Discuss the concept of the internal customer who are purchasings internal customers

Who is the customer?

Customers can be either external or internal. In terms of needing to provide quality goods and services, it doesn’t matter much whether they are external or internal but external customers generally have a greater freedom of choice in their supplier.

Internal customers also need quality to carry out their functions effectively and one definition of the customer is ‘the next person or process to use my output’ - this can obviously be internal or external depending on where your operation is located in the supply chain. As an example, the output of the wages department is accurate wages and their customers are all internal, i.e. the staff.

Tip - Think of your wages as calculated by the wages department. Is near enough good enough in your wages? Is ± 10% OK? Is ± 1% OK? Do you expect a quality output from the wages department to their internal customers? If we expect quality from our internal suppliers then why shouldn’t our internal customers expect it?

Using this concept of the customer means that a supplier can also be a customer, e.g. the performance of the production area depends on accurate outputs from the purchasing department in terms of specifications, volume and order clarity.

My first car was a 1966 Ford Anglia 105E which cost AUD$400. It ran perfectly for 5 years with the only expenses being ‘consumables’ as such as tyres, brakes and new exhaust.

A truly quality car for a young driver.

Tip - The fact that somebody is supplying you with goods or services does not mean that you can treat them badly or provide them with poor information and services.

Customers/suppliers

A key issue for quality management is how we organise companies (see Section 2.7). The ‘departmental’ organisation model does not reflect the real ‘process’ orientation of actual companies and does not recognise that the ‘tribes’ of the company can become more important than the company itself, i.e. the people see themselves as part of the production department rather than as part of the company. The process model of a company accepts this and recognises the customers can be internal as well as external.

The old model of a company saw a set of suppliers sending raw materials to the company, the company doing ‘work’ (adding value) and then sending the product to the customer. The new model sees external suppliers sending raw materials to the company and then a series of supplier/customer relationships inside the company before the company sends the product to the final customer. These models are shown below and it is obvious that there will be many customer/ supplier relationships in any company. Suppliers do not have to actually pass physical products to the customer to be considered a supplier, i.e. if the accounts department is considered then the product could be considered to be high-quality accurate reports.

This is a radical change and the concept of internal customer/supplier relationships is quite strange to many companies.

Tip - I was pleasantly surprised when I asked an injection moulding operator who his customer was and his immediate unprompted reply was ‘The assembly area’. Things are changing and the operators understand it too (maybe better in some cases).

The ultimate responsibility for a quality product lies with each and every one of the employees. A perfect system may not produce quality products because it is ignored or poorly applied but a less than perfect system may produce good-quality products because of the enthusiasm of the workforce.

The people make all the difference.

Production Problems

When the machinist, assembly operator, or any other internal customer has a design or documentation problem and wishes to request a change, a simple method of communication with the cognizant engineer is required. This could be a simple form to fill out. This form may be called a request for change, engineering action request, etc. An email containing the required information may be effective. Have the requests sent to CM. The change form (ECO) should generally not be used for reasons that shall be discussed later.

Rule: Have CM train the production management and they, in turn, can train their people as to the method for identifying problems/requesting changes.

Reason: This will allow better action on operations issues.

Coordinate the training with manufacturing and engineering folks so that distinctions can be made between design and process documentation/changes. The information required on the request for change should be limited. Keep it simple. Prepare a form and form instruction that indicate those blocks that must be completed by the requester. A hard copy of the form should be available for those who do not have a personal computer.

Identifying Internal Customers

If the above seems complicated, consider how difficult it can be to identify internal customers. How is one supposed to know who the internal customers are?

Fortunately, the situation is not as complicated as it might seem. Identifying customers can be as simple as referring to the definition developed earlier, and asking the question: Who receives or is influenced by the product or service my group provides? Simply identifying those who are affected by a product or service will reveal who can be pleased or displeased by it. Those people are your customers.

5.2 DESIGN FOR SIX SIGMA STEPS

As shown in Figure 5.3, these are the DFSS steps:

Define the project goals and customer (internal and external) requirements.

Measure and determine customer needs and specifications (LSL and USL); benchmark competitors and similar industries.

Analyze the process or product options to meet customer needs.

Design (detailed) the process or product to meet customer needs.

Verify the design performance and ability to meet customer needs.

In general, DFSS is a function of measurement and design variables (independent factors).

DFSS = f (measure variables, design variables)

The following DFSS steps should be considered for data analysis:

Identify all the measurements in the form of mathematical numbers. In any process all the activities should be measured in numbers.

Specify the most dominant variables in the design. In any production processes there are variables that have a greater effect on process performance than others.

Determine variables that contribute to the sigma mean.

Identify the source of variation/root causes of defects.

