Engineering Stack Exchange
Engineering Stack Exchange

Questions tagged [quality-engineering]

21 questions
13
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4 answers

In aluminum machining, what are the most common factors that might cause a machined component to have warping issues?

I am currently having an issue where features of my machined parts are warping. I am using Alloy 7050 Type I and Type III in this particular case. Using a feeler gauge and a certified, calibrated granite slab, I am getting out-of-flatness…
Tim D
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7
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5 answers

How to identify low quality electronic components early?

Our component sourcing organization purchases large amount of electronic components from suppliers. I believe this is through a bid process. Engineering provides the sourcing organization specification, and they purchase these parts for the plant to…
user1586
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6
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3 answers

How can the vendor be approved/disapproved based on validation test data?

The power requirement for a sub system is 5V +/- 10% @ 1A of current. A RFQ was issued and a prospect vendor was selected. A first article of inspection (FAIR) has been submitted which includes 15 power supply samples. The samples have been tested…
Mahendra Gunawardena
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4
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2 answers

How can I better structure documentation for a quality control process?

In my organization, every unit is built by hand, and every unit is tested. Every product has a written construction procedure and a written test procedure. We're in the process of updating and improving all those procedures. One potential problem…
Stephen Collings
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4
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How do products like the overheating Snapdragon CPU make it through quality control?

Almost all of the new Snapdragon CPU series (610, 810) have an overheating problem. This overheating problem may occur in the first few hours of using mobile phones that are equipped with the CPU, as we can see from the various reviews from around…
imin
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3
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3 answers

Guidelines to develop quality engineering training content and select a trainer

Our organization has recognized the need to improve quality of both incoming material and outgoing products. Our products are primarily electrical/electronic but mechanical components are an integral part of the end product. As result of sharing…
user1586
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3
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3 answers

Rule of Tens/Ten to 1 Rule in Measurement and Inspection

I'm trying to clarify my understanding about the requirements [read: best practices] for measurement resolution and measurement confidence. The "Rule of 10s" is a commonly tossed around guideline for measurement resolution that, to the best of my…
Argonax
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How do I update an individual control chart?

I'm finding myself using control charts and I'm unclear on a very basic point. I've read page after page of texts, but they all focus on how to make the initial chart rather than walking you through how to update it. To make things easier, I'll set…
Broklynite
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2
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1 answer

Document Naming System

This is actually only tangent to engineering, and mostly related to Quality Management Systems, so this could be off topic. For a document which has a specific Document Naming System in a Document Control format such as: [Project Name]-[Document…
Brethlosze
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How do I find a target standard deviation for my own testing given a confidence level, a mean, and bounds for the interval?

I'm working on a project involving a couple of material dispensers, and the customer we're designing them for has asked us to keep the output of the dispensers within a set range 95% of the time. I'm struggling with the statistics aspect of tuning…
Grumpy
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How can I calculate uncertainty based on measurements from multiple separate runs?

I am using standard test blocks to find the uncertainty of a supermicrometer, which is capable of measuring down to 1/10 of a micron. The issue is that it measures the EXACT same length within a run of even 100 measurements. Understandably, it is…
Gevorg Ter-Isahakyan
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Are 3d printed gears (ABS) suitable for long term use?

i want to print a worm gear for a robot. This robot will work every day for at least 10 hours. The gears size is about the half of a sheet paper. I searched the internet for example in industrial use. I can not find much about the life span of 3d…
user14157
1
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0 answers

Detergency and dispersancy

Abstract:The detergency property in oil comes from a chemical additive called detergent which has a property of preventing the deposition of carbon deposits and wash it away. There is also this property of lube oil being Dispersant where an additive…
Shakespeare
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1 answer

Is it possible to conduct a completely random Quality Test?

I work in the aerospace industry and would like to utilize simple, mass market COTS assemblies as critical components. Let's assume it's a simple solenoid valve. Rather than create a contract or determine all of the criteria the seller qualifies…
Jee
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How to determine the effect of manufacturing variability on assembly of items

Any help is appreciated. Below are some details The product has around 20 different components (including ones manufactured to spec, fasteners, off the shelf, consumables, etc.) Lets assume the production volume would be 500 units/year. I need…
Karthik
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