What Engineers Know And How They Know It Pdf Books' title='What Engineers Know And How They Know It Pdf Books' />Public Speaking for Engineers ASCEIf you are like many people, the thought of giving a speech to a group of strangers can strike terror into your heart. As an engineer, you know that employers put a premium on soft skills such as public speaking, but youre puzzled about how you can improve your own performance. Shoots Veis understands your predicament. A practicing engineer himself, he often makes presentations to councils, zoning boards, land use commissions, any of the municipal bodies that contract for infrastructure. He has been on the other side of the podium, too during a stint on the Billings, Montana, city council, he listened to a lot of engineers talk about projects. Hes seen the good, the bad, and the downright embarrassing. In Public Speaking for Engineers Communicating Effectively with Clients, the Public, and Local Government, Veis takes readers step by step through the process of preparing for a presentation. He breaks the main topicsspeech planning, design, and deliveryinto component pieces and explains the range of choices, emphasizing the importance of understanding your audience. ImageType-100/0211-1/{6815BF5A-C6E0-4DF1-B084-3A280538C0E9}Img100.jpg' alt='What Engineers Know And How They Know It Pdf Books' title='What Engineers Know And How They Know It Pdf Books' />Throughout the book, he uses an ongoing example to illustrate the path for planning, preparing, and delivering a speech. A dozen or so case studies offer tales of real life successes and missed opportunities. In the final chapter, Veis delves into what local governments do and how they do it. Veis offers a wealth of practical advice and enthusiastic coaching to anyone who needs to make a technical presentation to a nontechnical group of decision makers. Engineers of all kinds will appreciate this roadmap to a successful public presentation. Christopher A. Shoots Veis, P. E., is a senior project engineer focusing on municipal engineering assignments involving water and wastewater systems, land development, permitting, and project management. Electrical engineering is a professional engineering discipline that generally deals with the study and application of electricity, electronics, and electromagnetism. He served for five years as an elected member of the Billings, Montana, city council. What Engineers Know And How They Know It Pdf Books' title='What Engineers Know And How They Know It Pdf Books' />Tricks Engineers Need to Know About Fasteners Engineer. Dog. Youd expect an engineer to know everything about a basic subject like nuts and bolts right Well fasteners are one of those topics that seem simple at first but turn out to have much more depth than you expected. What follows are 1. UPDATED MARCH 2. 01. It has come to my attention that there is testing data available that makes the counter argument to my first point in this article. What Engineers Know And How They Know It Pdf Books' title='What Engineers Know And How They Know It Pdf Books' />In the interest of transparency and good scientific discussion, Ive provided links to all sources mentioned at the end of point 1. When faced with contradictory test results, if we assume the methodology and integrity of all sources are without fault, it is reasonable to conclude that your results may vary. Many factors could significantly affect testing results including variances from manufacturing process, fastener clamped materials, heat treating, surface finishes, ambient conditions, and bolt diameter. Split washers have been experimentally proven to be ineffective locking devices and can even aid self loosening over time. And yet I see these things in use everywhere, so what gives In theory split washers aka lock washers or helical spring washers are supposed to work by squishing flat between the nut and the mounting surface when you tighten them. At this point the sharp edges of the washer are supposed to dig into the nut and mounting surface to prevent counter clockwise rotation. In practice a split washer is unable to gain any purchase against hard surfaces and does not actually prevent rotation. The problem is that split washers make for poor springs and bottom out after only a small percentage on order of 1. The only time a split washer might prove useful would be for fastening onto soft easily deformed surfaces such as wood, where the washers springiness sharp edges could actually work. The evidence against split washers started stacking up in the 1. Gerhard Junker published some of his lab experiments. He invented a machine specifically for testing the effect of vibrations on threaded fasteners. The first thing he discovered was that transverse vibration loads generate a much greater loosening effect than do axial vibrations. Good to know. His second discovery was made by plotting the bolt tension vs vibration cycles to create a preload decay chart. When he compared the preload decay of a bolt split washer combo to bolt by its lonesome, he found that the split washer caused the connection to loosen sooner, as seen below. Not to worry, there are better locking options available. Chemical lockers like Loctite, deformed thread lock nuts, and Nyloc nuts should be your everyday go to locking devices. If you have some money to burn then wedge lock Nord lock washers Serrated flange nuts are probably the best way to