DEPLOYMENT THE MES (MANUFACTURING EXECUTION SYSTEM) AIMING TO IMPROVE
COMPETITIVE PRIORITIES OF MANUFACTURING
José Manoel Souza das
Neves
Centro Paula Souza – MSc. Program,
Brazil
E-mail: jmneves.fatec@gmail.com
Fernando Augusto Silva
Marins
São Paulo State
University, Brazil
E-mail:
fmarins@feg.unesp.br
Getulio Kazue Akabane getulio@akabane.adm.br
Centro Paula Souza – MSc.
Program, Brazil
E-mail: Getulio@akabane.adm.br
Roberto Kanaane
Centro Paula Souza – Msc. Program, Brazil
E-mail: kanaanhe@gmail.com
Submission: 23/05/2014
Revision: 25/05/2014
Accept: 14/11/2014
ABSTRACT
This work investigates the contributions of the MES – Manufacturing Execution System – for
improving the competitive priorities of manufacturing. We present a theoretical
framework on the information technologies (IT) and its business importance, the
contributions of the organizational factors for the implementation of the MES,
as well as the main concepts and the possible applications of this tool. The
built theoretical framework was decisive to subsidize the research performance
in the studied company. It was verified that the MES significantly contributed
to the manufacturing related to improvement of cost, quality, flexibility,
conformity and reliability. It was concluded that the MES enriched the
information quality generated from the plant floor, i.e., information that
makes it fast, standardized, reliable and precise. When integrated to the
Enterprise Resource Planning (ERP) of the company, the MES filled out a gap,
offering information other to other functional areas of the organization. The
interviews, conducted in businesses departments in the company, showed the
importance of the products tracking, and the MES implementation was decisive to
improve that issue, concluding that the dimension is considered as a
competitive priority of the manufacturing.
Keywords: Competitive manufacturing; MES - Manufacturing
Execution System; Organizational factors.
1.
INTRODUCTION
Global competition has caused changes characterized by manufacturing products with shorter and uncertain
life cycles demand, so enterprises have adopted innovative technologies for attending the
customers that are requiring fast supply, low cost, and greater customization.
The ability to quickly and effectively respond so as to meet the needs of
customers has become a competitiveness feature for many companies (DOWLATSHAHI
AND CAO, 2006).
In the search of differentiation and increased
production processes efficiency, the
industrial sector made major
investments in the automation of the plant floor in recent years, especially regarding the acquisition of hardware and software to support and to implement sensors, actuators and PLCs (Programmable Logic Controllers), updating the machinery and the supervisory systems SCADA (Supervisory Control and Data Acquisition).
With the new generation of information technologies,
specifically the enterprise
systems - ERP - Enterprise Resource
Planning, this mismatch information between the areas of the company
management could
be solved and
several problems can be avoided.
In this context, maybe the greatest aspect is related to the lack of a crucial link between the information
technology systems
adopted by the enterprise, like an ERP, whose lack or deficiency is evident between the automated
processes with
the other areas, ranging from production
management (Programming
and Production Control, Logistics, Supply), the purchasing area, as well the
financial and the human resources areas.
A solution to solve
this lack of communication between the productive area and the ERP is to adopt
the MES - Manufacturing Execution System that provides the necessary links to
improve these relevant relationships, and improving the competiveness of the manufacturing
process.
Unfortunately there
is few published works about the contributions of the MES system use, and this
paper is focused on this literature gap. On this way, this research was
developed with the intention of contributing to the knowledge expansion about
the implementing process of MES, and how it
improves the competitive dimensions of manufacturing. The research also aimed
to analyze what organizational factors can support the MES implementation, and
for that, it is presented a case study in an aluminum rolling company.
So, in short, this paper has aimed answering the following questions: What is the contribution of the implementation of the MES information
technology to
improve the competitive
priorities of manufacturing?
The paper is organized as follows:
a short background about Information Technology Systems and, in particularly
ERP and MES are presented, and in the sequence are described the research
method and the case study in an aluminum rolling company; finally are commented
the results and are suggested future works related to the theme.
2. BACKGROUND
Several studies discussed the implementation of the ERP in
several kinds of companies, focusing on its advantages, difficulties to its
absorption by
the professionals, critical success factors, impacts into the organization and its collaborators, the
relationship of the IT with the business
strategy, the increase of the competitive potential of the companies, and also the possibilities for adopting it in small and medium enterprises (AL-MASHARI AND AL-MUDIMIGH, 2003; BENDOLY AND SCHOENHERR, 2005; GUPTA 2000; NICOLAOU, 2004).
