Tag Archives: failure

Failure is not always a bad thing. Sometimes it’s exactly what you want. You might start with one component that’s been well tested with the existing system. It can be a simple clamp or a complicated swing valve (like the one pictured from DHV Industries). You probably tested it out when it was originally implemented and proved you had plenty of safety margin. But now your system has changed. Maybe you’re sending your system into freezing winter temperatures or hot, arid deserts. Maybe you’ve got a more powerful compressor that generates much higher pressures than you’d been dealing with before. So how do you test that component? Most standards would suggest you take your max operating conditions and increase the magnitude by 50% and test at those conditions. That proof test would verify your equipment can operate safely at your max conditions giving you a 1.5 safety margin. But in…

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I have become the bane of my kids’ teachers existence.  They go running when they see me. Part of the reason is because I think school isn’t demanding enough.  I’m sure they view me as one of those parents who thinks SO highly of their child and wants them to be in advanced everything.  Maybe there’s a bit of truth to that, but I have an even more serious reason: I want them to be challenged. The other day while talking to several fellow engineers on Twitter, the discussion turned to failing courses.  It turned out that a lot of us had actually failed courses at some point during our career.  Yet all of us had gone on to become engineers.  Chris made the point that failing teaches us something.  While I think it would be better to be given the tools to prevent failure, he is right: failure can…

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Making mistakes is easy, I do them all the time! However, what we do about them is more important. In this week’s theme of “mistakes,” I can easy spend time telling you about the mess I have gotten into and how I should have been more careful, but there’s nothing I can do about them. So I want to talk about keeping face after making mistakes. We all know that moment when your heart sinks, your skin turns cold and you start to sweat. Your first reaction is “Oh God What Have I Done!” and then you start to pray no one else has seen your massive mistake and your hoping you can run away and hide – no one will notice will they? It’s not your fault, it has to be someone else who fed you wrong information! Or some faulty device or the fault of the technician –…

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As a mechanical engineer I tend to focus mostly on the mechanisms that actually do the work. Sometimes it’s easy to forget about the components that take the work. I’m talking about bearings. They’re so essential for many things with moving systems, from everything to your car to a simple valve. The purpose of a bearing is to allow relative motion with a minimum amount of friction. On that end, the material for the bearing can become an incredibly crucial point. For high stress applications it needs to have good tensile and fatigue strength. But in order to absorb energy and not damage surrounding components you also might want it to be soft and with a low melting point. If you’re dealing in the aerospace industry you can bring in a third complication: weight. Bearings can be anything from a simple roller ball style to a flat plate bearing. Plates can…

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This week’s theme at Engineer Blogs asks the authors to recount their path to “success”. What were the turning points? Who was involved? And so forth. The arc of a storyline usually tells of a protagonist that is transformed as the events unfold from beginning to end. Tiger Woods is a good example — rising prodigy, international superstar, fall from grace. Adolf Hitler is another great example — struggling artist, dictator extraordinaire, suicide. Or we can look at Barack Obama — fatherless childhood, President of the United States, Kenyan Muslim Marxist. But not everyone is blessed enough to have a sweeping story arc in their lives. Donald Trump, for example, is more of a sine wave than an arc. And for me, it’s more or less a straight line with a shallow slope. A suburban upbringing. Good at math and physics in high school. Studied engineering. Works in engineering. Continues…

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When a major hardware component goes it can often fail in catastrophic and spectacular ways. If your serpentine belt in your engine breaks not only does it mean your crankshaft stops but then by extension your alternator will stop charging your batteries which could result in power loss pretty quickly. Then your water pump would stop and your engine would start overheating while  simultaneously your power steering pump would quit meaning you’d feel like you went from driving a modern car to some sort of fifty year old tractor. Serpentine belts are treaded on the inside for this reason. Wear can be measured much like on your tires where the depth of the tread tells you how long you have left to go on it and you can also visually inspect for cracks. But in more complicated assemblies, a single point of failure isn’t always as obvious. The result can be catastrophic system…

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