When designing plastic molded parts, consideration should be given to aesthetics, functional process capabilities, and manufacturing constraints. All disciplines from product design to production phase should understand their roles in bringing the product to completion. There is an interrelationship between design, materials, and processes. Consequently, any decisions made by individuals and groups will profoundly effect functionality, process efficiency, tooling, assembly maintenance, engineering, and the total lifecycle of the product. Some of the factors that need to be considered are (1) design tolerance, (2) property consistency of material, (3) tooling capability, and (4) process capability.

Training metrics

This analyst is often confronted with situations wherein the processes are poorly understood – sometimes by the CM folks but more frequently by their internal customers. Too little time is spent/available for training the people involved in the CM processes. My recommendations almost always include dedication of more time/manpower for training. On occasion a comment will be made about the fact that training is expensive. I always agree, but point out that if one thinks training is expensive, try ignorance!

The CM managers and their key people should be spending a significant amount of time getting trained themselves and in training others. Unfortunately few benchmarks exist in this area but this analyst's experience would say that at least 10% of all CM hours available should be spent in training or giving training. CM folks should all keep track of those hours and the CM manager should total the time and report to themselves and the boss. In a larger company a full-time trainer to also coordinate and facilitate training is probably a wise investment.

Each person would have to keep track of time spent in and giving training and their total hours worked. What work is considered training should be defined – giving group presentations, one-on-one training, seminars, reading books or online, etc. The CM manager would summarize this data monthly. One good method of presenting this data is shown in Fig. 2.5.

This metric was labeled Bronze simply because there is no apparent need to distribute it beyond the CM group and their manager – who hopefully is the Chief Engineer. The trend in this case is positive. A goal should probably be set to achieve a total of at least 10% training time.

Another CM unique measurement might be time spent doing process audits. This could be a separate chart or added to the above chart. Each year at least one major process should be audited. Are the processes written, concise, clear, followed and measured?

4.2 Architecture of Human-Centered VMS

Our goal is to design and operate a manufacturing company so that it can serve both external customers (or the society) and internal customers (i.e., its employees). To meet this goal, we propose a Human-Centered Virtual Manufacturing System that will (1) expand human capabilities, (2) support human creativity, and (3) support collaboration among the people so that the responsiveness and teaming of the NGM Company are maximized.

We define a VMS as a “cyberspace structure of interface, planning, and control mechanisms to support human decision-making via monitoring & simulation of actual manufacturing situations through modeling of all activities and resources in a physical manufacturing system”. Furthermore, we regard a (narrow) manufacturing system to be composed of 1) a hardware system including tools, machines, facility, materials, parts, and products, 2) people including organizational structures, 3) a VMS, and 4) others including paper documents, company policies, etc. In this sense, the VMS is also a “real” part (as a decision support system) of the manufacturing system.

Shown in Figure 6 is a reference model of the Manufacturing Company in Figure 5, which we called a narrow manufacturing system. In this model,

OCS (Order Control System) consists of Marketing, Bidding & Negotiation, Delivery Control, and Post-Sales Services functions.

MES (Manufacturing Execution System) consists of Shop-level Process Planning, Loading Scheduling, Progress Control, and Logistics functions.

MPS (Manufacturing Preparation System) consists of Process Planning, Tooling, P/G, and Exception Handling functions. The Exception Handling function is responsible for facility maintenance, ECO (engineering change orders), trouble shooting, etc.

The Factory has machining, inspection and assembly stations as well as transportation and storage facilities.

The proposed VMS framework supports two types of VMS: Prototypic and Operational VMSs. As depicted in Figure 7, the Prototypic VMS is used as a virtual prototyping tool for designing a new manufacturing system. This concept is used widely in designing a new product, which is often called Digital Manufacturing. An Operational VMS may be obtained from the Prototypic VMS (for a new manufacturing system) or constructed from the scratch for an existing manufacturing system.

The Human-Centered VMS concept is geared to the Operational VMS. The Architecture of our Human-Centered VMS is presented in Figure 8. The Humans in the Physical Manufacturing Domain are hooked up to the VMS, and there are “high- speed” Data Transfer Lines connecting the VMS to the physical Factory and to the outside world (via Internet).

The VMS shown at the bottom of Figure 8 has four “virtual” sub-systems – Virtual MES, Virtual MPS, Virtual Factory, and Common DB – as well as User Interface Control and Data Handler. The overall structure of the VMS looks similar to the CIM Architecture of Figure 1, but its concept is quite different. In the case of CIM architecture, integration is achieved in a physical domain (with or without human involvement). In the VMS concept, integration is achieved in a virtual domain to serve the humans in the physical domain where teaming and human creativity are more important. That is, the role of VMS is to expand the capabilities of humans and support their creativity and collaboration efforts.

One Author and One Acceptor

Most companies have several engineering department signatures on release orders and change orders. Curiously, design drawings and specs are seldom signed by the internal customer and no one typically signs a parts list. Go figure!

