The Anthropocene
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Engine Components and Filters: Damage Profiles, Probable Causes and Prevention
ENGINE COMPONENTS AND FILTERS: DAMAGE PROFILES, PROBABLE CAUSES AND PREVENTION Technical Information AFTERMARKET Contents 1 Introduction 5 2 General topics 6 2.1 Engine wear caused by contamination 6 2.2 Fuel flooding 8 2.3 Hydraulic lock 10 2.4 Increased oil consumption 12 3 Top of the piston and piston ring belt 14 3.1 Hole burned through the top of the piston in gasoline and diesel engines 14 3.2 Melting at the top of the piston and the top land of a gasoline engine 16 3.3 Melting at the top of the piston and the top land of a diesel engine 18 3.4 Broken piston ring lands 20 3.5 Valve impacts at the top of the piston and piston hammering at the cylinder head 22 3.6 Cracks in the top of the piston 24 4 Piston skirt 26 4.1 Piston seizure on the thrust and opposite side (piston skirt area only) 26 4.2 Piston seizure on one side of the piston skirt 27 4.3 Diagonal piston seizure next to the pin bore 28 4.4 Asymmetrical wear pattern on the piston skirt 30 4.5 Piston seizure in the lower piston skirt area only 31 4.6 Heavy wear at the piston skirt with a rough, matte surface 32 4.7 Wear marks on one side of the piston skirt 33 5 Support – piston pin bushing 34 5.1 Seizure in the pin bore 34 5.2 Cratered piston wall in the pin boss area 35 6 Piston rings 36 6.1 Piston rings with burn marks and seizure marks on the 36 piston skirt 6.2 Damage to the ring belt due to fractured piston rings 37 6.3 Heavy wear of the piston ring grooves and piston rings 38 6.4 Heavy radial wear of the piston rings 39 7 Cylinder liners 40 7.1 Pitting on the outer -
The Evolution of Diesel Engines
GENERAL ARTICLE The Evolution of Diesel Engines U Shrinivasa Rudolf Diesel thought of an engine which is inherently more efficient than the steam engines of the end-nineteenth century, for providing motive power in a distributed way. His intense perseverance, spread over a decade, led to the engines of today which bear his name. U Shrinivasa teaches Steam Engines: History vibrations and dynamics of machinery at the Department The origin of diesel engines is intimately related to the history of of Mechanical Engineering, steam engines. The Greeks and the Romans knew that steam IISc. His other interests include the use of straight could somehow be harnessed to do useful work. The device vegetable oils in diesel aeolipile (Figure 1) known to Hero of Alexandria was a primitive engines for sustainable reaction turbine apparently used to open temple doors! However development and working this aspect of obtaining power from steam was soon forgotten and with CAE applications in the industries. millennia later when there was a requirement for lifting water from coal mines, steam was introduced into a large vessel and quenched to create a low pressure for sucking the water to be pumped. Newcomen in 1710 introduced a cylinder piston ar- rangement and a hinged beam (Figure 2) such that water could be pumped from greater depths. The condensing steam in the cylin- der pulled the piston down to create the pumping action. Another half a century later, in 1765, James Watt avoided the cooling of the hot chamber containing steam by adding a separate condensing chamber (Figure 3). This successful steam engine pump found investors to manufacture it but the coal mines already had horses to lift the water to be pumped. -
MACHINES OR ENGINES, in GENERAL OR of POSITIVE-DISPLACEMENT TYPE, Eg STEAM ENGINES
F01B MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES (of rotary-piston or oscillating-piston type F01C; of non-positive-displacement type F01D; internal-combustion aspects of reciprocating-piston engines F02B57/00, F02B59/00; crankshafts, crossheads, connecting-rods F16C; flywheels F16F; gearings for interconverting rotary motion and reciprocating motion in general F16H; pistons, piston rods, cylinders, for engines in general F16J) Definition statement This subclass/group covers: Machines or engines, in general or of positive-displacement type References relevant to classification in this subclass This subclass/group does not cover: Rotary-piston or oscillating-piston F01C type Non-positive-displacement type F01D Informative references Attention is drawn to the following places, which may be of interest for search: Internal combustion engines F02B Internal combustion aspects of F02B 57/00; F02B 59/00 reciprocating piston engines Crankshafts, crossheads, F16C connecting-rods Flywheels F16F Gearings for interconverting rotary F16H motion and reciprocating motion in general Pistons, piston rods, cylinders for F16J engines in general 1 Cyclically operating valves for F01L machines or engines Lubrication of machines or engines in F01M general Steam engine plants F01K Glossary of terms In this subclass/group, the following terms (or expressions) are used with the meaning indicated: In patent documents the following abbreviations are often used: Engine a device for continuously converting fluid energy into mechanical power, Thus, this term includes, for example, steam piston engines or steam turbines, per se, or internal-combustion piston engines, but it excludes single-stroke devices. Machine a device which could equally be an engine and a pump, and not a device which is restricted to an engine or one which is restricted to a pump. -
