qfd case study.pdf

(500 KB) Pobierz
QFD Case Study
QFD Case Study
Quality function
deployment (QFD)and
target costing case
study
QFD & TARGET COSTING CASE STUDY
Kenneth Crow
DRM Associates
© 2002 DRM Associates All rights reserved. May be used with attribution. Other use prohibited.
BACKGROUND
The company was under contractual obligation to deliver a quick release top nozzle
(QRTN) to several customers. This is a complex subassembly costing approximately
$1,700 each for a major piece of capital equipment. The current product, a removable top
nozzle (RTN), is needed in case a product has to be repaired because of a failure. While
this repair is a low probability occurrence, the cost of downtime is very high. If the product
can't be repaired within a reasonable period, there are significant operational costs
involved.
The current RTN allowed repair within a reasonable time if all things went according to
plan. However, there was considerable time and cost involved in mobilizing equipment to
support the repair, in setting up the equipment to support the repair, removing and
replacing the top nozzle, and tearing down and demobilizing the repair equipment. There
were additional problems as follows:
l
The nozzle did not always come free from the product as intended and an additional
heavy tool was needed to supply the force to lift the nozzle off.
l
Removal process involved taking out a locking tube, which resulted in a loose part.
There was concern that this part could drop during the removal or replacement
operation, taking additional time. Competitive designs did not have loose parts.
l
The removal and replacement process was not sufficiently reliable. There was one
occurrence when a locking tube was jammed into another locking tube, preventing
the assembly from being used.
In order to meet contractual requirements as well as develop a more competitive design for
other potential customers, a project was initiated to develop a QRTN. A previous QRTN
project was cancelled late in the Detailed Design Phase after the estimated cost increased
to a level significantly above the RTN cost (+80%). Additional contractual commitments
caused the company to restart the project after several years. A multi-functional core team
was created, and a decision was made to use the newly-developed NPD process, target
costing, value analysis, and quality function deployment (QFD) to help the team
accomplish its objectives. In preparation for this program, hands-on QFD, target costing
and value analysis training was provided to team members, several key functional
managers, and other potential users of these tools. In addition, a QFD consultant was
engaged to help the team apply these tools.
VOICE OF THE CUSTOMER
QFD logically begins with understanding customer needs and using these needs to drive
http://www.npd-solutions.com/qrtncasestudy.htm (1 of 10)6/16/2006 6:13:30 PM
258403745.001.png
QFD Case Study
the development process. These customer needs are referred to as "voice of the
customer" (VOC). Instead of solely relying on the marketing organization to define these
needs, team members met with customers to gain a first-hand understanding of their
needs. It was recognized that there were multiple customer voices to consider with this
project:
l
Voice of the Customer This is the obvious customer. They need to be satisfied that
the QRTN works reliably as intended, both in operation as well as during repair.
They also need to be assured that the repair can be done expeditiously, while on
the critical path. Understanding this VOC involved a review of contract
requirements, discussions with marketing personnel responsible for the accounts
that had contractual commitments for the QRTN, and discussions with the
customer's engineering personnel. Invitations were issued to two customers to have
their personnel participate on the core team, but the customers declined because of
the time commitment involved. They did ask to be regularly briefed on the progress.
Voice of Services Division The actual reconstitution work was done by the
Services Division, a sister division. As a result, they had important insights into the
needs to support the actual removal and reinstallation of the top nozzle. A Services
Division individual involved in this work was assigned to the core team to provide
this insight and support the development process.
l
Voice of the Engineer There are specific regulatory and interface requirements
with existing products that must be addressed and considered. Team members
familiar with these requirements provided this customer voice.
l
Prior to meeting with customers, the team obtained a briefing on the prior QRTN effort to
familiarize them with some of the issues. Meetings were scheduled with engineering
personnel at the customers that had a contractual requirement for the QRTN. The initial
meetings were intended to probe and primarily listen for the customer needs. A list of
questions to ask and a meeting agenda were prepared to guide these interviews. The
teams were briefed on asking "Why" to understand the fundamental customer needs.
Several team members were involved in each of these interviews, and they typically talked
with multiple people in each customer organization. Interview notes were summarized and
distributed to all team members. In addition, these meetings were discussed in detail in
subsequent team meetings to assure a complete understanding of each customer's
perspectives. Contractual requirements were reviewed. A teleconference with the
marketing representatives for the customers was held to gain their perspective.
The customer visits also provided good insight into the design of two of the competitor's
products and an in-house design from one of the customers. This proved to be a good
opportunity to gather competitive assessment information and provided the information to
develop rapid prototyping models and/or sketches of competitive joints.
To gain a better understanding of the voice of Services Division, the team watched a video
of the repair process to gain a first-hand understanding of the issues in top nozzle removal
and installation. Data was also assembled (Table 1) detailing the time requirements for
Services Division to perform its job with the RTN and estimates or goals with the QRTN.
Table 1 - Repair Time Analysis
http://www.npd-solutions.com/qrtncasestudy.htm (2 of 10)6/16/2006 6:13:30 PM
QFD Case Study
Activity
Current RTN Design
(3 people required)
Hours
QRTN Design Estimates
