y Y Y 4

2 Y Y Y Y Y 43 Y Y Y Y Y 44 Y Y N Y Y 3

154. Incorporate new lifting and handling

devices to attach shank to the crown1 N N N N N 02 N N N N N 03 N N N N N 04 Y N Y Y Y 3

35. Change the way that shanks are staged

in the crown machine cell1 Y Y Y Y Y 42 Y Y Y Y Y 43 Y Y Y Y Y 4

4 Y Y Y Y Y 416

Waste locations: (1) the reduction of time to transport and place shank components in the inventoryarea. (2) The reduction of handling shanks from the inventory area to the crown machine cell.(3) Reduction of staging time in the crown machine cell. (4) Reduction of handling time to move thecomponent into the machine to attach to the crown. Business goals: (A) improve productivity;(B) improve cycle time; (C) reduce recordable incident rate; (D) reduce hand injuries.


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were generated. Each solution was compared for its possible affect on the areas of

opportunity and on the goals of the research location.

The results reported in Table 3 display the areas of opportunity that can be addressed

that will have the greatest impact on meeting managerial goals. These results show the best

potential solution for meeting the requirements of management and also give the general

idea behind any future development of specific solutions.In examining the potential solution ideas, it is evident that only three unique solutions

have been presented. Solutions 2, 3, and 5 can be combined into the more general potential

solution of ‘Improving shank handling within the crown machine cell’. Table 3 also shows

that these three solutions individually have a greater total impact factor than either of the

other unique potential solutions.

4.4 Definition of objectives of lean manufacturing

Several general solutions were developed that have the potential of addressing theidentified waste locations and meet business goals. Based on the potential solutions listed

in Table 3 and the description of the potential solutions, the following prioritisation was

made:

(1) Improving shank handling and staging within the crown machine cell.

(2) Move location of shank inventory.

(3) Incorporate new lifting and handling devices to attach the shank to the crown.

The prioritisation list provides the priority that lean manufacturing project solutions

should be implemented in the cell. The prioritisation list along with the information

gathered from the comparison, waste locations, and company goals can be used to clearly

define what the objectives of lean manufacturing are in application to material handling

in the crown machine cell.

The top three objectives of lean manufacturing in regards to material handling for the

crown machine cell are:

(1) Develop and implement a solution for improved shank handling and staging in the

crown machine cell.

(2) Reduce the potential for recordable injuries, specifically hand injuries, through

implementing the developed solution for improved storage of shank components in

the crown machine cell by reducing manual handling of the shanks and improving

the ease in which shanks can be identified and retrieved.(3) Increase the productivity and through-put of cell operators through implementing

a staging device and procedure that will create a Kanban system for operators so

parts can be pulled through the cell.

These priorities call for the development of an improved staging system and

procedure to use in eliminating waste from the material handling system of the crown

machine cell.

Several lean manufacturing tools were used to assist in the development of a storage

device that could place the components for ease of use and conform to reducing the space

demands that the previous method of staging shanks in the cell required. The primary lean

manufacturing tools that were used to develop the staging device and the specifications forplacement and use in the crown machine were centred on the five primary elements of lean


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manufacturing defined by Feld (2001). Table 4 displays the five elements and the toolsselected for use from each element. They can be used as a baseline for development of

a handling and staging system that can mitigate material handling issues in the crown

machine cell.

4.5 Implementation of lean tools and solution development

The first project selected to implement was to develop a device that would restructure the

way that shanks were stocked when needed at point of use. The project called for the

development and fabrication of a device that could store shanks vertically, holding

a maximum number of parts safely. A vertical storage arrangement would allow foroptimised space utilisation. The device would also allow the operator to retrieve parts

Table 4. Lean manufacturing tools used to develop solution.

Primary element Tool Usage

Manufacturingflow

Process mapping Provide a comparison between the current state and thefuture state once the solution is implemented. Thistool will assist in gathering metrics for plottingprocess improvement.

Metrics Space utilisation Optimise available space and show improvement bycomparing current space with space needed and usedfor new system.

