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Portland State University Maseeh College of Engineering and Computer Science

Humidifying a Sealant Cure Oven

Product Design Specifications

Engineering Team: Thong Truong

Paul Lucas

Khoi Nguyen

Asgedom Gebrehiwot

Mircea Bec

Meshari Ebrahim

Academic Advisor: Faryar Etesami

Industry Advisor: Rory Olson

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Table of Contents

Introduction ............................................................................................................................................................................... 3

Explanation of This Document ........................................................................................................................................... 4

Mission Statement ................................................................................................................................................................... 4

Project Plan ................................................................................................................................................................................ 4

Identification of Customers ................................................................................................................................................. 5

External ................................................................................................................................................................................... 5

Internal .................................................................................................................................................................................... 5

Customer Feedback and Interviews ................................................................................................................................ 5

Initial Interview .................................................................................................................................................................... 6

Product Design Specifications (PDS) ............................................................................................................................... 7

High Priority .......................................................................................................................................................................... 8

Medium Priority ................................................................................................................................................................... 8

Low Priority ......................................................................................................................................................................... 9

Not Applicable ................................................................................................................................................................... 10

House of Quality ..................................................................................................................................................................... 11

Technical Risk Management ............................................................................................................................................. 11

Scope definition .................................................................................................................................................................. 12

Performance ........................................................................................................................................................................ 12

Reliability .............................................................................................................................................................................. 12

Conclusions .............................................................................................................................................................................. 13

Appendix I – Project Timeline .......................................................................................................................................... 13

Appendix II – PDS Checklist .............................................................................................................................................. 15

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Introduction Boeing design aircrafts which resist corrosion through the use of proprietary corrosion inhibiting sealants. The proper application of sealant directly affects the quality and reliability of Boeing’s aircraft. This process is essential in order to control corrosion to a manageable level and therefore not jeopardize the intended load carrying capability of the airplane. Sealing for corrosion prevention must be achieved under the appropriate conditions or problems requiring extensive maintenance and cost may occur while in service.

Boeing uses a two-component, room temperature curing, polysulfide sealant containing corrosion inhibiting chromates to effectively eliminate corrosion. The two current approaches of curing the sealant are the “traditional” and “lean” methods.

Figure 1: The “Traditional” oven. Figure 2: The “Lean” oven. Compact in size.

The traditional method utilizes large curing ovens (Figure 1). Although these ovens allow for humidity control (accelerating the curing process) the ovens are not equipped with corrosion resistant materials and are therfore heavily corroded. These ovens are large monuments that require dedicated wiring and plumbing and are therefore costly to move. These enormous sizes also contribute to poor flow conditions and temperature stability.

The more recent “lean” method utilizes much smaller ovens (Figure 2) offering better flow conditions and temperature stability. The small dimensions and power requirements (120 Volts at 60 Hz) allows the machine to be moved with relative ease and be located wherever a typical wall outlet can be found. These ovens are not equipped with humidity control and also require fixed plumbing.

Method Advantages Disadvantages

Lean Proper Flow

Not Hardwired

No Humidity Control

Plumbed

Traditional Humidity Control Large Size

Hardwired/Plumbed

Table 1: List of current methods, their advantages and disadvantages

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Explanation of This Document This Product Design Specifications (PDS) report defines the external and internal customers, the project requirements, design constraints, and the priority of those constraints. In addition, it defines the criteria and considerations for the design of the Humidity Controlled Oven device. Also, it specifies the customer base for the device as well as important design requirements and objectives. Priority will be assigned to each need as well as engineering metrics, targets and methods of evaluation. A house of quality is also included.

Mission Statement The goal of the Boeing capstone design team is to design a product that embraces the advantages of each of the current methods and combines them into a highly efficient curing oven. The disadvatages previously discussed, summarized in Table 1, are the foundations upon which th project specifications have been built. In redefining the current “lean” method we strive to equip the current ovens with a non-corrosive, humidity controlled environment while maintaining the lightweight design. These ovens will have on board water supplies allowing for a modular design.

Project Plan The dates in the following table are goals and deadlines for completion of project milestones. Please refer to Appendix I for the project calendar.