go. When lives are on the line you may want to employ a positive locking device such as a castle nut or a slotted nut. No amount of vibration will break this kind of connection Since this one is sure to stir things up when you mention it the guys at the office, Ive provided my sources below. A Article 1 n boltscience. Article 2 on Boltscience. Article 3 on Boltscience. B pdf file from hillcountryengineering. D Awesome video showing actual testing and how preload decay charts are generated. Alternate Testing Video 1 making the counter argument in favor of split washers. Alternate Testing Video 2  making the counter argument in favor of split washers. What Engineers Know And How They Know It Pdf Books' title='What Engineers Know And How They Know It Pdf Books' />Turnkey Contract Conditions of Contract for EPCTurnkey ProjectsADDED APRIL 2013 FIDIC Guidance Memorandum to Users of the 1999 Conditions of Contract dated 1st. Preserving the Knowledge of the Ancients Ive found that most of the technical books published before about 1964 never had their copyrights renewed, so now are in. A Collection of Free C Programming Books. Financial Numerical Recipes in C Applications in Finance. This book provides a good deal of useful examples and. Iuvcr Serial. Youd expect an engineer to know everything about a basic subject like nuts and bolts right Well fasteners are one of those topics that seem simple at first but. How Safe Is Safe Enough Safe isnt a defined engineering term. Planners must decide, based on risks and probabilities, how safe they want to make. Double Nutted joints with jam nuts are affected by order of clamping. While Im talking about bolt locking techniques, Ill share another interesting one For double nut connections involving the use of a jam nut a standard nut, it REALLY matters what order you install them in. The jam nut should go on first Otherwise the effectiveness of the nut pair is greatly reduced. Double nut Source. Before I move on to the next one I need to clarify the difference between static loads and fatigue loads. Static loads do not change over time. If a bolt is rated to yield at 3,0. However, if you were to vary that applied load over time you can fatigue the bolt until it breaks using less than 3,0. In the same way that a small stream can carve out the Grand Canyon, fatigue loads gradually chip away at the structural integrity of fasteners over time. The relationship between fatigue load and the number of cycles until bolt failure occurs can be predicted using experimentation. It turns out that you can make reasonably accurate predictions of the cycle count at failure by performing as few as three experiments though I would recommend doing at least 6 to attain some real accuracy. All it takes are a few data points and a regression line to create a high cycle fatigue life curve aka an S N curve. We dont put the ultimate static loading on the graph, but if we did it would be the highest point on the applied load axis and the zero point on the cycles axis. Why is this useful Now that you know bolts can break from small fatigue loads, imagine trying to build a bridge using riveted or bolted connections. How could you trust that you ever had a big enough fastener It turns out that fatigue loads below a certain threshold will never cause the fastener to break. As a very general estimate, a bolt will require an infinite number of cycles to break if the fatigue load is around 3. You can expect the bolt to break in a few thousand cycles if the fatigue load is about 8. Note the exact percentage can vary dramatically based on material composition and ambient conditions. UPDATED For maximum strength tighten bolts up to the yield pointFor maximum durability, dont There is a common misunderstanding that a bolt within a securely fastened connection is impervious to outside forces if hey dont exceed the clamped load of the connection. That is, the myth says a bolt clamped to 5. This is not so In fact ANY additional load, no matter how small, will add to the tension in the bolt. But not at a 1 1 rate. Think of pulling on a fastened connection as if it were 2 stacked springs. Both springs stretch measurably, but the weaker one stretches more. Part of the external load is absorbed by the joint and part by the fastener. To be crystal clear, as you tighten the nut the bolt will compress the two parts together. The bolt itself has an internal reaction force equal to the amplitude of the compression force, but the bolt itself is in tension. If you were to graph the tension on the bolt while you tighten the nut, the plot would look like the graph below. To get the greatest clamping force out of the bolt we would to tighten it all the way up to the yield point. Any more force and the bolt will enter the plastic region and permanently deform. In practice engineers dont design that way. Since any additional force will begin to yield the bolt, you want to give yourself some margin for error. Engineers select a bolt tension that is somewhere between the calculable minimum functional clamping force and the yielding force. Sources Shingleys Standard Handbook  Article on Fastenal 5. It is actually quite difficult to determine the exact load the fastener sees during clamping. We now know how important it is to avoid over tightening a bolt, but how do we know when it is yielding   For everyday purposes the clamping force can be approximated by measuring the tightening torque.