A Course of Instruction in Elementary Machine Design: Arranged for Students of the Junior Class, Purdue University, Lafayette, Ind |
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A Course of Instruction in Elementary Machine Design, Arranged for Use in ... James David Hoffman No preview available - 2017 |
A Course of Instruction in Elementary Machine Design: Arranged for Students ... James David Hoffman No preview available - 2016 |
A Course of Instruction in Elementary Machine Design: Arranged for Students ... J. D. Hoffman No preview available - 2017 |
Common terms and phrases
angle applied assume Babbitt Metal beam belt bending block boiler bolt boxes calculated cap screw cast iron cent coefficient of friction Collars compression Copper COUPLING cylinder Diam diameter Drill f₁ factor of safety fastening feet fibre stress flange Fly Wheel Foot force formula friction wheels gives HANGER hole Horse Power Inches Inches Inches increases joint journal KINEMATIC SHEET length load Machine Design malleable manganese material maximum metal mild steel modulus obtained pig iron pitch plate pounds per square pressure pulley pulley rim punch Purdue University radius rectangular req'd resist rope screw thread shape shear shell shown in Fig silicon sizes sliding head solid spur gear square inch standard T₁ T₂ taken tensile strength thickness thread thrust bearing toggle tooth twisting ultimate strength varies velocity W₁ weight width worm wrought iron
Popular passages
Page 79 - ... pounds per square inch, which corresponds to a factor of safety of 12. The shape of the section may be varied to suit the conditions, from a large and thin section as here treated, to a small compact and possibly solid section. The latter condition prevails in some machines where the gap is long and the main section would be necessarily crowded into the smallest space.
Page 39 - In such wheels the bending due to centrifugal force is slight, and may safely be disregarded. 2. Rim joints midway between the arms are a serious defect and reduce the factor of safety very materially. Such joints are as serious mistakes in design as would be a joint in the middle of a girder under a heavy load. 3. Joints made in the ordinary manner, with internal flanges and bolts, are probably the worst that could be devised for this purpose. Under the most favorable circumstances they have only...
Page 91 - First, the lever /' here becomes so small that a separate crank can not be used and an eccentric is substituted, the length of the lever /' being the distance between the centre of the shaft and the centre of the eccentric. Second, the thrust of the sliding block is received through a screw directly against the base of. the frame. A hollow rectangular section is suggested as the best shape of the frame. W = I — Г = в = THIRD ALTERNATE, DESIGN NO. 1. 187. Assignment:— W— (Not over 100») /=...
Page 39 - ... proportions usual among engine builders, and having the usual number of arms, have a sufficient factor of safety at a rim speed of 100 feet per second, if the iron is of good quality and there are no serious cooling strains. In such wheels the bending due to centrifugal force is slight and may be safely disregarded.
Page 11 - Factor of Safety: — The factor of safety is the ratio of the ultimate stress to the working stress.
Page 14 - ... the square of the least radius of gyration and qa coefficient depending upon the condition of the ends of the column (whether fixed or free) and upon the material.
Page 39 - The following general conclusions seem justified by these tests. 1. Fly-wheels with solid rims, of the proportions usual among engine builders and having the usual number of arms, have a sufficient factor of safety at a rim speed of 100 feet per second if the iron is of good quality and there are no serious cooling strains. In such wheels the bending due to centrifugal force is slight, and may safely be disregarded.
Page 75 - This seems to agree very well with the safe value of cast iron in tension, and may be used. Since this is a symmetrical section and ' since cast iron is much weaker in tension than in compression, the latter will not need to be investigated and the above figures can be accepted for the size of bed.
Page 39 - ... per second if the iron is of good quality and there are no serious cooling strains. In such wheels the bending due to centrifugal force is slight, and may safely be disregarded. 2. Rim joints midway between the arms are a serious defect and reduce the factor of safety very materially. Such joints...
Page 58 - SXE (1)] (2) where: P= maximum allowable working pressure. In pounds per square Inch. T= thickness of shell In Inches. S= minimum tensile strength of material In pounds per square Inch. R— Inside radius of shell In Inches. f— factor of safety, which Is 6. •E= efficiency of Join or ligament between tube holes, whichever Is the least. (2) Where seamless piping or tubing is used, the value of E shall equal 1, except...