Description of Richards' Improved Steam-engine Indicator with Directions for Its UseLongmans, Green, 1868 - 134 pagina's |
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Description of Richards' improved Steam-Engine Indicator; with directions ... Charles Talbot PORTER Volledige weergave - 1869 |
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acceleration action angle Area in Sq ascertain atmo Atmosphere at 32 atmospheric line boiler centrifugal force có có có commencement compression condensing engines connecting-rod cord counter-pressure crank Cubic Foot cylinder Decimals density diagram Diameter in Inches distance Elastic Force employed expansion curve fall of pressure feet per minute friction high speeds horse-powers imparted Inches of Mercury increase Indicator Indicator diagram instrument Joule Latent Heat length line of perfect lines drawn mean pressure measured Mercury at 32 Millimètres of Mercury moving multiplied non-condensing engines number of revolutions obtained paper pencil perfect vacuum point of cut-off point of release port pounds power exerted pressure of steam reciprocating Regnault represent resistance retardation return stroke revolutions per minute scale screw Sensible Heat shown Specific Gravity speed of piston spring square inch steam-line supposed TABLE taken temperature total heat units of heat velocity versed sine volume weight of water
Populaire passages
Pagina 55 - OR WELL. Multiply the square of the diameter in inches by the decimal .7854, and this product by the depth in inches ; divide this product by 231, and the quotient will be the contents in gallon^ EXAMPLE.
Pagina 23 - This is owing to the difference in the speed of the piston at the opposite ends of the cylinder, which is, at the outer end of a direct-acting engine, from 35 per cent to 66 per cent greater than at the crank end, the difference varying according to the degree of angular vibration of the connecting-rod. In side-lever or beam-engines, these proportions are reversed, and the speed of the piston is greater at the upper end of the cylinder. Often also there is a difference in the lengths of the thoroughfares,...
Pagina 28 - ... spring, then bend the paper round the cylinder, and insert the other corner between the springs. The paper should be long enough to let each end project at least half an inch between the springs. Take the two projecting ends with the thumb and finger, and draw the paper down, taking care that it lies quite smooth and tight, and that the corners come fairly together, and replace the cylinder. The spring used on this Indicator for holding the paper will be found preferable to the hinged clamp....
Pagina 33 - ... square inch of the piston, or, more accurately, the excess of pressure on the acting side of the piston to produce motion, over that on the opposite side to resist it. It is of no consequence, in this respect, what the character of the diagram may be, whether most wasteful, like the one shown in fig. 13, page 88, or most economical, like fig.
Pagina 38 - ... decimals, or divide their sum by the number of divisions, if there are more than 10, and the quotient will be the mean pressure above the atmosphere during the stroke. Then repeat the process for the area between the atmospheric line, or the expansion curve after it has crossed this line, and the lower outline of the diagram. Add the two mean pressures so ascertained together, then find in Table No.
Pagina 10 - The diagram thus described shows on inspection the following particulars, viz. : what proportion of the boiler-pressure is obtained in the cylinder — how early in the stroke the highest pressure is reached — how well it is maintained — at what point, and at what pressure, the steam is cut off — whether it is cut off sharply, or in what degree it is wire-drawn — at what point, and at what pressure, it is released — in a non-condensing engine, whether it is freely discharged, or what proportion...
Pagina 56 - Table the logarithm of the number nearest to the quotient, and to this add 1 ; the sum is the ratio of the gain. Then find the terminal pressure, by dividing the initial pressure by the proportion of the stroke during which the steam is admitted, and multiply it by the logarithm + 1 found as above ; the product will be the mean pressure through the stroke.
Pagina 38 - ... pressure will come a little above the atmospheric line, but it is more convenient, and answers all the purposes of the diagram better, to measure each way from the latter. The space above the steam line and between this and the line of boiler pressure shows how much the pressure is reduced in the cylinder by throttling, or by the insufficient area of the ports, proper allowance being made for the difference of pressure necessary to give the required motion to the steam in the pipe ; whilst the...
Pagina 28 - ... one to fix the paper very readily. The marking-point should be fine and smooth, so as to draw a fine line, but not cut the paper. It may be made of a brass wire ; the best material is gun-metal, which keeps sharp for a long time, and the line made by it is very durable. Lines drawn by German silver points are liable to fade. A large-sized common pin, a little blunted, answers for a marking-point very well indeed ; a small file and bit of emery cloth used occasionally will keep the point in order.
Pagina 28 - ... length, and taken up from time to time, as it may become stretched by use. On high-speed engines, it is as well, instead of using this, to adjust the cord and take up the stretching, as it takes place, by tying knots in the cord. If the cord becomes wet and shrinks, the knots may need to be untied, but this rarely happens. The length of the diagram drawn at high speeds should not exceed four and...