Pump S Vibration Absorption
2011
PRODUCT DESIGN SPECIFICATIONS REPORT
Sponsoring Company:
Edwards Vacuum Ltd
Contact Engineer:
Mark Romeo
Advisor:
Dr. Dave Turcic / Team Members:
Ron Pahle
Khoa T. Tran
Duc M. Le
Thanh Q. Nguyen
Shafi ?
Table of Contents
1. Project Background 3
2. Purpose of the Product Design Specification Document 3
3. Mission Statement 4
4. Project Plan 4
5. Customer Identification 4
6. Customer Interview and Feedback Summary 4
7. Product Design Specification 5
8. House of Quality 7
9. Conclusions 7
10. Appendix 7
11. Glossary of Terms 7
1. Project Background
Undesired noise and vibrations are a major problem in many engineering activities and domains. At Edwards Vacuum Ltd., vibrations from vacuum pumps present problems to their customers at Intel Corp. Multiple vacuum pumps are used for atmospheric control in sensitive manufacturing processes such as microchip fabrication. These vacuum pumps are seated on a rigid steel frame within a limited space requirement (Fig. 1). These pumps propagate vibration waves through the rigid frame to the floor and other piping fixtures attached to the frame. Those vibrations add unwanted noise which adversely affects the microchip fabrication operations at Intel.
Vibration isolation can be passive, active or semi-active. Passive vibration isolation is implemented by proper structural design to make sure the optimal dynamics properties, namely the stiffness and damping properties, are achieved. Active vibration isolation can be performed by measuring the sources of vibration and generate a controllable force to compensate that vibration. Active vibration isolation involves typical feedback control systems which require sensors, micro-computers and power actuators. Semi-active vibration isolation is also an active control system but instead of generating power to the structure, this type of system seeks to control the damping and/or stiffness dynamically through the use of innovating material like magnetically active fluids or piezoelectric components. This approach results in less power consumption and higher space constraints. All approaches will be explored, discussed and evaluated on the criteria of cost, performance and space requirements.
2. Purpose of the Product Design Specification Document
The product design specification document must clearly define design criteria, metrics, targets, priorities and customer needs. Some prominent criteria include: cost, percentage reduction in vibration, size and service life. A detail list of criteria is provided in Appendix A. The team and our customer are to agree on this document as a principal guideline for product delivery. This document will be referred to in case of dispute over product’s performance or related issues.
3. Mission Statement
Derive a solution to minimize the vibration propagated from the pump system through the steel frame and surrounding workplace. This is meant to reduce any interference the pumps vibration has on sensitive manufacturing equipment above the pumps. There are a variety of constraints that will be addressed including seismic regulations, environmental cleanliness, and space limitations. Our customers for this solution will be Edwards Vacuum Ltd. and their correspondents at Intel. The solution will be needed for full scale testing by May ?, and a finalized design to be due on June ?.
4. Project Plan
The details of the projects timeline are detailed in the Gantt Chart which is shown in Appendix B. This timeline was constructed based on deadlines provided by ME492 and by Mark Romeo of Edward Vacuum Ltd.
The main features of this plan include the Product Design Specifications, External and Internal Research, Design Evaluation, Prototyping, and Evaluation.
5. Customer Identification
The main external customer of this project is Edwards Vacuum Ltd. The other external customers are companies that operate the system and machine technicians responsible for operation and maintenance of the pump system.
The main internal customer of the project is capstone courses ME 491/492/493. Other internal customers are PSU department advisors and team members.
6. Customer Interview and Feedback Summary
The initial meeting with the sponsor took place during the ME 491 course. Another meeting and tour at Edwards Vacuum’s facility was held later, where the general design specifications were discussed. Some technical and functional requirements were determined in the interview with Mark, engineer from Edwards Vacuum Ltd as followed:
- The system must reduce vibration from the pump to the ground and from the pump to the pipes.
- The vibration absorbing system needs to be compact enough to fit the size of the existing frames.
3. The system should work for a variety of pump speeds (frequencies from 30 – 150 Hz).
7. Product Design Specification
The Product design specification is the most important part of this report. In this section, all the criteria related to the product are listed down with their priority. Those criteria has been discussing and developing by the team basing on requirements from sponsor as well as advices from expert. The idea of this PDS is to help describe the general picture of how the final product would be.
Criteria / Priority / PagePerformance / High / 5
Environment / High / 5
Life in service / Low / 5
Cost of production per part / Medium / 6
Size / Medium / 6
Weight / Low / 6
Maintenance / Low / 6
Installation / High / 6
Ergonomics (Ease of operation) / Low / 6
Materials / High / 6
Quality and Reliability / High / 6
Documentation / High / 6
Competition products / Medium / 6
Timelines / High / 6
Table 1: Applicable PDS criteria and page.
Legend: High priority Medium priority Low priority
PERFORMANCEPriority / Requirement / Customer / Metrics / Target / Target basis / Verification
Vibration reduction / Edwards / % / 25-75 / Edwards required / Prototype
Power consumption / Edwards / Watt / 0 / Edwards required / Prototype
Ease of use / Edwards / N/A / Totally passive operation / Edwards required / Prototype
Life in service / Edwards / Years / 10 / Edwards required / Design
ENVIRONMENT
Priority / Requirement / Customer / Metrics / Target / Target basis / Verification
Clean room compatible / End user / yes/no / Clean room qualified / End user required / Design
Eco friendly product / Self / yes/no / Green material / Self interest / Design
SIZE, SHAPE AND WEIGHT
Priority / Requirement / Customer / Metrics / Target / Target basis / Verification
Size / Edwards / yes/no / Fitting within the frame / Ergonomic / Prototype
Weight / Edwards/
Self / lbs / < 100 / Product portability / Prototype
INSTALLATION AND MAINTENANCE
Priority / Requirement / Customer / Metrics / Target / Target basis / Verification
Time to assemble/disassemble / Edwards / Minutes / < 15 / Product complexity/
Edwards required / Prototype
Tool requirement / Edwards / Number of special tool / 0 / Product complexity/
Edwards required / Prototype
Mechanical compatibility / Edwards / Yes/No / Yes / Edwards required / Prototype
Maintenance frequency / Edwards / Number of maintenance per 10 years / 0 / Edwards required / Testing
MATERIAL
Priority / Requirement / Customer / Metrics / Target / Target basis / Verification
Clean room compatible materials / End user / Yes/No / Clean room qualified / End user required / Design
Reasonable price / Self / N/A / Inexpensive / Budget / Design
Easy to machine / Self / N/A / Can be machined in the machine shop / Self/Expert / Prototype
COST
Priority / Requirement / Customer / Metrics / Target / Target basis / Verification
Price per pump / Edwards / $ / < 1000 / Edwards required / Design
Testing equipment / Self / $ / < 3000 / Budget/Expert / Testing
DOCUMENTATION
Priority / Requirement / Customer / Metrics / Target / Target basis / Verification
PDS / PSU / Deadline / PSU / Report
Progress report / PSU / Deadline / PSU / Report
Final report / PSU/
Edwards / Deadline / PSU/Edwards / Report
Timeline / Self/
Edwards / Deadline / Self/Edwards / Report
8. House of Quality
9. Conclusions
10. Appendix
A. PDS
B. Gantt Chart
11. Glossary of Terms
Because design specifications are highly specialized and technical documents, a glossary of terms affords a consistent application of the technical language.