_For one Horizontal Tubular Boiler_ 72 _inches diameter_ 18
_feet long for_…………………_of_………
Type.
The boiler to be of the Horizontal Tubular type with all castings and
mountings complete.
Dimensions.
Boiler 72 inches diameter and 18 feet long. Each boiler to contain 90
best lap welded tubes 3-1/2 inches diameter by 18 feet long, set in
vertical and horizontal rows with a space between them vertically and
horizontally of no less than one inch and one-quarter (1-1/4) except
central vertical space, which is to be three inches (3). No tube to
be nearer than two and one-half inches (2-1/2) to shell or boiler.
Holes through heads to be neatly chamfered off. All tubes to be set
by Dudgeon Expander and slightly flared at front end, turned over and
beaded down at back end.
Quality and Thickness of Steel Plates.
Shell plates to be 1/2-inch thick of homogeneous steel of uniform
quality having a tensile strength of not less than 65,000 lbs. Name of
maker, brand and tensile strength to be plainly stamped on each plate.
Heads to be of same quality as plates of shell in all particulars
3/4-inch thick. Bottom of shell to be of one plate, and no plate to be
less than 7 feet wide. Top of shell to be in three plates. All plates
planed before rolling, and all joints fullered not caulked.
Flanges.
All flanges to be turned in a neat manner to an internal radius of not
less than two inches (2) and to be clear of cracks, checks or flaws.
Riveting.
Boilers to be riveted with 3/4-inch rivet throughout. All girth seams
to be double riveted. All horizontal seams to be double riveted. Rivet
holes to be punched or drilled so as to come fair in construction. No
drift pins to be used in construction of the boilers.
Braces.
All braces to be of the crowfoot pattern, one and one eighth (1-1/8)
inch diameter and the shortest to be no less than four feet (4) long
and of sufficient number for thorough bracing, and to bear uniform
tension.
Manholes, Hand Holes and Thimbles.
One manhole in top of each boiler with heavy cast iron frame riveted on
middle of centre plate; one manhole near the bottom of each front head;
head reinforced with a wrought iron ring two inches (2) square, riveted
to heads with flush countersunk rivets two inches (2) pitch and to
have all the necessary bolts, plates, guards and gaskets; two six-inch
thimbles riveted to top of each boiler, each to have a planed face;
one heavy 6-inch flange on bottom of each boiler, 12 inches from back
end to centre of flange. There must be two braces, one on each side of
manhole in front head; also to have three braces opposite manhole on
back head below tubes.
Lugs.
Four (4) lugs riveted on each side of boilers, of good and sufficient
size, with six one-inch rivets in each lug.
Castings.
Each boiler to have a complete set of castings consisting of ornamental
flush fronts containing tube, fire and ash-pit doors, and provide
the best stationary grate bars as may be selected by buyer, with the
necessary fixtures, all bearing bars, britching plates, dead plates,
binder bars, back cleaning out doors with frames. Anchor bolts and
buck stays. The fire door to contain adjustable air opening and to be
protected with fire shields. One heavy cast iron arch over each boiler.
Testing.
Boilers to be tested with a water pressure of 200 lbs. per square inch
and certificate of such test having been made shall be furnished with
boiler. Test of boiler to be under direction of such steam boiler
Insurance Company as may be selected by buyer.
Quality and Workmanship.
All boilers to be made in the best workmanlike manner and all material
of their respective kinds to be of the best, and in strict accordance
with specification.
Fittings and Mountings.
The boiler to be furnished with the following: One four inch heavy
mounted safety valve. One six inch flanged globe valve. Two two inch
best globe valves. Two two inch check valves. One eight inch dial
nickel plated steam gauge. One low water alarm gauge. One set of fire
irons for two boilers consisting of hoe, poker, slice bar and shovel.
Drawings.
All drawings furnished for masons in setting the boilers.
Duty of Boiler.
The boiler to develop 120 horse power and to work under a constant
pressure varying from 125 to 150 lbs. to the square inch.
All rivets are to be 2-1/2 and 1-1/2 inch pitch. The pitch line of the
rivets to be not nearer 1-1/8 inches to the edge of the sheet.
To be 8 lug plates for each boiler not less than 2 feet long, 8 inches
wide, and one inch thick.
There shall be six 1 inch anchor rods running front to rear of each
boiler, in the brick work.
These boilers and all their fronts, fittings and connections will be
subject to the inspection of…………………