Supplier Selection when Considering Risks for Disturbances in the Inbound Flow to Scania
Supplier Selection When
found interesting material in literature used in courses at Lund Institute of Technology.
When making the empirical studies, interviews were the main method used. These were con-ducted both in groups and individually with key personnel at Scania. Interviews were not always formally recorded due to their informal structure.
Continuously through the process feedback was collected from Scania to revise the model.
What is Supply Chain Risk Management?
Supply chains of today that comprise hundreds or in some cases thousands of companies, extending over several tiers, present numerous risks. Broadly these risks can be classified into two categories:
risks arising from within the supply chain and risks external to it.
Risks within the supply chain arise from interac-tion between constituent organizainterac-tions across the supply chain. It is caused by sub-optimal interac-tion and co-operainterac-tion between the entities along the chain. Such risks may be the result of lack of
“ownership”, self-imposed “chaos”, just-in-time practices and inaccurate forecasts. External risks arise from interactions between the supply chain and its environment. Such interactions include disruptions caused by strikes, terrorism and natu-ral catastrophes.
Together, supply chain risks and risks external to it, impact the vulnerability of the supply chain.
Simultaneous occurrence of both risks and inter-actions between them intensifies the damage to the supply chain. With this in mind a reasonable definition of supply chain vulnerability would be:
“an exposure to serious disturbance, arising from risks within the supply chain as well as risks external to the supply chain” . /1/
Supply chain risk management aim at identifying potential risks and implementing appropriate ac-tions to diminish those risks. Thus it can be de-fined as:
”the identification and management of risks within the supply chain and risks external to it through a coordinated approach amongst supply chain members to reduce supply chain vulnerability as a whole”. /2/
Developing the Model
Four goals guided the construction of the model: creation of an instrument for risk man-agement in the procurement process, increased risk awareness in the purchasing process, crea-tion of a basis for supplier seleccrea-tion decision and simplicity for the user. Emphasis was put on increasing the purchasers risk awareness and simplicity.
The basis for the model consists of the three parts of the risk management process: risk analysis, risk evaluation and risk reduc-tion/control (figure 1).
Figure 1, Basic model. /3/
Scope definition
Boundaries of the study are confined upstream by the inbound flow to the suppliers produc-tion unit and downstream by the off-loading dock at the Scania production unit. This area include tiers upstream the supplier and the transport chain between the supplier and Scania.
Hazard identification
Hazard identification can be conducted in a number of ways. In this study a purely qualita-tive search for disturbance risks was made.
Through the use of key words risk parameters were derived. Identified parameters where then divided into three priority groups based on their influence on supply chain vulnerabil-ity.
Risk analysis
Risk evaluation
Risk reduction/control
Scope definition
Hazard identification
Risk estimation
Acceptable risk
Analysis of options
Monitering Implementation Decision making Risk analysis
Risk evaluation
Risk reduction/control
Scope definition
Hazard identification
Risk estimation
Acceptable risk
Analysis of options
Monitering Implementation Decision making
Supplier Selection when Considering Risks for Disturbances in the Inbound Flow to Scania
Priority group A consists of the following pa-rameters:
1. Strategic supplier; due to the suppliers unique knowledge and/or strong ties to Scania it is hard to replace
2. Strategic-/bottleneck product; products that if interrupted causes disruptions or disturbances to Scania
3. Logistics complexity; poor distribution networks and complex transport routes causes increased risks
This group constitutes the basis for risk estimation in the next section.
In group B a number of parameters was used for the risk evaluation (acceptable risk and analysis of options). These are:
1. Tool ownership; loss of production tools in the case of supplier running bankrupt 2. Supplier risk awareness
3. Supplier market strength; a strong sup-plier might prioritize other customers in a bottleneck situation
4. Insurance coverage; induces risk aware-ness and protection against bankruptcy 5. Production limitations; bottlenecks and changes in the production process might cause increased probability for disruption 6. Infrastructure; poor infrastructure
be-tween the supplier and Scania increases the logistics complexity
7. Catastrophic events; force majeure related occurrences like earthquakes and flood-ings
As stated above these parameters are included in the risk evaluation described in coming sections.
