STEEL BOILERS.

The writer stated that his experience in the manufacture and working of

steel boilers was satisfactory. Many steel boilers of sizes varying from

six feet diameter to fourteen feet six inches diameter have left the

works at St. Peter's since 1877, when the first was made; and in no

case has there been a failure of a plate after being put into a boiler,

either in the process of manufacture or in working at sea. The mode

of working is as follows: For shell plates, from five-eighths inch

to seven-eighths inch thick, to warm each to a dark red heat before

rolling, having previously drilled a few holes to template for bolting

the strakes together; the longitudinal seams are usually lap joints

treble riveted, requiring the corners to be thinned, which is done after

rolling. The furnace plates are generally welded two plates in length,

and flanged to form Adamson rings, and at the back end to meet the tube

plate; the back flame-box plates are flanged, also the tube plates and

front and back plates; and wherever work is put on to the plate it

is annealed before going into the place. The rivet holes are drilled

throughout. In the putting together the longitudinal seams of the

thicker plates of the shells, great care is always taken to set the

upper and under plates for the lap to their proper angle before they

are bolted together, a point generally overlooked by the practical

boilersmith.

Scientific American Supplement, No. 299, September 24, 1881 · 第 36 / 111 题