Demonstration Test Plan for Reliability of Big Equipment

AgaWr

Registered
#1
Hi, I've found information on this forum very valuable. It helps me finding answers to topics I've been struggling for a while.

I have concern similar to bcoolnow. (see this thread starting at post #45) I want to perform the demonstration test for reliability but I am no longer sure that what I am thinking is wright. There is a component I want to test for reliability. Its working time is 10 years and I need to perform a test for a 90% reliability at 30 weeks time. A confidence level required is at least 90% and I don't want to have any failures. The sample size I am getting are high and I don't think it's feasible for my test. Well, maybe it is feasible and I understand the need for it but if I have time limitations and have only few samples available it looks like impossible to complete! :) Is there a rule for big machinery components like motors, pumps, etc...?
Thank you very much for any help.
 
Last edited by a moderator:
Elsmar Forum Sponsor

Miner

Forum Moderator
Staff member
Admin
#2
Re: Confidence & Reliability - Reference to a 90/95 Confidence & Reliability Level

Do you have any historical data regarding the shape parameter for these components? You will need this for your demonstration test plan.

Normally the test plan is a balance of samples and test time. If you are constrained on sample size, you test longer. If you are constrained on time, you test more samples. If you are constrained on both time and samples, you punt :). You can try an accelerated demonstration test plan. This requires more assumptions about the acceleration model. Some typical acceleration factors are duty cycle, temperature, load applied, etc.
 

AgaWr

Registered
#3
Re: Confidence & Reliability - Reference to a 90/95 Confidence & Reliability Level

Thank you for such a quick reply!

Yes, I believe I am struggling with the balance. I don't have historical data for the shape parameter but I chose 1 as I want to simulate the time up to the wear point when the curve starts to increase.
But I think it may be a good option to perform the accelerated demonstration test plan as you suggested. The machine is being used in time intervals and the service life is planned for 10 years. I want to perform the accelerated test for reliability and I have 26 weeks for that. I plan to apply an increased load (60%) as a stress factor. Do you think it can work? Are there other factors I should consider?
 

Miner

Forum Moderator
Staff member
Admin
#4
Re: Confidence & Reliability - Reference to a 90/95 Confidence & Reliability Level

What type of failure modes do you experience? A shape factor of 1 implies 100% random failures due to overload stress. If your product fails due to any type of wearout, you should use a shape factor > 1.

Load is definitely one means of accelerating failures. Temperature is another. If your product is not used 100% of the time, you can accelerate by increasing the duty cycle. You can also combine 2 or more means of acceleration. You will also need to define the accelerating relationship for each. For example, duty cycle is usually linear while temperature is often Arrhenius.
 

AgaWr

Registered
#5
Re: Confidence & Reliability - Reference to a 90/95 Confidence & Reliability Level

Hi,
This is a new product, however I can expect that potential failure modes would be diaphram deformation, motor failure, bearing failure.They are in order to what is expected to fail first.
I will definitely use shape factor >1 as the probability of wear increase over the time.

I have few option how to accelerate the test:

1. Duty cycle,
2. Load (motor speed),
3. Temperature (result of increase first two)

Can you advise what are the rules to define the acceleration relationship for various accelerations?

Thanks!!
 

Miner

Forum Moderator
Staff member
Admin
#6
I split these posts off into a separate thread. The two intertwined topics were getting confusing.

Duty cycle is usually a linear relationship. That is if normal usage is 2 hours per day, and you run it 12 hours a day, your acceleration factor is 6 (12/2 = 6). However, you must be careful if your product is intermittent duty instead of continuous duty. I doubt this is the case in your scenario.

Load is product dependent. Two likely models are Arrhenius and Power models. The former is temperature driven, the latter is voltage, current, speed, or power driven. Motor insulation is often Arrhenius. Bearing failures are often power models.

Increasing temperature is an Arrhenius relationship.

What is the diaphragm and how is it deformed?
 