Parameters in group C where not considered use-ful in the model but still constitute a source for identifying risks in the supply chain. These can be found in the thesis.
Risk estimation
To conduct the initial risk estimation a preliminary hazard analysis (PHA) method was used. The aim with PHA is to eliminate those suppliers that don’t constitute a measurable risk to the supply chain. All other supplier options will undergo further analysis in the risk evaluation process (coming sections).
To estimate the risk a basic decision tree was used.
Through the use of the risk parameters in priority group A, strategic supplier, strategic-/bottleneck product and logistics complexity, a level of risk is derived. There are three levels of risk, high,
me-dium and low. Low risk means that the supplier can be chosen without any further analysis. High and medium risk suppliers must undergo the next step in the model.
Acceptable risk
Formation of the risk evaluation tool was based on a multi-attributive decision making (MADM) technique called analytical hierarchy process (AHP). MADM is basically a number of techniques that can be used to evaluate competing alternatives that are defined by multiple attributes. /4/
AHP is essentially the formalization of our intuitive understanding of a complex problem using a hierarchical structure. A hierarchy has at least three levels: focus or overall goal of the problem at the top, multiple criteria that define alternatives in the middle and competing alternatives at the bottom. Through pair wise comparison one can assign weights to the different attributes related to their
contribution to the overall goal. I this case the overall goal is “best supplier”.
The hierarchical structure consists of four levels beneath the overall goal (figure 2).
Firstly attributes are divided into operative risks and business criteria. Operative risks comprises of risks internal and external to the supply chain. Internal risks are parameters 1 to 5 of group B in the hazard identification and the external are parameters 6 and 7. Business criteria are divided into quality, cost, design and product design change flexibility. As-signing weights to attributes is done as described above.
Analysis of options
There are mainly two alternatives suitable for the comparison of suppliers. A more complex method is to continue the pair wise
comparison further down the hierarchy. That is to compare all attributes with each supplier.
As level 4 comprises 11 attributes this takes some time. The recommended way is to use a simple index method. Suppliers are given a rate from one (very bad) to five (very good) for each of the attributes. The total index
score is then computed by multiplying the compa-rable rating for each attribute by the importance weight assigned to the attribute. These are then summed and the sum constitute the index-value for that supplier.
When this has been done with all competing al-ternatives (suppliers) one receives a ranking list that reflects to what extent suppliers fulfils the overall goal “best supplier”.
Decision-making
Decision-making is a complex process and com-prises not only concrete parameters. One of the aims with this model is to deliver a basis for deci-sion making for purchasers at Scania.
There are numerous decisions to reduce risk of current interest. Some examples of such decisions are presented below:
– Redesigning the product – Choose other supplier – Risk reducing measures – In-house production
Together with the last steps, implementation and monitoring, this comprises the main part of risk management model. Hence the model can be defined as a tool used in an uncertain supplier selection situation resulting in a basis for decision-making.
The Supply Chain Risk Management Model
In the sections above the principles for devel-oping and using the model was described. On the next page a more pragmatic description is presented (figure 3). This picture represents the finished model for supply chain risk man-agement. A more thorough description of the model and its practical use is found in the thesis (in Swedish). Vertical dotted arrows in the models middle level constitutes the appro-priate working pattern when using the model.
The model as presented in figure 3, is ready for use in almost any supply chain. As it was originally constructed for the auto industry, use on other supply chains might create the need for modifications. But due to the flexible nature of the model this is not a major prob-lem.
Conclusions
Supply chain vulnerability is without a doubt an increasing problem for many companies.
This is partly a result of time- and resource optimized production, outsourcing and a glob-alized economy. Every day disturbances in the inbound flow occur at Scania, which in turn generates increased production costs. In the event of a disruption one also have to take into account goodwill losses.