Some related applications on Information Technology (IT) Systems
literature have gained importance in the business area. So, technologies such
as CNC, CIM, MRP and MRPII, and CAD/CAM systems are the main examples, and they
are leading the companies, where they were deployed, to a qualitative leap and
competitive advantages in the global market. Particularly, in the manufacturing
area, the efficient and effective work, as well as the use of information,
became essential for an economic vitality and growth of the enterprise (MOLINA
AND SANTAELLA, 2006).
Several providers offer MES systems in the market, which are suitable according to the company needs. They are used in enterprises that have already had ERP systems as well as significant automated
processes on
the plant floor that will be integrated into the MES
system.
The MES
system ensures a more efficient management because it allows decision making based on relevant, current and reliable
information, allowing you to check what is happening in the manufacturing company. The MES also consolidates the planning and the mapping to the implementation of all production
stages, processing applications connected to the control of the
production systems, optimizing the production processes, democratizing and integrating information, and in this way
the MES provides a global view of production area and in a real time.
Figure 1 shows the desirable schematic view which comprises
the integration, the MES, the various organizational
levels, from plant floor to business management.
|
Figure 1: The integration of MES among plant
floor ITs and Enterprise Management Systems Source: SNOIEJ, 2006. |
According to HAYES AND WHEELRIGHT, (1984), manufacturing
companies have established their business strategies based on a hierarchical
structure. As an example, the operational strategy arises from the need to meet the functional
strategies that,
in the case of the
manufacturing area, generate competitive priorities to cope with the market
needs (SANTOS, 2000).
Each of the company's strategic areas was embedded with the IT solutions to
improve its efficiency and reach its goals. The main feature of these information
technologies is to support the fulfillment of the functional areas objectives. So, technologies such
as CAD, CAM, CAE, EDI have supported
the competitive
priorities of manufacturing, the ERP systems have provided the business management strategy.
|
Figure 2 - Integration of business management strategies with
the priorities of manufacturing from the IT systems and MES Source: Adapted from HAYES E WHEELRIGHT , (1984) |
Figure 2 shows the structure of the
company's strategies and the acting of the various IT solutions. It should be
observed that the IT resources used in functional areas, as well as in the
manufacturing area, do not generate available information to the top
management. Some occurs with IT solutions for management business that do not
reach to manufacturing. The MES system fills this gap, involving all functional
areas, and integrating the plant floor to the top of management level of the
company.
MESA (Manufacturing
Execution Systems Association), an international
association of companies
which provide integrated MES system, has been defined as a system that generates information and facilitates
the optimization of production
activities since the costumer order to finished
product.
KALL (1999) and CHOI ET AL (2002) define the MES, as a functional layer that integrates ERP systems and controls the plant floor in order to manage the
manufacturing production planning in a feasible manner. The MES fills
the gap between the ERP system and the automated
systems on
the plant floor.
According to BLACKSTONE JR. AND COX III (2004), the MES is a system of
information and communication for the
production environment of a company. The MES has the purpose to monitor and
to improve all aspects which influence the production
process, in
order to achieve high flexibility of production, as well as low production
costs. It
has also important features, which
allows production
records, production
reports, product tracking and details of the planning and
scheduling process.
For HWANG (2006), the MES is a process
information system that collects data, processes and analyzes materials, semi-finished and
finished products, equipment, time and cost, at the production site in a real time, i.e. it monitors the work while it is occurring. Concluding, the MES system operates as a hub for distribution of data on the plant
floor for all the other enterprise systems.
The MES
system include an information center composed of 11 elements or functions (see Figure 3), which are joined to other databases. These include the main functions of the MES (HWANG, 2006; KLETTI, 2007; SNOEIJ, 2006; YU et AL., 2009). The central idea is to measure in order to control so that the
performance indexes are used to compare the results of
the production lines within the same plant, company or with other known results.
|
Figure 3: Schematic of relationship between the various functions
of MES Source: SNOIJ (2006) |
The functions shown in Figure 3 are
integrated with Sales and Devices (MSS), Supply Chain Management (SCM), Enterprise
Management System (ERP), Engineering (PPE), and controls, which can generate the mechanisms
for production management through a fully computerized information, in a quick, safe and reliable way for the company (VINHAIS, 1998; HWANG, 2006).