Building a Small Horizontal Steam Engine
Building a Small Horizontal Steam Engine The front cylinder head is a pipe cap, THE small engine described in this the exterior of which is turned to pre- article was built by the writer in sent a more pleasing appearance, and his spare time—about an hour a day for drilled and threaded to receive the stuff- four months—and drives the machinery ing box, Fig. 2. The distance between in a small shop. At 40-lb. gauge pres- the edge of the front-end steam port and sure, the engine runs at 150 r.p.m., under the inner side of the cap, when screwed full load, and delivers a little over .4 home, should be much less than that brake horsepower. A cast steam chest, shown, not over ¼ in., for efficiency, and with larger and more direct steam ports, the same at the rear end. When the to reduce condensation losses; less clear- cap has been permanently screwed on ance in the cylinder ends, and larger the cylinder, one side is flattened, as bearing surfaces in several places, would shown, on the shaper or grinder, and the bring the efficiency of the engine up to a steam ports laid out and drilled. It would much higher point than this. In the be a decided advantage to make these writer's case, however, the engine is de- ports as much larger than given as is livering ample power for the purpose to possible, as the efficiency with ½-in. ports which it is applied, and consequently is far below what it might be. -
Overview of Materials Used for the Basic Elements of Hydraulic Actuators and Sealing Systems and Their Surfaces Modification Methods
materials Review Overview of Materials Used for the Basic Elements of Hydraulic Actuators and Sealing Systems and Their Surfaces Modification Methods Justyna Skowro ´nska* , Andrzej Kosucki and Łukasz Stawi ´nski Institute of Machine Tools and Production Engineering, Lodz University of Technology, ul. Stefanowskiego 1/15, 90-924 Lodz, Poland; [email protected] (A.K.); [email protected] (Ł.S.) * Correspondence: [email protected] Abstract: The article is an overview of various materials used in power hydraulics for basic hydraulic actuators components such as cylinders, cylinder caps, pistons, piston rods, glands, and sealing systems. The aim of this review is to systematize the state of the art in the field of materials and surface modification methods used in the production of actuators. The paper discusses the requirements for the elements of actuators and analyzes the existing literature in terms of appearing failures and damages. The most frequently applied materials used in power hydraulics are described, and various surface modifications of the discussed elements, which are aimed at improving the operating parameters of actuators, are presented. The most frequently used materials for actuators elements are iron alloys. However, due to rising ecological requirements, there is a tendency to looking for modern replacements to obtain the same or even better mechanical or tribological parameters. Sealing systems are manufactured mainly from thermoplastic or elastomeric polymers, which are characterized by Citation: Skowro´nska,J.; Kosucki, low friction and ensure the best possible interaction of seals with the cooperating element. In the A.; Stawi´nski,Ł. Overview of field of surface modification, among others, the issue of chromium plating of piston rods has been Materials Used for the Basic Elements discussed, which, due, to the toxicity of hexavalent chromium, should be replaced by other methods of Hydraulic Actuators and Sealing of improving surface properties. -
Steam As a General Purpose Technology: a Growth Accounting Perspective
Working Paper No. 75/03 Steam as a General Purpose Technology: A Growth Accounting Perspective Nicholas Crafts © Nicholas Crafts Department of Economic History London School of Economics May 2003 Department of Economic History London School of Economics Houghton Street London, WC2A 2AE Tel: +44 (0)20 7955 6399 Fax: +44 (0)20 7955 7730 1. Introduction* In recent years there has been an upsurge of interest among growth economists in General Purpose Technologies (GPTs). A GPT can be defined as "a technology that initially has much scope for improvement and evntually comes to be widely used, to have many uses, and to have many Hicksian and technological complementarities" (Lipsey et al., 1998a, p. 43). Electricity, steam and information and communications technologies (ICT) are generally regarded as being among the most important examples. An interesting aspect of the occasional arrival of new GPTs that dominate macroeconomic outcomes is that they imply that the growth process may be subject to episodes of sharp acceleration and deceleration. The initial impact of a GPT on overall productivity growth is typically minimal and the realization of its eventual potential may take several decades such that the largest growth effects are quite long- delayed, as with electricity in the early twentieth century (David, 1991). Subsequently, as the scope of the technology is finally exhausted, its impact on growth will fade away. If, at that point, a new GPT is yet to be discovered or only in its infancy, a growth slowdown might be observed. A good example of this is taken by the GPT literature to be the hiatus between steam and electricity in the later nineteenth century (Lipsey et al., 1998b), echoing the famous hypothesis first advanced by Phelps-Brown and Handfield-Jones, 1952) to explain the climacteric in British economic growth. -