For new documents, the best practice would have one author—the responsible design engineer and one acceptor—a technical representative from the primary internal customer. The object of this approach is to make responsibilities very crisp and clear—one responsible for the design and one for the manufacture. Each should call on others in or related to their discipline as needed before they approve.

For most design documents, the primary customer is manufacturing. For a product specification, it is probably marketing. For a test document, it might be quality assurance or test engineering. The operations management might assign a single function (such as ME or IE) to represent all departments—including even the supply chain. A manufacturing engineer or industrial engineer can be cognizant of both make or buy issues.

Based upon the company culture or organization structure, a separate signature representing the supply chain may be necessary when a purchased item is involved.

This practice need not take away the design managers’ right to manage. They can still review designs before release as needed. It merely places the burden for best practice where it belongs—with the cognizant engineer and the primary internal customer representative.

The same practice can be applied to the change process. Some changes would affect multiple documents and thus require a different signature as acceptor on the applicable document.

Thus, there is a need to document the specific author and acceptor responsibilities. This takes us back to the cognizant engineer list. That list, as previously stated, would contain the design, manufacturing, and others as needed for signing documents according to your policy.

Policy: Limit signatures on documents to an absolute minimum, but at least one author and one acceptor should sign.

It is universally believed by this consultant’s clients and seminar attendees that more signatures do not improve the quality of the outcome.

Consider the paradox wherein several people sign a drawing, drawing release, or change, while no one signs the parts list.

32.1 Design for Quality

Traditionally, quality conformance in the production process can be said to be Quality after design (QaD) viz, applying quality control procedures during the production process only to ensure that the product conforms to the specifications given by the designers.

In his book, Quality by Design, Juran propounded his theory of QbD contrary to the traditional QaD, and emphasized that that quality could be planned, and that most quality crises and problems relate to the way in which quality was planned. QbD provides guidance to facilitate design of products and processes that maximize the product’s efficacy and safety profile, while enhancing product manufacturability and control. It is defined by Business Dictionary as a systematic process to build quality into a product from the inception to final output.

Juran’s emphasis on the above concept, as well as Taguchi’s experiments at Toyota as explained in Chapter 31, made several automobile manufacturers rethink the way the design process for a product is conceived, by adapting the principle of Quality by Design (QbD), by which detailed planning and checklists shall be prepared, to highlight all the factors that affect the production. These factors must be considered and analyzed before embarking upon the design procedure. This detailed planning builds quality into the design process as highlighted by Juran.

This term, QbD, is now replaced by a more popular term, Design for quality (DFQ), which is complementary to DFSS (Design for Six Sigma). It may be noted that while Six Sigma emphasizes the improvement of the process to achieve higher levels of quality, DFSS emphasizes meticulous planning in the design stage itself. Thus, while the former adapts the Define, Measure, Analyze, Improve, and Control (DMAIC) methodology, the latter adapts the Define, Measure, Analyze, Design, and Verify (DMADV) methodology, which is described more in later paragraphs.

It may also be noted that several books, as well as several six sigma practitioners relate the DMAIC methodology to QbD as they do equally to the six sigma process. The following paragraphs describe DMAIC as the methodology for achieving six sigma levels.

While DMAIC is described in detail in Chapter 24, it is cited here again to provide a contrast with DMADV or DFSS.

Define the project goals and customer (internal and external) requirements.

Measure the process to determine current performance.

Analyze and determine the root cause(s) of the defects.

Improve the process by eliminating defect root causes.

Control future process performance.

This can also be represented below.

Define the problem/defects

Measure the current performance level

Analyze to determine the root causes of the problem/defects

Improve by identifying and implementing solutions that eliminate root causes

Control by monitoring the performance of the improved process

The process of DFSS can be understood better by some of its explanatory definitions.

A methodology for designing new products and/or processes.

A methodology for redesigning existing products and/or processes.

A way to implement the six sigma methodology as early in the product or service life cycle as possible.

A way to exceed customer expectations.

A way to gain market share.

A strategy toward extraordinary return on investments.

It may be noted that this procedure is broadly similar to any other method improvement procedure followed by industrial engineers, which is explained more in Section 22.9 of Chapter 22 on Kaizen.

Creating the PDS - the checklist

The creation of the PDS involves asking the right questions - if the answers are easy it is probably because the difficult questions have not been asked. These questions should be answered by the internal or external customer in broad functional terms to allow the designer freedom to innovate. A broad checklist of general points is shown on the right. These are designed simply to stimulate thinking and not all of the factors noted will apply to a given product but the subject headings should be scanned to give areas for profitable consideration. It is a series of questions to ask to enable the capture of the essential requirements for the product and not a rigorous design methodology.

The PDS for every project will be different. Creation of a standard format or generic PDS for the specific company requirements will make completion of the PDS rapid and will ensure that most of the points are considered.