The integration of the management
system with the operating
systems is crucial for the
companies whose
primary business is the manufacturing, since the key information such as financial
activities and accounting, inventory management and
asset management, are taken from the plant floor date.
3. METHOD
In this research, the goals were to investigate the implementation
of the MES
system in
the production process of an aluminum rolling company and to assess the resulting
improvement of the competitive priorities of manufacturing, having as supporters the organizational factors.
This research is guided by qualitative research making
use of interviews, through semi-structured questionnaires submitted to the main
professionals working in the deployment of MES system.
The method of case study concerns the study of a problem seen through multiple perspectives and in its original context. The research
was conducted by the method of a single case study, and the object of study consisted of a multinational
company, market leader in aluminum products.
The case study enables the development of new theory and the increased
understanding of real and contemporary events (SOUZA, 2005). The single case
study conducted in this research allows a better depth research and is commonly
used in qualitative research (MIGUEL, 2007). As recommended MIGUEL (2010)
research had a greater depth investigation.
The main way of collecting data was through semi-structured
interviews, additionally, the research method included visits to the factory
and plant floor observation. Internal documents
were consulted and selected to elaborate the questions for the interviews.
4. CASE STUDY
The studied company is a multinational, market-oriented and global leader in rolled aluminum with
respect to revenue, production volume and market share. The company has its headquartered in Atlanta - USA, and through its subsidiaries
and affiliates located in Asia, Europe, North America and South America in the areas of
mining of bauxite, alumina refining, power generation, production of primary
aluminum, in rolled aluminum and aluminum recycling, as well as it
has invested in research and technology.
It is a leading global supplier of aluminum rolled
products, the largest single buyer of aluminum and the world leader in aluminum
recycling. It has a
presence in four continents, 11 countries, with 34 operating units, and approximately 12,900 employees worldwide. The company is
the largest on laminates in the world and one of the biggest producers of
primary aluminum in Asia.
The productive
capacity of its plants is divided into the following main products: plates,
sheets, discs, sheets, billets, and finishing chemicals, beverage cans,
household utensils, civil construction, and in the automotive, transportation
and packaging segments.
The interviews ware
conducted with seven professionals from
the studied company, with a great experience and involved in the implementation of MES.
5. PROBLEMS OF THE STUDIED COMPANY AND MES
IMPLEMENTATION
The implementation of MES in the
studied company began in the early 2005 in the remitting area, but effectively
began operating in 2006. The MES was implanted, at the same time, in three
production lines for plates and recycling products in order to provide a unique
solution for the plant.
Considering the cold mill, the MES
project started in 2007, and its operation at the plant began in October 2008.
The MES replaced the existing system that was based on an Oracle system; its
implementation is still running and it is being made in a web environment.
There was an interest, in the area
of remelting, in the installation of the MES, because the sector is very much
automated and works with very large machine cycles, with at least 2 to 4 hours
each. Particularly the hot-rolling mill requires that several variables that
have to be set in order to have more stability in the final product.
It was verified that the problems
like lack of an adequate interface with the automation resources, the need of
performing nonconformity tests and the defect analysis, among other problems
were creating many difficulties and complexity for the operator. With the MES, the operator can insert
information data in the system without too much difficulty and without spending
a long time. In fact, all areas started to have
facilities for real time analysis, as for example, informing whether the
forecasted production time was used or whether some product nonconformity was
observed in the period.
The remitting area
is responsible by the process, its reliability and the people training. There
was already an automation structure focused on the process, but machine
interruptions had occurred and the information, like the stop machine
indicators, of these facts were not accurate. In the metallurgical process
cycles, there is the need of giving to the metal a rest during some time,
depending on the its size, kind of alloys, or even depending of its position on
the production list. The cold rolling mill needs a lot of information such as
chemical composition limits of thickness and width, as well as a lot of
information for each batch to be produced. Often, the equipment requires around
20 to 30 different parameters to machine setup in order to make a specific
product, and it is very difficult to machine operators perform a manual data
entry.