Travel distance Offer a metric to use for determining if the exposure tohandling parts has reduced for the goals of minimis-ing recordable hand injuries and improvingproductivity.

Process control Visual control Compare visual signals to determine if the new systemutilises visual cues that signal the need for re-supplyof parts that improve upon current methods.

5S housekeeping Implement 5S to reduce clutter in the cell and improvecell cleanliness reducing hazards that can lead toinjury.

Organisation Training Cell operators must be trained to properly utilise thenew system with the specifications outlined by thelean implementation

Communication plan Clear communications must exist between management,cell operators and inventory personnel. This willallow for the clear flow of information for thepurpose of reporting results, issues and needs.

Roles and responsibilities All personnel involved must know exactly what theirduties and functions are and how they should be

carried out.Logistics Kanban pull system A pull system can be utilised for the purpose of movinginventory through the cell instead of having partspushed in before they are prepared for processing

Operational rules Clear rules on the operations of the cell must be put inplace. This will ensure that operators, regardless of shift, know exactly what it is they are expected to doand conversely inventory personnel and managementknow exactly how they must support.


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based on size while keeping to the lean manufacturing concept of point of use, having

everything needed within 30 seconds or 10 steps. The solution also needed to

accommodate safety requirements as well as reinventing the method used for handling

and staging shank components in the crown machine cell. To complement the

implementation of the new staging device, a parts flow plan was created to ensure

smooth flow of materials from inventory and receiving to the staging location.

Figure 3 displays a conceptual drawing of the device. The device was designed to

support the storage of 46 shanks. Each level of storage was designed for various sized

shanks. The top level was designed to support shank sizes 1½ to 4½ inches (38 mm to

115 mm), the middle levels were designed for shank sizes 4½ to 7f inches (115 mm

to 200 mm) (the most common sizes), and the bottom level was designed for sizes 7f

to 9 inches (200 mm to 228 mm). Placing the shanks in this manner ensures that the

operator will not have to manipulate the larger parts from high positions. This creates

a more ergonomic location where only small parts, 30 lb (13.5 kg) or less, are handled from

the higher storage positions and the larger heavier shanks are stored lower allowingfor crane rigging or lifting using the legs.

Figure 3. Proposed staging device.


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The base was designed at 30 inches (762 mm) square with the top level 52 inches

(1320 mm) above the base and each level approximately 10 inches (254 mm) below the

preceding. Storage arms were approximately 11 inches (279 mm) long spaced 36 degrees

apart and at a 30 degree angle from the base. Each level was designed for 360 degree

rotation. Rotation of each level gives the operator the ability to handle shanks that are

staged at any location on the device from one location in as near a proximity to the

machining controls as possible considering safety and space constraints.

The main thought in the development of the device was the use of the lean

manufacturing tools selected from Table 4. The device was designed vertically to maximise

space utilisation and enable it to be placed as closely as possible to the operator’s control

unit on the NC lathe used in the cell. Each row was configured to hold a specific number of

parts, with the entire device holding enough parts to supply the cell for approximately 3 to

4 days. This would allow for restocking, on average, twice a week, unless customer

demand of specific completed bits forced parts lower in the order queue to be elevated.

This visual cue system that provides specific locations for parts to be stored and pulled as

needed creates a Kanban pull system.Tiered rows and storing parts by size also provides a visual signal that the operator

can use to determine when the restock needs to occur or if certain sizes that will be

needed have been stocked when required. The implementation of the project provided

the opportunity for the cell to also undergo a rearrangement that could be performed

based on lean manufacturing’s 5S theory. Altering the shank staging method to prevent

the parts from being stored on flat surfaces and on the floor removed a potentially

hazardous situation, which coincides with a portion of this theory. The opportunity to

clean and sort through other cell tools and work spaces fell naturally in line with the

implementation supporting the 5S concept and lean manufacturing project

implementation.A plan was put in place to train operators once the device was implemented. All

operators, inventory personnel, and management must be fully aware of best practices

when using the device and when manipulating to load or unload the device. To reinforce

the implementation and training, all employees involved must have clear communications

to keep materials flow moving as required. All employees must have clear knowledge of

what their respective roles and responsibilities are based on operational rules of the cell.

