Specification of Arthur Woolf : steam and other boilers.

  • Woolf, Arthur.
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Arthur Woolf : steam and other boilers. Source: Wellcome Collection.

    12/24 (page 10)
    Woolfs Improved Apparatus for Converting Water, §c. into Steam. for the rod of the valve, so contrived as to answer the purpose of a stuffing box, to make the rod work up and down steam-tight, the stuffing being kept in its place by means of the male screw which works in the female screw that forms the stuffing box, as shewn in the section. By means of a pin or nail b, and the two vertical pieces e, e, or by any other convenient means, the 5 piston rod is made fast to m, which is a cover of and joined to the hollow cylinder n9 n. The cover m fits steam-tight into the collar o, o, which is made fast in C by cement or otherwise. The cylinder n, n9 is open at the bottom, having a free communication with A, the main cylinder of one of my boilers, and has two, three, or more vertical slits, one of which, S, is shewn in the 10 Drawing. The sum of the surface of all these slits or openings should be equal to the area of the opening of the collar o, o, in which the cylinder ??, n, works. When the steam acquires a sufficient degree of elastic force to raise the valve (that is, the cylinder n, n, with its cover m, and the rod R, R), and whatever weight it may be loaded with, then the openings S, getting above the 15 steam-tight collar o, o, allows the steam to pass into the steam box C, and the quantity of steam that passes will be proportioned to the elastic force it has acquired, and the weight with which the valve is loaded, and the rise of the open¬ ings S above the collar o, o, will be in the same proportion. This valve may be loaded in any of the usual methods, but I prefer the one shewn in the 20 Drawing, in which the upper part of the rod R, R, is made in the form of a rack, working in a segment of a wheel W, which carries an arm the axis of which is represented by the line L, W, which carries a weight Z, that may be moved near to or farther from the centre of the wheel W, according as the pressure of the valve is wished to be increased or diminished. As the 25 valve rises, the weight moves upwards in the arch n9 n, giving an increased resistance to the farther rising of the valve proportioned to the greater hori¬ zontal distance from the centre W, which the weight attains by its rise in the said arch, the said distance being measured in the line W,p, by a perpendicular from the said line W, p, passing through the centre of the weight. Thus, if 30 the weight Z press with a force equal to twenty pounds on the square inch of the aperture in o, o, in its present position in the line W, L, it will, when it rises to the position at i, press with a force equal to thirty pounds, and at p, with a force equal to forty pounds on the square inch; so that the rod L, W, may be made to serve at the same time as an index to the person who attends 35 the fire, nothing more being necessary for this purpose than to graduate the arch described by the end L of the rod W, L. In the side of the steam box C, there is an opening N, to allow the steam to pass from it by a pipe