The remitting area produces in
batches, not in a continuous process, and a production order comes from the
customers needs. The ERP chooses which line will be used for manufacturing the
product and what product characteristics, while the MES contributes with the
information where is located the product (which furnace stage) and information in
which will be the next product to manufacture. The MES does not choose the
product position in the manufacturing order, but it monitors the progress of
the manufacturing order chosen. Monitoring the operators’ decisions, it checks
if the batch has satisfied the efficiency standards, and if this does not occur
it reprograms the production in order to increase the efficiency over time.
In the hot-rolling area, the
existing manufacturing modules of the ERP were without appropriate adjustments,
and so they did not meet the information needs and the appropriated integration
level with automation. Therefore, for it to be able to provide the same MES functionality,
and offer the same level of integration with the automation, several
adaptations would be necessary.
The
implementation of the MES enabled increased accuracy of the input data on the
ERP. One example was the production of monthly closings, which was made very
slowly and, therefore, the production data and the observations on the process
in real time made by the operators that could avoid production errors are
sometimes lost.
6. RESULTS
This section reports the results of the performed qualitative research
based on theoretical aspects and the case study. In this section, it is presented
the improvements observed in the studied company areas with respect to their
competitive priorities of manufacturing, as well as are identified the
organizational factors that can adequately support a MES implementation.
In the theoretical framework
available in the literature, seven competitive priorities of manufacturing were
identified (Costs, Quality, Delivery, Flexibility, Reliability, Product
Conformity, and Manufacturing & Strategic Business Integration). These
priorities, and the actions that are implemented by the company areas, are
tacitly established between the employees and the managers in the studied
company, i.e., produce the set out quantities (and achieve the goals) have
precedence in relation to these priorities.
Interviews with those managers
responsible for the manufacturing areas shown that the concern for cost
reduction and conformity attendance were clear, it also showed that had a large
integration in the manufacturing through the use of IT resources. In fact, the
whole managers training process and their involvement in the design and the
implementation of MES, it was made by the manufacturing area, by the IT
department, and by the MES developer (external).
There was a significant decrease in
gas consumption in the remelting area, not only by the performance of the MES,
but also by other lean manufacturing tools applied. With the double-checking of
the data entry of raw materials made by the operators and verified by the MES
system, there was a reduction of the non-conformity of the manufactured
products. This reduction increased the reliability of the area, and through a
data log of product manufacturing, enabled the tracking of the whole process in
a retroactive period of up to two years. With the reduction of failures in the
setup of the equipment, the quality of the product area had a significant
improvement. Table 1 shows these improvements in the remitting area.
Table 1:Improvement of competitive
priorities in
the remelting area – NEVES (2011)
|
Priority |
Remelting |
Observations |
|
Costs |
a) Reduced
consumption of natural gas (Approximately 5%). Natural gas is the second largest cost to the company. b) Rework reduction |
The reduction was also due to the implementation of other quality tools with the MES that contributed to the reduction of gas. |
|
Quality |
a) Reduction of failures in the setup. |
Only contribution of MES in order to implement double checking. |
|
Delivery |
There was no change. |
|
|
Flexibility |
Increased the flexibility of changing a production line to another. |
Only contribution of MES |
|
Reliability |
a) Registration data are available online, with the
possibility of tracking the entire process. |
Only contribution of MES |
|
Product Conformity |
Reduction of non-conforming signs. |
The reduction was also due to the implementation of other quality tools with the MES. |
|
Manufacturing
integration with strategic business |
Existing in the whole process. It is essential for business. |
|
The hot-rolling mill area had, as its goals, the reduction of the
production costs and improving the productivity with the implementation of MES,
as well as it could obtain a better lineup of the equipment with a consequent
reduction of gas consumption. There was also a significant reduction of
rejection in the products leaving the mill, and with the reducing the setup
time from 10 to 15 seconds per product (plate) was increased the area
productivity and its flexibility. The best ability to track and control the
production, in addition to the online availability of performance indicators (charts,
productivity, and use level) quickly led to a greater reliability in the area.
Table 2 shows the improvements with the implementation of the MES in the
hot-rolling mill of the studied company.
Besides that, in the hot-rolling
mill area, it was performed a further study on the implementation of the MES,
which offers more accurate quantitative information about the competitive
priorities of manufacturing. In an interview with the hot-rolling mill manager,
it was observed that there was a reduction in gas consumption in the
transformation process of the plates coming from the remelting area.