To support the creation, a materials flow plan was put in place during the

implementation. The purpose of the materials flow plan was to minimise the amount of

movement out of the cell that operators had to make to retrieve shanks stored in inventory

or not yet moved to inventory from shipping and receiving. Inventory personnel would beresponsible for placing shanks on the device in the cell, placing any excess parts in the

inventory area to use at the next restocking. It would then be the cell operators’

responsibility to inform inventory personnel of any rapid reduction in stock levels so an

accelerated restock could occur. Cell operators also had the responsibility of informing

management of such events so adjustments could be made to supply levels from vendors or

scheduling to maintain process output.

4.6 Solution implementation and monitoring

All necessary engineering and production drafting was performed for the device andsubmitted for quote proposal. Once proposals were returned the best overall solution,


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impact of the implementation of the solution. Table 5 displays the comparison of the

future state map performed after the implementation and the current state map created

before the implementation. As seen from the table, several improvements were made.

The first objective was to develop and implement a solution for improved shank

handling and staging in the crown machine cell. The shank staging device was developed to

facilitate meeting this objective. The device was designed specifically to accommodate the

geometry of the shank allowing for ease of loading as well as ease of shank selection andretrieval without increasing the time needed to perform these tasks.

Figure 5. Future state value stream map – CM cell (CM, crown machine).


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The second objective was to reduce the potential for recordable injuries by reducing

manual handling of shanks through improved methods to identify and retrieve the

parts from staging. A key metric that can be used to determine exposure time to

handling parts is the amount of time that the parts spend in transit, either during

transfer between work locations or during processing. It is clear from Table 5 that the

implementation of the solution had a marked affect on handling times. The handling

time from inventory to assembly was approximately 1020 minutes per week as

compared to 330 minutes per week.

The third objective of increasing productivity and through-put of the cell can be

measured in a similar way to that of reducing exposure to potential incident. As can be

seen in Table 5, the operations after the implementation of the device saved approximately

865 minutes per week, or 14.4 hours. If conservatively averaged at 14 hours per week

across the entire year of continuous operation, 50 weeks of production time, this adds up

to a time saving of 700 hours.

This is a substantial waste reduction and can be shifted either to improved productivity

or labour cost savings. If this saving is used to affect productivity, the facility cantransform 700 hours into additional throughput. An example is if it takes 50 hours to

produce a completed part, then an additional 14 parts per year can be produced. If the

savings are taken as a direct cost reduction, then if labour rates were charged, for example,

at $30 per hour, a saving of $21,000 could occur. These examples give an idea of how using

the methodology to develop a solution that defines management’s objectives and offers

a way to meet those objectives can positively affect the reduction of waste in the process of

material handling.

6. Conclusions

The manufacturing environment has had many tools available for the act of process

improvement. Lean manufacturing has proved to be one of the most successful tools that

manufacturing facilities can employ. However, this tool is often mandated by higher level

management as a way to reduce waste from manufacturing systems without a specific road

map to carry this out on a case by case basis. Providing this road map is the responsibility

of operational units.

A methodology was developed using several lean manufacturing concepts and the

material handling issues identified through assessing the cell selected for the implementa-

tion. Once the methodology was developed, it was applied to a case study at a leadingmanufacturing facility of the drill bit manufacturer. Specific objectives of lean

manufacturing were defined through careful use of the methodology and potential

solution concepts identified.

A specific solution was developed from the process of implementing the project

using many lean manufacturing tools. Key metrics were determined and monitored.

It was clear that the solution provided a method by which to eliminate a great deal of

waste from the material handling system. Due to this, the solution was carried to other

facilities with cells that performed the same or similar processes. By providing

a methodology for management to determine and meet goals, operational groups

can move toward providing road maps for the implementation of lean manufacturingprojects.


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