BOOK REVIEW. FUNDAMENTALS OF MACHINING AND MACHINE TOOLS by. Goeffrey Boothroyd and Winston A Knight. Marcel Dekker, lnc., New York. Fundamentals ofMachining and Machine Tools (2nd edition). By GEOFFREY BOOTHROYD and. W. A. KNIGHT (Marcel Dekker, Inc., )[Pp. Trove: Find and get Australian resources. Books, images, historic newspapers, maps, archives and more.
|Language:||English, Spanish, French|
|Genre:||Health & Fitness|
|ePub File Size:||30.53 MB|
|PDF File Size:||17.74 MB|
|Distribution:||Free* [*Sign up for free]|
Download Fundamentals of Metal Machining and Machine Tools By Winston A. Knight, Geoffrey Boothroyd – In the more than 15 years since the second edition . Fundamentals of Machining and Machine Tools Second Edition Geoffrey Boothroyd Winston A. Knight University of Rhode Island Kingston, Rhode Island. i Fundamentals of Machining and Machine Tools Second Edition Geoffrey Boothroyd Winston A. Knight University of Rhode Island Kingston, Rhode Island ISBN.
Ease of Use Overcoming historical shortcomings[ edit ] Over time, the historical shortcomings of CAM are being attenuated, both by providers of niche solutions and by providers of high-end solutions. This is occurring primarily in three arenas: Ease of usage Integration with PLM and the extended enterprise  Ease in use For the user who is just getting started as a CAM user, out-of-the-box capabilities providing Process Wizards, templates, libraries, machine tool kits, automated feature based machining and job function specific tailorable user interfaces build user confidence and speed the learning curve. User confidence is further built on 3D visualization through a closer integration with the 3D CAD environment, including error-avoiding simulations and optimizations. Manufacturing complexity The manufacturing environment is increasingly complex. The need for CAM and PLM tools by the manufacturing engineer, NC programmer or machinist is similar to the need for computer assistance by the pilot of modern aircraft systems. The modern machinery cannot be properly used without this assistance.
Industry Series. Issued November Lathe is considered as one of the oldest machine tools and is widely used in industries. The process of machining a workpiece to the required shape and size by moving the cutting tool either The metal burrs resulting from turning operation.
Fundamentals of Metal Machining and Machine Tools download free everybk. It shows the wide range of chip flows that are free to be. Jump to: navigation, search. New Guinea in Mobile machine shop truck of the US Army with machinists working on automotive parts.
Machining is any of various processes in which a piece of raw material is cut into a desired final Milling operations are operations in which the cutting tool rotates to bring. Stephenson, John S. Manufacturing Technology, Vol. Topics include: operations, mechanics of cutting, temperature, tool life. Because war with the French was imminent, it was not possible to obtain additional supplies from Europe.
Eli Whitney, now recognized as one of the pioneers of mass production, offered to contract to make 10, muskets in 28 months.
At first, Whitney designed templates for each part, but he could not find machinists capable of following the contours. Next, he developed a milling machine that could follow the templates, but hand-fitting of the parts was still necessary.
Eventually, the factory at New Haven, CT, built especially for the manufacture of the muskets, added machines for producing interchangeable parts. These machines reduced the skills required by the various workers and allowed significant increases in the rate of production. In an historic demonstration in , Whitney surprised his distinguished visitors when he assembled a musket lock after selecting a set of parts from a random heap.
First, parts were manufactured on machines, resulting in consistently higher quality than that of handmade parts. These parts were interchangeable and, as a consequence, assembly work was simplified. Second, the accuracy of the final product could be maintained at a higher standard. Third, production rates could be significantly increased.
These concepts became known as the American system of manufacture. In , Evans used three types of conveyors in an automatic flour mill that required only two operators.
The first operator poured grain into a hopper, Introduction 3 and the second filled sacks with the flour produced by the mill. All the intermediate operations were carried out automatically, with conveyors carrying the material from operation to operation.
A significant contribution to the development of assembly methods was made by Elihu Root. In , Root joined the company that was producing Colt sixshooters.
Even though, at that time, the various operations of assembling the component parts were quite simple, he divided these operations into basic units that could be completed more quickly and with less chance of error.
Frederick Winslow Taylor was probably the first person to introduce the methods of time and motion study to manufacturing technology. Taylor also discovered that any worker has an optimum speed of working that, if exceeded, results in a reduction in overall performance.
Undoubtedly, the principal contributor to the development of modern production and assembly methods was Henry Ford. He described his principles of assembly in the following words: Place the tools and then the men in the sequence of the operations so that each part shall travel the least distance while in the process of finishing. Use work slides or some other form of carrier so that when a workman completes his operation he drops the part always in the same place which must always be the most convenient place to his hand — and if possible, have gravity carry the part to the next workman.
Use sliding assembly lines by which parts to be assembled are delivered at convenient intervals, spaced to make it easier to work on them. These principles were gradually applied in the production of the Model T Ford automobile. The modern assembly-line technique was first employed in the assembly of a flywheel magneto. In the original method, one operator assembled a magneto in 20 min. It was found that when the process was divided into 29 individual operations carried out by different workers situated at assembly stations spaced along an assembly line, the total assembly time was reduced to 13 min 10 sec.