After the implementation of the
MES, it was reduced the use of gas from 24.4 m³ per ton of coil production to
23.7 m³ in the first year, and to 22.6 m³ in the second year. These numbers
show a total reduction of 252,070 m³ of gas use in the first year of
implementation of MES, and of 690,120 m³ in the second year. This reduction
generated savings values of US$68,500 in the
first year and of US$188,000 in the second year.
Table 2: Improvement of competitive priorities in hot rolling
area – NEVES (2011)
|
Priority |
Hot-rolling mill |
Observations |
|
Costs |
a) Better
furnaces scheduling, gas
consumption reduction. (1.5 min/pointer/plate). |
Improvements achieved only with the implementation of MES |
|
Quality |
a) Reduction of rejection in the reverse rolling mill. 1.7% to 0% rejection. |
|
|
Delivery |
There was no change. |
|
|
Flexibility |
Reduced setup time from 10 to 15 second per card laminated. |
|
|
Reliability |
Traceability and control of production, besides the online availability of the performance indicators (charts, productivity, use level) more quickly. |
|
|
Product Conformity |
Reduction of coils nonconforming. |
|
|
Manufacturing
integration with strategic business |
Existing in the whole process. |
Since the MES implementation, the hot-rolling mill began to receive data
on the products to be laminated, performing automatically the equipment setup
and significantly reducing the possibility of errors, in fact there were no
further rejections due to setup. Besides the improvement of competitive
priorities of manufacturing, it was unanimously reported by the three areas
that a great gain was the possibility of tracking the entire process, from the
its beginning (receive the product orders) including the handling of raw
material (remelting area), the finished products manufacturing (hot-rolling
mill and cold mill areas), and the final delivery to the customers.
7. FINAL CONSIDERATIONS
The few studies, available in
the scientific literature, did not characterize the importance of the MES
systems for the manufacturing area, and they showed that, in general, the
implemented MES systems have not relationship with the enterprise management systems.
During this research, it was evident the fact that ERP is not a system designed
to help in the manufacturing process improvements, mainly the automated and
computerized processes of the plant floor.
The
case study also allowed verifying that the implementation of the MES in the
studied company improved the competitive priorities of the productive areas, as
well as allowed identifying the organizational factors, which can support this
implementation.
A
relevant contribution of this research was an increasing
the perception of the MES as a system of integration of manufacturing with the
system of business management. The vision of the consulted areas of the studied
company showed the importance of the MES system related to the reliability of
the information about production processes and the information dissemination
across the functional areas of the ERP.
The MES was identified to be a complement to ERP systems and focused on the manufacturing areas,
allowing have traceability on their processes. In fact, this research showed
that traceability can be a competitive advantage for the company because, with
it anyone can immediately identify the entire route of a given product, from
raw materials coming from suppliers to the final product sent to the client.
Additionally, this ability to track the product position by the Web allows the final
client knows where is his order.
By the case study, it was found
that several organizational factors were important to support the
implementation of MES, such as: organizational
culture, organizational
learning, teamwork and training. Also,
it was observed that in all implementing process, the support of senior
management was very significant to secure funding the acquisition system
(including the interfaces, the hardware and the people training) that allowed
obtaining the returns on the investment due to the performance improvements.
Therefore, the IT resources of the company, including
the MES, should be integrated with the company's business organization to
ensure efficiency and the achievement of strategic objectives.
In the case study, for
the successful implementation of the MES and to reduce the impacts on the
people who were directly connected to the system, it was fundamental the
formation of teams comprised by leaders and area operators who were responsible
for the IT resources and the MES developer. These teams were multiplying in the
areas where the MES was implemented creating a value network to obtain positive
results with the system implementation. The observations and results obtained,
using MES, were converted into procedures and new knowledge for the company’s
collaborators. Also these experiences meant that the company has created a own
process of organizational learning in the implementation and in the use of MES.
Other contributions to
the business generated by this research are linked to the importance of the MES
for the manufacturing area and its importance in integrating with the business
and the organization.
The
case study had shown the improvement of productivity with the MES and the
reliability of data and information available. The possibility of having a
digital database allowed the traceability of the products. With the support of
WEB technology, the company can compare the projected manufacturing time with
the real-time obtained, and with these information can improve the decision
making process on manufacturing and the equipment utilization.
Usually,
the MES consolidates the planning and maps all production stages, it allows
improving the production processes, and the MES disseminates reliable and
important information, integrating the factory as a whole and in real time.
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