Best supplier
Operative risk Business criteria
Internal External
Quality Cost Design ECO
-flexibilityt Infrastructure Catastrophic
events Tool ownership Supplier
risk awareness
Supplier
marketstrength Insurance Limitations in production
Supplier E1 Supplier E2 Supplier E3 Supplier En
Figure 2: Supplier selection hierarchy
Best supplier
Operative risk Business criteria
Internal External
Quality Cost Design ECO
-flexibilityt Infrastructure Catastrophic
events Tool ownership Supplier
risk awareness
Supplier
marketstrength Insurance Limitations in production
Supplier E1 Supplier E2 Supplier E3 Supplier En
Figure 2: Supplier selection hierarchy
Supplier Selection when Considering Risks for Disturbances in the Inbound Flow to Scania
The risk management model presented in this article has an important task to fulfill in the sup-plier selection process. It can add substantial value to the procurement process in any company.
As a whole the model has certain limitation in its applicability to Scania. This is mainly a result of the low risk awareness among the purchasers, which makes it somewhat complex to handle.
However very positive feedback was given to the PHA-part (preliminary hazard analysis) of the model. A PHA like the one presented in this arti-cle can easily be used to create an increased atten-tion to risk in the supplier selecatten-tion process. Fur-ther the model contributes a great deal to the aca-demic and industrial knowledge in supply chain risk management.
References
/1/ Supply Chain Vulnerability (2002). Cranfield University, School of Management. UK. (p. 2) /2/ Ibid
/3/ International Electrotechnical Commission (IEC) (1995): Risk analysis of technological systems.
Genéve.
/4/ Hwang & Yoon. (1995): Multiple Attribute Decision Making – An Introduction. Sage University Paper. USA (p. 2)
Decision making Analysis of options
Acceptable risk Risk estimation Hazard identification
Scope definition
•Inbound flow to supplier
•Supplier production and processing
•Transport and distribution to Scania
•Receival at Scania PRU
•Qualitative analysis
•Risk derivation through key-words
•Three priority groups (A,B,C)
•Groups A and B used in coming steps
•Ranking list part of basis for decision making
•Index method used to rate suppliers
•Supplier given rate (1 to 5) for each attribute
•Each rate multiplied with attribute weight
•Result in index-score and supplier ranking-list
•AHP-method assign attribute weights
•Five level hierarchical structure
•Operative risks and business criteria guides
•Base for evaluation of competing suppliers
•PHA-method eliminate low risk suppliers
•Decision tree with group A parameters
•Supplier receives rating high, medium, low risk
•Medium and high risk undergo next step
Figure 3: The Supply Chain Risk Management model Risk analysis
Risk evaluation
Risk reduction/control
Basis for supplier decision-making Supplier selection
in uncertainty
Implementation /monitoring Decision making Analysis of options
Acceptable risk Risk estimation Hazard identification
Scope definition
•Inbound flow to supplier
•Supplier production and processing
•Transport and distribution to Scania
•Receival at Scania PRU
•Qualitative analysis
•Risk derivation through key-words
•Three priority groups (A,B,C)
•Groups A and B used in coming steps
•Ranking list part of basis for decision making
•Index method used to rate suppliers
•Supplier given rate (1 to 5) for each attribute
•Each rate multiplied with attribute weight
•Result in index-score and supplier ranking-list
•AHP-method assign attribute weights
•Five level hierarchical structure
•Operative risks and business criteria guides
•Base for evaluation of competing suppliers
•PHA-method eliminate low risk suppliers
•Decision tree with group A parameters
•Supplier receives rating high, medium, low risk
•Medium and high risk undergo next step
Figure 3: The Supply Chain Risk Management model Risk analysis
Risk evaluation
Risk reduction/control
Basis for supplier decision-making Supplier selection
in uncertainty
Implementation /monitoring