Steam and You! How Steam Engines Helped the United States to Expand Reading
Name____________________________________ Date ____________ Steam and You! How Steam Engines Helped The United States To Expand Reading How Is Steam Used To Help People? (Please fill in any blank spaces as you read) Have you ever observed steam, also known as water vapor? For centuries, people have observed steam and how it moves. Describe steam on the line below. Does it rise or fall?____________________________________________________________ Steam is _______ and it ___________. When lots of steam moves into a pipe, it creates pressure that can be used to move things. Inventors discovered about 300 years ago that they could use steam to power machines. These machines have transformed human life. Steam is used today to help power ships and to spin large turbines that generate electricity for millions of people throughout the world. The steam engine was one of the most important inventions of the Industrial Revolution that occurred about from about 1760 to 1840. The Industrial Revolution was a time when machine technology rapidly changed society. Steam engines were used to power train locomotives, steamboats, machines in factories, equipment in mines, and even automobiles before other kinds of engines were invented. Boiling water in a tea kettle produces A steamboat uses a steam engine to steam. Steam can power a steam engine. turn a paddlewheel to move the boat. A steam locomotive was powered when A steam turbine is a large metal cylinder coal or wood was burned inside it to boil with large fan blades that can spin when water to make steam. The steam steam flows through its blades. -
Swampʼs Diesel Performance Tips to Help Remove and Install Power
Injectors-Chips-Clutches-Transmissions-Turbos-Engines-Fuel Systems Swampʼs Diesel Performance Competition Parts For Your Diesel 304-A Sand Hill Rd. La Vergne, TN 37086 Tel 615-793-5573 or (866) 595-8724/ Fax 615-793-5572 Email: [email protected] Tips to help remove and install Power Stroke injectors. Removal: After removing the valve covers and the valve cover gaskets, but before removing any injectors, drain the oil rails by removing the drain plugs inside the valve cover. On 94-97 trucks theyʼre just under where the electrical connectors are on the gasket. These plugs are very tight; give them a sharp blow with a hammer and punch to help break them loose, then use a 1/8" Allen wrench. The oil will drain out into the valve train area and from there into the crankcase. Donʼt drop the plugs down the push rod holes! Also remove one of the plugs on top of each oil rail, (beside where the lines from the High Pressure Oil Pump enter) for a vent to allow air to enter so the oil can drain. The plugs are 5/8”. Inspect the plug O-rings and replace if necessary. If the plugs under the covers leak, it will cause a substantial loss of performance. When removing the injectors, oil and fuel from the passages in the cylinder head drains down through the injector bore into the cylinders. If not removed, this can hydro-lock the engine when cranking. There is a ~40cc dish in the center of each piston. Fluid accumulates in it, as well as in the corner on the outside of the piston between the piston top and the cylinder wall, due to the 45* slope of the cylinder bank. -
Steam Engine Use and Development
STEAM ENGINE USE AND DEVELOPMENT A diagram of Cameron's aero-steam engine, from an 1876 dictionary The first industrial applications of the vacuum engines were in the pumping of water from deep mineshafts. The Newcomen steam engine [[12]] operated by admitting steam to the operating chamber, closing the valve, and then admitting a spray of cold water. The water vapor condenses to a much smaller volume of water, creating a vacuum in the chamber. Atmospheric pressure, operating on the opposite side of a piston, pushes the piston to the bottom of the chamber. In mineshaft pumps, the piston was connected to an operating rod that descended the shaft to a pump chamber. The oscillations of the operating rod are transferred to a pump piston that moves the water, through check valves, to the top of the shaft. The first significant improvement, 60 years later, was creation of a separate condensing chamber with a valve between the operating chamber and the condensing chamber. This improvement was invented on Glasgow Green, Scotland by James Watt[[13]] and subsequently developed by him in Birmingham, England, to produce the Watt steam engine [[14]] with greatly increased efficiency. The next improvement was the replacement of manually operated valves with valves operated by the engine itself. In 1802 William Symington built the "first practical steamboat", and in 1807 Robert Fulton used the Watt steam engine to power the first commercially successful steamboat. Such early vacuum, or condensing, engines are severely limited in their efficiency but are relatively safe since the steam is at very low pressure and structural failure of the engine will be by inward collapse rather than an outward explosion. -
Meet the Gilded Lady 2 Mummies Now Open
