Specification of William Brunton : steam engines and furnaces.

  • Brunton, William.
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: Specification of William Brunton : steam engines and furnaces. Source: Wellcome Collection.

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    Er unions Improvements in Steam Engines, Furnaces, §c. rising about eight inches above the said plane, thus forming (with the said plane and the above-mentioned two inches of the grate ring) a circular case for a circle of fire bricks all round the grate, which fire-bricks should be of such a height as to stand about six inches above the surface of the grate, for the o 5 lateral support of the fire. To the under side of the said grate ring is fixed a rim or cylinder (which I call the air ring), made of strong sheet iron, pro¬ jecting downwards about four inches into a circular trough of suitable diameter, made of cast iron, which trough is built into the brickwork of the ash-pit, and concentric with the said grate shaft. The said air ring is not suffered to touch 10 the bottom of the said trough, but moves in sand, with which the trough is filled. The use of the said air ring is to prevent the passage of air between the said grate ring and the said trough. The inside of the furnace or fire-place (made circular, as already noticed) is constructed concentric with the fire orate and about three inches more in diameter than the outside of the said 15 brick ring. The wall rises of this diameter from the level of the bottom of the said sand trough in which the said air ring is carried round by the said grate rino\ There is thus formed a cavity round the exterior of the said sand trough, to serve as a receptacle for any dust or ashes which may accidentally fall over the edge of the grate through the interstice of one inch and a half left all round 20 the said brick ring by the greater diameter of the furnace. Into the said cavity I make two or three or more openings at convenient places through the brickwork, with doors upon the same (to be kept open or shut at pleasure) for the double purpose of cleaning out the ashes and of permitting a current of atmospheric air to have access through the said interstice of one inch and a 25 half to the top of the fire to ignite the smoke. Through the wall of the fur¬ nace (which may be constructed of fire-bricks) an opening or flue is formed from the level of the top of the said brick ring, through which opening the flame passes to the boiler; and in the side opposite to this flue I usually place the fire door, which is of the common construction, and is uoed foi the lighting 30 and occasionally for cleaning the fire. In the roof of the furnace (which may also be of fire-bricks I construct a hole or opening (which I call the feeding hole) about five inches wide, one end of which is perpendicularly over the centre of the grate (or nearly so), and the other end over its circumference. Over the said feeding hole is placed the coal box (which I call the fire feeder, or, for bre- 35 vity, the feeder), which is made large enough to hold a supply of coal sufficient for one or more hours. This fire feeder is in shape similar to the hopper of a corn mill, excepting that the bottom is made oblong (its length being equal to half the diameter of the grate, as already stated), and its width about four inches more than the said feeding hole in the roof of the furnace, that is to say,