When the height of the assembly line was raised by 8 in. This result encouraged Henry Ford to utilize his system of assembly in other departments of the factory, which were producing subassemblies for the car. Subsequently, this brought a continuous and rapidly increasing flow of 4 Assembly Automation and Product Design subassemblies to those working on the main car assembly.
It was found that these workers could not cope with the increased load, and it soon became clear that the main assembly would also have to be carried out on an assembly line. At first, the movement of the main assemblies was achieved simply by pulling them by a rope from station to station. However, even this development produced an amazing reduction in the total time of assembly from 12 hr 28 min to 5 hr 50 min.
Eventually, a power-driven endless conveyor was installed; it was flush with the floor and wide enough to accommodate a chassis. With the introduction of this conveyor, the total assembly time was reduced to 93 min.
Further improvements led to an even shorter overall assembly time and, eventually, a production rate of 1 car every 10 sec of the working day was achieved. Eventually, Ford adopted a method of isolating difficulties and correcting them in advance before actual mass production began. The method was basically to set up a pilot plant where a complete assembly line was installed in which were used the same tools, templates, forming devices, gauges, and even the same labor skills that would eventually be used for mass production.
This method has now become the standard practice for all large assembly plants. The type of assembly system described in the preceding text is usually referred to as a manual assembly line, and it is still the most common method of assembling mass- or large-batch-produced products. Since the beginning of the 20th century, however, methods of replacing manual assembly workers by mechanical devices have been introduced.
These devices take the form of automatic assembly devices or workheads with part-feeding mechanisms and, more recently, robots with part trays.
Thus, in the beginning, automated screwdrivers, nut runners, riveters, spotwelding heads, and pick-and-place mechanisms were positioned on transfer devices that moved the assemblies from station to station.
Each workhead was supplied with oriented parts either from a magazine or from an automatic feeding and orienting device, usually a vibratory-bowl feeder. The special single-purpose workheads could continually repeat the same operation, usually taking no more than a few seconds. For two-shift working, this translates into an annual production volume of several million. Automation of this type was usually referred to as mechanization and because it could be applied only in mass production, its development was closely tied to certain industries such as those manufacturing armaments, automobiles, watches and clocks, and other consumer products.
Mechanization was used in the manufacture of individual items such as light bulbs and safety pins that are produced in large quantities. However, it was probably in process manufacturing, such as Introduction 5 that found in the food, drug, and cosmetic industries, that mechanization was first applied on a large scale.
As a result, since World War II, increasing attention has been given to the possibility of using robots in assembly work.
According to Schwartz , George Devol, Jr. The first modern industrial robot, the Unimate  was conceived in at a meeting between inventors George Devol and Joseph Engelberger. In the Unimate joined the assembly line at General Motors handling die castings. The first uses of industrial robots were in materials handling such as diecasting and punch-press operations, and by they started to be used in assembly.
By , more than 30 different robots were available from 15 manufacturers. In spite of these developments, mechanical and electromechanical assemblies remain difficult to automate except in mass-production quantities. The exception to this is the electronics industry, more specifically, the printed-circuit-board PCB assembly.
Because of the special nature of this product, introduced in the early s, it has been found possible to apply assembly automation even in small-batch production.
At first, PCB components were hand-inserted and their leads hand-soldered. To reduce the soldering time, wave-soldering was developed in which all the leads are soldered in one pass of the board through the soldering machine. The next step was automatic insertion of the component leads. Although initially most small components were axial-lead components, several large electronics manufacturers developed multiple-lead insertion systems.
The PCB is an ideal product for the application of assembly automation.
It is produced in vast quantities, albeit in a multitude of styles. Assembly of components is carried out in the same direction, and the components types are limited.
With the standardization of components now taking place, a high proportion of PCBs can be assembled entirely automatically. Also, the automatic-insertion machines are easy to program and set up and can perform one to two insertions per second. Consequently, relatively slow manual assembly is often economic for only very small batches.
With the present widespread engineering trend toward replacing mechanical control devices and mechanisms with electronics, PCB assembly automation is now finding broad application; indeed, one of the principal applications of assembly robots is the insertion of nonstandard odd-form electronic components that cannot be handled by the available automatic-insertion machines.
For a new product, the following considerations are generally important: 1. Suitability of the product design Production rate required Availability of labor Market life of the product If the product has not been designed with automatic assembly in mind, manual assembly is probably the only possibility. Similarly, automation will not be practical unless the anticipated production rate is high.
If labor is plentiful, the degree of automation desirable will depend on the anticipated reduction in the cost of assembly and the increase in production rate, assuming the increase can be absorbed by the market. The capital investment in automatic machinery must usually be amortized over the market life of the product.
Clearly, if the market life of the product is short, automation will be difficult to justify. A shortage of assembly workers will often lead a manufacturer to consider automatic assembly when manual assembly would be less expensive.
This situation frequently arises when a rapid increase in demand for a product occurs.