(2 people required)
Hours
Equipment Setup
10
2
Repair
10
3
Inspection
1
1
Top Nozzle Removal
2
0.5
Top Nozzle Installation
3
0.5
Post Repair Equipment Tear
Down
15
2
Total
41
9
The team met to compile all of the requirements. Brief natural language expressions of
customer needs (e.g., "maintain locked joint") were written on "post-its" and placed on the
wall. Some questions were asked to clarify meanings and to determine "Why". The team
used Affinity Diagramming to organize related statements into logical clusters. Besides
organizing the customer needs, this also facilitated the following:
l
Some redundancy in statements of need was observed and eliminated
A pattern was observed of some very detailed, lower-level needs mixed with higher-
level needs. This led to an attempt to "level" needs by asking "Why" and leading to
consolidation with higher level needs.
l
Related needs were discussed to understand the need. This led to the development
of a data dictionary.
l
Initially, there were thirty-three statements of customer needs. By organizing these
requirements with affinity diagramming, examining each of these requirements, and asking
"why" to understand the fundamental need, this list was consolidated into twelve customer
needs. Table 2 shows examples of this consolidation process.
Table 2 - Refining Customer Needs
Original Customer
Needs
Consolidated Customer
Need
Comment
Thimble rotation
resistance
Joint reliability during
repair
By asking "Why", consolidated
customer needs back to the basic
need.
Precludes skeleton
damage
No loose parts during
joint operation
http://www.npd-solutions.com/qrtncasestudy.htm (3 of 10)6/16/2006 6:13:30 PM
258403745.002.png
QFD Case Study
Simplified tooling
Simple tooling
Consolidated requirements
because simple tooling generally
would lead to lower cost and cost
was not deemed as important a
customer need. Couldn't directly
control mobilization with the
design, but concluded that simple
tooling would achieve this same
objective. Minimal removal force
also related back to simple tooling.
Low cost tooling
Minimize tool mobilization
Minimal removal force
Fast nozzle removal/
install
Fast repair
By asking "Why", consolidated
customer needs back to the basic
need. Many of these lower-level
needs then became technical
characteristics.
Repair on critical path
No loose parts during
joint operation
Minimum number of joints
Maintain alignment
during repair
At first, the team did not understand the value of the data dictionary. However, as
numerous questions came up over the course of this project, the data dictionary proved
invaluable. See the final data dictionary .
PRODUCT PLANNING MATRIX
Once these customer needs were identified, they were organized into a product planning
matrix . Based on the initial customer meetings, priorities were assigned to each
requirement using a 1 to 5 scale. The information gained on competitive products as well
as prior internal competitive assessments was used to look at competing joint designs from
a customer perspective and develop an initial Competitive Evaluation. Actual hardware,
rapid prototyping models, and sketches were used to support this evaluation. The
Competitive Evaluation was done for six joint designs: the current RTN design, the
previous QRTN design, a joint company/customer design, a customer design and two
competitor's designs. This information was reviewed with customers. They were satisfied
with the stated customer needs in the matrix. They provided feedback to make minor
changes to priorities and the competitive assessment.
The customer needs, priorities and competitive assessment were reviewed and a product
plan was developed. The next step was to develop technical characteristics of the products
to respond to customer needs. This was one of the most difficult steps for team members
and required a good deal of facilitation and thought. The criteria for the technical
characteristics were:
http://www.npd-solutions.com/qrtncasestudy.htm (4 of 10)6/16/2006 6:13:30 PM
258403745.003.png
QFD Case Study
l
Global - must not imply or constrain design alternatives to any one technical
solution or approach
l
Meaningful - must be subsequently actionable to drive the design process; they
can't be abstract
Measurable - must be able to define a target value and clearly determine whether
the characteristic has been achieved or not
l
As these technical characteristics were developed, their definitions were also defined in a
data dictionary to assure a common understanding among team members. Again, this was
referred to many times during discussions. Examples of the technical characteristics
defined in order to satisfy customer needs are shown in Table 3.
Table 3 - Technical Characteristics to Satisfy Customer Needs
Customer Need Technical
Characteristics
Discussion
Visually verify
locked joint
Joint verification time
The removal and installation process is
done under conditions where the joint can't
be directly seen, but is observed via video.
It is required to visually verify the joint is
locked upon reinstallation. This is
videotaped. The nozzle develops a black
coating in operation making visual
verification difficult. It was observed that the
contrast of new parts and having part
features that protrude above the surface
help with verification. However, stating
these as technical characteristics was not
global. Therefore joint verification time was
determined to be the most appropriate
technical characteristic.
Fast repair
No loose parts during
operation
A variety of factors support the customer
need for fast repair. Loose parts contribute
to additional handling time and potential
time if part is dropped. If lifting force is
greater than what a person can lift,
additional equipment and set-up time are
required. The two time-related criteria are
straight-forward goals. If protrusions exist
above adapter plate, additional time is
required to lift tool over protrusion to
properly seat the tool. The greater the OD
collet to insert clearance, the easier it will
be to access and pull parts of the product
that require replacement. Moveable tooling
parts may contribute to additional operation
time.
Operator lifting force
Joint lock verification time
Maximum removal
installation time
Protrusion above adapter
plate
OD collet to insert
clearance
No moveable tooling parts
http://www.npd-solutions.com/qrtncasestudy.htm (5 of 10)6/16/2006 6:13:30 PM
258403745.004.png

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika:

Zgłoś jeśli naruszono regulamin