Project Milestones

Task Start Date Finish Date Due Date

Initial Brainstorming Jan 9 Jan 28 -

PDS Report Jan 9 Jan 28 Jan 30

External Search Jan 20 Feb 1 Feb 27

PDS Report Presentation Jan 30 Feb 13 Feb 13

Initial Design Feb 3 Feb 20 -

Design Feb 20 March 10 -

Design Evaluation March 10 March 12 -

Progress Report Jan 30 March 10 March 12

Progress Report Presentation

Feb 20 Feb 25 Feb 27

Prototype & Test April 2 May 2 -

Redesign May 2 May 10 -

Repeat Prototype & Test May 10 May 17 -

Manufacture May 17 Jun 1 -

Assemble/Install/Test Jun 1 Jun 10 -

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Identification of Customers This section identifies those customers affiliated with the Boeing capstone design team. They are those

who influence/establish the product design requirements. They have been classified below as either

internal or external to the design team.

External External customers are those who are not affiliated with Portland State University. The following lists

those that have had input on design considerations.

The Boeing Company o The method of sealant must remain user friendly, safe, and reliable o The manufacturing of ovens must remain relatively un-costly

Rory Olson, Boeing Research and Development Engineer

o The temperature must be monitored and remain within the given requirements o The humidity must be monitored and remain within the given requirements o Flow control must allow for an effecient sealant and curing process o The device must be designed in an ergonomic manner o Parts should be designed to be easily replaced and maintained o Parts should be durable to extend life of service o The weight should remain reasonable to allow for easy transport o The device will allow for scaling up or down depending on oven size o The finished components must test tack free o The finished product must contain no silicon products and avoid condensation of water

on parts.

Internal Internal customers are those that are affiliated with Portland State University’s capstone team. The

following lists those that have had input on design considerations.

The Portland State Capstone Program o The capstone team designs, manufactures, analyzis, and verifies the final product

Dr. Etesami, Mechanical Engineering Capston Coordinator

o Design reports must be produced o Design presentations must be given o Weekly progress meetings must be attended and contructive

Capstone Team Members

o The final design must exhibit the teams technical ability and knowledge

Customer Feedback and Interviews The capstone team met with Rory Olson, a research and development engineer at Portland’s Boeing

facility. A tour of the facility was conducted in order for the members of the team to better understand

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the manufacturing, assembly, sealing and curing processes. Rory was present during and after the tour

to answer any questions and provide feedback for possible design solutions.

Initial Interview Rory detailed the reasons behind the curing process while explaining the current methods used and

some of the problems associated with them. The importance of tack-free time and curing time was

explained. The tack-free time being defined as the time by which the sealant is no longer sticky to touch

whereas the cure time being the time necessary for the sealant to cure to a specific hardness.

The influence of temperature and relativity humidity on curing time was explained and tolerances were

given. A temperature envelope of 130 oF to 135 oF is currently maintained which is also the goal of the

final design. Temperature below this range increases curing times whereas; above this range causes

part failure due to sealant entrapment. Rory explained that a 50% relative humidity with a tolerance +/-

5% could accelerate the curing process, however if the humidity is too high it will discolor and damage

the sealant and force a rejection. If it is too low there is no added benefit, but no problems are caused.

The negative interaction between silicon products and Boeing’s proprietary sealants was stressed in

order to bring to light the importance of not using such products in final design.

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Product Design Specifications (PDS) Based upon the interviews and input from Rory the following product development specifications have

been detailed in the tables below. They are classified by priority level (high, medium or low) and given

page numbers in the table following immediately. The pages below present, in further detail, the

specifications by requirements, customer, metrics, verifications, basis, and target values.

Product Design Specifications

Criteria Priority Page Performance High 8 Quality and Reliability

High 8 Life in service High 8 Materials Medium 8 Dimensions Medium 8 Testing Medium 9 Documentation Medium 9 Timelines Medium 9 Environment Low 9 Maintenance Low 9 Weight Low 10 Ergonomics Low 10 Cost of production per part (material and labor) N/A 10 Competition Products N/A 10 Shipping N/A 10 Packaging N/A 10 Aesthetics N/A 10 Legal (Related patents) N/A 10 Disposal N/A 10 Legend: High Priority Medium Priority Low Priority Not Applicable

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High Priority:

Quality and Reliability

Primary Customer Requirement Metrics Target Basics Verification

Boeing Part Failure - 1 per 1000 Customer Feedback Testing

Life in Service

Primary Customer Requirement Metrics Target Basics Verification

Boeing

5 years continued operation

Years

5 years

Customer Feedback Design

Medium Priority:

Dimensions

Primary Customer Requirement Metrics Target Basics Verification

Boeing Must be 3’×3’×4’

chamber with one opened-end

Varied with different

parts Variable Size Customer Feedback Design

Performance Primary Customer Requirements Metrics Targets Basis Verification

Boeing Humidity Relative

Humidity 50%RH±5%

Customer Feedback

Prototyping

Boeing Temperature Degrees oF 130±5°F Customer Feedback

Prototyping

Materials

Primary Customer Requirement Metrics Target Basics Verification

Boeing No part interaction

with Silicon or water

- No

interaction

Group Decision with Customer’s Input and Requirement

Design

Boeing Corrosion Resistance

- Corrosion resistant metals

Customer Feedback Design

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Testing

Primary Customer Requirement Metrics Target Basics Verification

Project Team Testing +/- Works as intended

Group Decision

Study of Testing Analysis

Documentation

Primary Customer Requirement Metrics Target Basics Verification

Boeing/PSU PDS, Progress, Final Reports

Deadline Meet the deadline

Department of ME

Grade

Timelines

Primary Customer Requirement Metrics Target Basics Verification

ME 492 PDS/Progress

Reports Submitted

Reports 2 reports

Course Requirement

Grade

ME 493 Design Report Submitted

Reports 1 report

Course Requirement

Grade

Boeing Completed design

and prototype Fully

functional Meet the Deadline

Customer Feedback and

Course Requirement

Grade and Experience

Low Priority:

Environment

Primary Customer Requirement Metrics Target Basics Verification

Boeing

Operating process with

clean, purified oven

Contamination of

surroundings

No detectable contamination

to the environment

Customer Feedback

Material and Process Record

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Maintenance

Primary Customer Requirement Metrics Target Basics Verification

Boeing Minimum

maintenance Maintenance

Interval 1 week

Customer Feedback

Similar System Comparison

Weight

Primary Customer Requirement Metrics Target Basics Verification

Boeing Light Weight Pounds 200 ± 50 lbs

Group Decision with Customer’s

Input

Measurement

Ergonomics

Primary Customer Requirement Metrics Target Basics Verification

Boeing Weight Limit

of Water Supply

Pounds 35 lbs Customer Feedback

Measured

Not Applicable: Not Applicable

Criteria Reasons

Cost of production per part (material and labor) Boeing’s responsibility

Competition Products Not applicable

Shipping The part is installed and operated at Boeing facility.

Packaging None required

Aesthetics None required

Legal (Related patents) Legal constrains and patents controlled by Boeing

Disposal None required

Applicable Codes and Standards Not applicable

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House of Quality In the following table are listed the highest priority parameters with selected engineering criteria that are expected to influence the final performance

Parameter

Imp

ort

an

ce

Cu

sto

me

r

Engineering Criteria Competition

Te

mp

era

ture

(oF

)

Hu

mid

ity

(% R

H)

Co

st

($)

Po

we

r

So

urc

e

(Vo

lts

AC

)

We

igh

t

(lb

s)

Flo

w

Co

ntr

ol

Wa

ter

Su

pp

ly

Cu

rre

nt

De

sig

ns

Performance 10

Boeing

***** ***** - - - *** - **

Mobility 6 - - **** ** ** ***** *

Testing 9 ***** ***** - - - ** - -

Maintenance 7 - - **** - - - - -

Ergonomics 2 - - - - *** - **** **

Installation Project Team - - ** **** * - ***** -

Current

Design _ 135 N/A N/A 120 200 No N/A -

Target _ 135 50% 2000 120 300 Yes Portable -

Legend: Each criteria is given an influence rating relative to each parameter ranging from * meaning little to no known influence to ***** meaning critically influential.

Technical Risk Management In order for the successful completion of this project steps must be taken to prevent failure. This process aims to manage all foreseeable risks in an effective and proactive manner, in order to maximize the probability of the project achieving its objectives. This process is dynamic and will cover all activities undertaken during the projects lifetime. The tables below define the current foreseeable risks and may be adapted as the project progresses.

