SBS - The Best Value in QMS software

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
H 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
P Burst Test Acceptability Criteria ISO 13485:2016 - Medical Device Quality Management Systems 2
A 60601-1 clause 8.11.3.6 Test Clarification IEC 60601 - Medical Electrical Equipment Safety Standards Series 0
E Test report to certify compliance with IEC 62304 IEC 62304 - Medical Device Software Life Cycle Processes 3
E Tensile test machine, tinius olsen 602 Manufacturing and Related Processes 1
M Test failure Root cause not found Customer Complaints 10
Moumen H Variations between ASTM A29 Standard for steel bars and Mill test certificates specs Manufacturing and Related Processes 1
D Tip test 10° -> 5° IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
M Sponsor name presented in the test report EU Medical Device Regulations 4
M Packing Validation & Accelerated Aging Test ISO 13485:2016 - Medical Device Quality Management Systems 2
S OEM full range calibrations vs Validation special test points Medical Device and FDA Regulations and Standards News 0
C IEC 60601 - 8.8.3 Dielectric Strength test. 4kv being applied to the ground conductor?! IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
S Shelf Life Test for IFU and Implant Card Other Medical Device Related Standards 1
S Mechanical Test Under FDA Freedom of Information Act Medical Device and FDA Regulations and Standards News 5
S Critical characteristic on manufacturing operations test procedure Inspection, Prints (Drawings), Testing, Sampling and Related Topics 0
R IEC 60601-1 Clause 15.3.2, Push test IEC 60601 - Medical Electrical Equipment Safety Standards Series 0
S Knee Implant (Femoral -Cobalt chrome)-Sub chronic toxicity test (ISO 10993-11)choice of root Medical Device and FDA Regulations and Standards News 2
A Defining a lower ESD test level in IEC 60601 safety test IEC 60601 - Medical Electrical Equipment Safety Standards Series 5
N Is there a need for clinical test of Class IIa products (for MDR)? EU Medical Device Regulations 2
A Is calibration of test weight required General Measurement Device and Calibration Topics 4
S Non parametric test for semi-quantitative data. Statistical Analysis Tools, Techniques and SPC 5
Ed Panek Disaster Recovery Test IT (Information Technology) Service Management 3
A How much does a complete biocompatibility test package cost? Other ISO and International Standards and European Regulations 1
M Is it normal / sufficient to have only the IEC 60601-1-2 test report without indicating IEC 60601-1? IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
Z Is Op Amp Common-Mode Rejection Ratio (CMRR) test applicable to battery operated devices? Other Medical Device Related Standards 0
E When to perform accelerated aging studies and transport test(OQ or PQ) Qualification and Validation (including 21 CFR Part 11) 4
U Does *anyone* know a lab that will test to EN 455-4 Medical Gloves shelf life determination? EU Medical Device Regulations 1
A Test requirements for marketing in US when RATED values are not of US IEC 60601 - Medical Electrical Equipment Safety Standards Series 5
H Secondary Circuits, Voltage Test and Clearance/Creepage IEC 60601 - Medical Electrical Equipment Safety Standards Series 0
S Fogging test as per DIN 75201(50ug/g ) VDA Standards - Germany's Automotive Standards 3
R HV Test of HF Surgical Unit IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
R IEC 60601-1 - 11.1.3 e) Test criteria - Temperature Measurements IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
E 60950-1 resistance to abnormal heat test Various Other Specifications, Standards, and related Requirements 0

Similar threads

Top Bottom