Member Magazine Spring 2017 Vol. 42 No. 2 Mummies meet the gilded lady 2 mummies now open Seeing Inside Today, computerized inside of mummies, revealing CT scans of the Gilded Lady tomography (CT) scanning details about the person’s reveal that she was probably offers researchers glimpses age, appearance, and health. in her forties. They also suggest of mummified individuals “Scans like these are noninvasive, that she may have suffered like never before. By combining they’re repeatable, and they from tuberculosis, a common thousands of cross-sectioned can be done without damaging disease at the time. x-ray images, CT scans let the history that we’re trying researchers examine the to understand,” Thomas says. Mummy #30007, known as the Gilded Lady, is one of the most beautifully preserved mummies from The Field Museum’s collection, and one of 19 now on view in the special exhibition Mummies. For decades, keeping mummies like this one well preserved also meant severely limiting the ability of researchers to study them. The result is that little was known about the Gilded Lady beyond what could be gleaned from the mummy’s exterior, with its intricate linen bindings, gilded headdress, and painted facial features. Exterior details do offer some clues. The mummy dates from 30 BC–AD 395, a period when Egypt was a province of the Roman Empire. While the practice of mummification endured in Egypt, it was being transformed by Roman influences. Before the Roman era, for example, mummies had been placed in wooden coffins, while the Gilded Lady is preserved in only linen wrappings and cartonnage, a papier mâché-like material. -
Development of Predictive Gasoline Direct Fuel Injector Model for Improved
Development of Predictive Gasoline Direct Fuel Injector Model for Improved In-cylinder Combustion Characterization Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Mohit Atul Mandokhot Graduate Program in Mechanical Engineering The Ohio State University 2018 Thesis Committee Prof. Shawn Midlam-Mohler, Advisor Prof. Giorgio Rizzoni 1 Copyrighted by Mohit Atul Mandokhot 2018 2 Abstract Gasoline direct fuel injection systems have gained importance due to the increasing level of emissions regulation on SI combustion systems. Direct fuel injection delivery to cylinder provides better atomization and fuel mixing performance, enabling homogenous mixture and better in-cylinder combustion. Increasing focus over the last few decades has been on better characterization of such gasoline direct fuel injection systems. Solenoid powered injectors act as actuators and enable accurate fuel delivery into the cylinder for a combustion event. Characterization of injector’s fuel delivery performance is an important aspect of achieving improved in-cylinder combustion performance. The objective of the current thesis is to develop a numerical physics based fuel injector model that provides a reliable prediction of flow rate and needle lift, in order to be used to improve in-cylinder combustion performance using 3D CFD model methodology. The developed model provides a reliable estimate of flow rate of developed injector, which is experimentally verified against instantaneous flow rate data provided by typical suppliers. In cases where inadequate prediction performance was noted, the errors arise out of lack of high fidelity electromagnetic modeling data, damping characteristics inside model and lack of geometry data to capture performance of highest accuracy. -
Place Names Describing Fossils in Oral Traditions
Place names describing fossils in oral traditions ADRIENNE MAYOR Classics Department, Stanford University, Stanford CA 94305 (e-mail: [email protected]) Abstract: Folk explanations of notable geological features, including fossils, are found around the world. Observations of fossil exposures (bones, footprints, etc.) led to place names for rivers, mountains, valleys, mounds, caves, springs, tracks, and other geological and palaeonto- logical sites. Some names describe prehistoric remains and/or refer to traditional interpretations of fossils. This paper presents case studies of fossil-related place names in ancient and modern Europe and China, and Native American examples in Canada, the United States, and Mexico. Evidence for the earliest known fossil-related place names comes from ancient Greco-Roman and Chinese literature. The earliest documented fossil-related place name in the New World was preserved in a written text by the Spanish in the sixteenth century. In many instances, fossil geonames are purely descriptive; in others, however, the mythology about a specific fossil locality survives along with the name; in still other cases the geomythology is suggested by recorded traditions about similar palaeontological phenomena. The antiquity and continuity of some fossil-related place names shows that people had observed and speculated about miner- alized traces of extinct life forms long before modern scientific investigations. Traditional place names can reveal heretofore unknown geomyths as well as new geologically-important sites. Traditional folk names for geological features in the Named fossil sites in classical antiquity landscape commonly refer to mythological or and modern Greece legendary stories that accounted for them (Vitaliano 1973). Landmarks notable for conspicuous fossils Evidence for the practice of naming specific fossil have been named descriptively or mythologically locales can be found in classical antiquity.