RBS LEVEL 0 RBS LEVEL 0 RBS LEVEL 0

0. PROJECT RISK 1. TECHNICAL RISK

1.1 Scope definition

1.2 Performance

1.3 Reliability

In order to establish the probability and impact of any risks the metric below (Figure 2) will be used to analyze each risk. This will allow the group to keep track of any costs, loss of time, or quality loss associated with each risk. Again, this list is dynamic and may be adapted accordingly.

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SCALE PROBABILITY IMPACT ON PROJECT OBJECTIVES

Very High >90% Time Quality

High 50%-90% 4-10 days Very significant impact on functionality

Medium 30%-50% 1-3 days Significant impact on functionality

Low 10%-30% <1 day Minor impact on functionality

Negligible <10% No change No changes in functionality

Scope definition It is important that incremental expansion of the scope of this project is minimized. The complex nature and the time allowed for completion of the device does not allow for an ever-increasing list of added features.

It is for this reason that the scope of the project is properly defined. In order to achieve this the needs and expectations of our project stakeholders have been properly identified and prioritized as may be seen in the Project Development Specifications above.

In order to address this problem a “scope control process” will be maintained throughout the lifetime of the project. Any changes to the project will be funneled through this process for evaluation. For this reason any deviation or change of plan must be brought to the attention of the Project Manager and discussed with the group as a whole before any corrective action is taken.

Performance The given deadline requires that the tasks and schedule for the project be properly defined and followed in order to produce the deliverable. As the project requires the successful completion of tasks from several individuals it is important for the Project Planner and each member of the team to know if the project is veering off track.

To maintain a steady progress, performance measures will be used to identify the success rate of each member and the team as a whole. For this reason it is imperative that the expectations for each task assigned be well defined. The tasks will be assigned as a group and the performance of each member’s task will be weighed against the expectation upon its completion.

Reliability It is required that the end product produce reliable results. As the device will be used on a daily basis it is imperative that it performs consistently. Failure to meet this requirement will prove the project unsuccessful, as the cost associated with part failure is high.

For this reason an effective reliability program will be put in place and incorporated into the overall systems engineering and design effort. Testing will be conducted frequently in the product development stage to identify any design weaknesses and eliminate or minimize their effects. A strong quality assurance program will also be implemented during manufacturing and production to translate the design into an actual system with great accuracy.

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Conclusions Boeing has been able to design their aircraft with corrosion prevention and control in mind by

understanding the causes and types of corrosion and taking measures to prevent it from occurring.

Through material, finish, and sealant selections as well as application of corrosion inhibiting chromates

and proper curing techniques, Boeing has increased the in-service lifespan of their aircraft. The sealant

curing process plays a pivotal role in the success of aircraft components. Boeing is looking to improve

the efficiency of the manufacturing process by re-designing the sealant curing process.

The current methods used are inefficient in nature and do not allow for proper flow control of

components. The large corroded ovens are costly to maintain, run, move and do not allow for proper

flow control. Smaller ovens have been put in place however, they lack humidity control and are costly

to move as the requirement fixed plumbing systems and are hardwired.

The Boeing Capstone Team will improve the curing process by equipping the ovens with humidity

control devices and portable water delivery systems. These systems will remain lightweight and

modular by way of material selection and power requirements. Correct placement of components and

selection of materials shall improve upon product lifetime and ease of maintenance. These

improvements will be made within the time and monetary limitations provided by the internal and

external customers.

The successful completion of this project will witness the elimination of current disadvantages in

Boeing’s curing process. In streamlining the curing method Boeing will continue to improve upon

corrosion control processes, helping further next generation design of aircraft.

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Appendix I – Project Timeline Humidity Controlled Oven

Time Line 01/25/2012

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Appendix II – PDS Checklist Criteria Pages

Performance 3,5,7,8

Quality and Reliability 3,5,7,8

Life in service 8

Maintenance 9

Materials 8

Size and Shape 8

Applicable codes and standards 10

Testing 9

Company constraints and procedures 3,5,6,7

Documentation 9

Timelines 4, Appendix I

Environment 9

Weight 10

Ergonomics 9,10

Maintenance 9

Cost of production per part (material and labor) 10

Competition Products 10

Shipping 10

Packaging 10

Aesthetics 10

Legal (Related patents) 10

Disposal 10