Thread starter Similar threads Forum Replies Date
A Accelerated Reliability Demonstration Test Reliability Analysis - Predictions, Testing and Standards 4
T "Time of Demonstration" requirement for Reliability Test Reliability Analysis - Predictions, Testing and Standards 1
T Reliability Lifetime Requirement Demonstration Test Reliability Analysis - Predictions, Testing and Standards 3
D Demonstration Reliability Test Formula with allowance for 'x' Failures Reliability Analysis - Predictions, Testing and Standards 6
A Demonstration of Equivalence - Need for comparing biological characteristics for an SamD EU Medical Device Regulations 1
M Exemption Clauses for Research, Demonstration, etc. Other Medical Device Regulations World-Wide 2
TheMightyWife Clinical Evaluation MEDDEV 2.7.1 Rev 4 demonstration of equivalence EU Medical Device Regulations 6
B Israel Demonstration Medical Device Requirements Other Medical Device Regulations World-Wide 5
R Exporting to Korea a demonstration only medical device Other Medical Device Regulations World-Wide 2
W Medical Device Manufacturer Demonstration Equipment Other US Medical Device Regulations 6
D CE Marking for Demonstration / Evaluation Boards CE Marking (Conformité Européene) / CB Scheme 2
A Sale of Demonstration Units - How should we document it from GMP standpoint? 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 3
Howard Lee Electronic Approval Demonstration - Use of the voting option in Outlook Document Control Systems, Procedures, Forms and Templates 17
G Production rate demonstration? APQP Manual 4.1 ? Significant Production Run APQP and PPAP 7
J Best/Worst Production Demonstration Runs (PDR) - Share yours Manufacturing and Related Processes 3
B Demonstration of auditor competence. General Auditing Discussions 10
M Par.5.6.1 Demonstration of suitability, adequacy and effectiveness of QMS ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 4
Marc Demonstration Of Pavlov's Theory of Bureaucracy Philosophy, Gurus, Innovation and Evolution 1
E MSA for Push and Pull test Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 5
Z IEC 60601-2-25; Frequency response test Medical Device and FDA Regulations and Standards News 0
J Confusing on Harmonic Emissions/Voltage Fluctuations/Flicker test for CISPR 11 Class A Equipment IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
E Routine production tests - dielectric voltage withstand test IEC 60601 - Medical Electrical Equipment Safety Standards Series 4
D Test Method Validation Qualification and Validation (including 21 CFR Part 11) 4
Crimpshrine13 Laboratory Scope - Calibration vs. Test Methods - IATF 16949 IATF 16949 - Automotive Quality Systems Standard 3
N IEC 60601-1-1 - Stress test, reference voltage IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
R Accelerated Aging - Creating test samples - Implantable medical device Question Other Medical Device Related Standards 4
E Mentor for Test Method Validation (TMV) Design and Development of Products and Processes 2
L ASQ's Biomedical Auditor Course Test ASQ - American Society for Quality 1
W Regarding Requirement for Hi pot & Leakage Current test Station Set-up IEC 60601 - Medical Electrical Equipment Safety Standards Series 6
R Regulatory Affairs Certification (RAC) prep - Practice test versus actual exam Professional Certifications and Degrees 0
R SAT (System Accuracy Test) temperature according to AMS2750E AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 1
R MSA for ATE (Automatic Test Equipment Embedded Software) Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 9
D Test summary report example for design validation wanted - ISO 13485 ISO 13485:2016 - Medical Device Quality Management Systems 1
S Documenting Design Verification Test Results (ISO 9001) Design and Development of Products and Processes 1
A Earth leakage current test for Permanently installed Large scale MEE IEC 60601 - Medical Electrical Equipment Safety Standards Series 5
A Bench test report translation to English for 510(k) submission Other US Medical Device Regulations 2
J Production Line Test Brasil - High Voltage Dielectric Strenght Test Other Medical Device Regulations World-Wide 5
W Seeking Guidance Verification Test Strategy for Class B Medical Devices IEC 62304 - Medical Device Software Life Cycle Processes 1
J 510(k) for a control kit for an external IVD test kit 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 1
K Cord anchorage pull test IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
A IEC 60601-1 Dielectric Strength test for battery operated devices IEC 60601 - Medical Electrical Equipment Safety Standards Series 3
M Minitab assistant: 1-Sample % Defective Test Using Minitab Software 1
N Is capability applicable for a destructive test? Capability, Accuracy and Stability - Processes, Machines, etc. 9
JoCam Failure to test Class I medical device to IEC 60601-1-11 IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
K Dielectric strength test as per IEC 60601-1 -Infant incubator IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
M Test method validation - Is MSA (MSA1, MSA2, MSA3 and linearity) a good solution? Medical Device and FDA Regulations and Standards News 1
B Operator protection - When to apply table 7, Dielectric strength test voltage IEC 60601 - Medical Electrical Equipment Safety Standards Series 0
R Medical Device Airworthiness, DO-160 Test Planner IEC 60601 - Medical Electrical Equipment Safety Standards Series 0
J Audit Finding For Not Retaining Test Results ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 7
W ASTM F1929 dye penetration test - Validation for in-house testing ISO 13485:2016 - Medical Device Quality Management Systems 13

Similar threads

Top Bottom