Improvements in Steam Boiler Tubes, and in Machinery to be Employed in the Manufacture of the same.
Year: 1894

page_text: Date of Application, Zord Nov., 1894
Complete Specification Left. 12th July, 1895-Accepted, 17th Aug.. 1895
Date of Application, 2010 NOV., 1094
Complete Specification Left. 12th July, 1895-Accepted, 17th Aug.. 1895
PROVISIONAL SPECIFICATION.
Improvements in Steam Boiler Tubes, and in Machinery to be
Employed in the Manufacture of the same.
We, ROWLAND WATKIN LEWIS, and THOMAS SAMUEL LEWIS, and WILLIAM
HOWARD LEWIS, of Patent Tuhe Works, Monmore Green, Wolverhampton, in
the County of Stafford, Tube Manufacturers do hereby declare the nature of this
invention to be as follows:-
:-
Our invention has reference to the tubes of tubular steam boilers and consists in
making wrought iron or steel tubes of the kind hereinafter described for the said
boilers and also of improvements in machinery for manufacturing the said tubes.
In carrying our invention into effect we take cylindrical iron or steel tubes and
flute them with one, two or more inclined flutes, the said flutes being preferably
concave at bottom and convex at top the said flutes passing around the tube through
nearly but not quite its whole length thereby forming a tube twisted or corrugated
except at its ends.
Instead of making the flutes as described that is concave at bottom and convex
at top the said flutes may be angular instead of curved at top.
The said tubes are made preferably in the manner hereinafter described from
cylindrical or plain tubes, their ends being left or made cylindrical or unfluted for
the purpose of facilitating their fixing in the end plates of the boiler.
We prefer to manufacture the said tubes by means of a pair of rolls the said rolls
having formed upon their acting surfaces grooves or depressions of such form and
size as will produce the twisted or corrugated tube described. The ends of the
corrugated tubes may afterwards be made cylindrical. Or the ends of the tube
may be left uncorrugated by providing the rolls with cut away parts.
We do not however limit ourselves to the manufacture of the said tubes by the
machinery described as they may be otherwise made; for example, they may be
made by first corrugating a cylindrical tube longitudinally and then twisting the
said tube so as to give a helical figure to the corrugations; or, a plain or cylindrica!
tube may be drawn through a rotating die having the required figure to give the
desired twist or corrugation to it.
In making our improved tubes we prefer to operate upon the cylindrical tubes
in a heated state.
By the use of tubes of the kind described in steam boilers a large surface is
exposed to the flame and heated air passing through them and the said flame and
heated air strike more directly on the metal of the tubes than in cylindrical tubes
and the heat is thereby more effectually absorbed.
Dated the Twenty-third day of November 1804
W. T. WHITEMAN,
Agent for the Applicants.

page_text: Improvements in Steam Boiler Tubes, and in Machinery to be
Employed in the Manufacture of the same.
We, ROWLAND WATKIN LEWIS, and THOMAS SAMUEL LEWIS, and WILLIAM
HOWARD LEWIS, of Patent Tube Works, Monmore Green, Wolverhampton, in
the County of Stafford, Tube Manufacturers, do hereby declare the nature of our
invention and in what manner the same is to be performed to be particularl
described and ascertained in and by the following statement:-
Our invention has reference to the tubes of tubular steam boilers and consists in
making wrought iron or steel tubes of the kind hereinafter described for the aid
boilers and also of improvements in machinery for manufacturing the said tubes.
In carrying our invention into effect we take cylindrical iron or steel tubes and
flute them with one, two or more inclined flutes, the said flutes being preferably
concave at bottom and convex at top, the said flates passing around the tube
through nearly but not quite its whole length thereby forming a tube twisted or
corrugated except at its ends.
Instead of making the flutes as described, that is, concave at bottom and convex
at top the said flutes may be angular instead of curved at top.
The said tubes are made preferably in the manner hereinafter described from
cylindrical or plain tubes, their ends being left or made cylindrical or unfluted for
the purpose of facilitating their fixing in the end plates of the boiler.
We prefer to manufacture the said tubes by means of a pair of rolls the said rolls
having formed upon their acting surfaces, grooves or depressions of such form and
size as will produce the twisted or corrugated tube described. The ends of the
corrugated tubes may afterwards be made cylindrical. Or the ends of the tube
may be left uncorrugated by providing the rolls with cut away parts.
Figure 1 of the accompanying drawing represents a steam boiler tube made
according to our invention and Figure 2 represents the said tube as it comes from
the rolls, that is, before the flutes in the end portions (marked a, a in Figure 1)
have been obliterated and the said ends made plain or cylindrical as represented i
Figure 1.
Figure 3 represents a pair of rolls for producing tubes of the kind represented in
Figure 2 from plain or cylindrical tubes.
In making the said tube Figure 1 a plain or cylindrical tube of iron or steel is
heated to a bright red heat and is passed between the pair of rolls Figure 3 by the
action of which rolls the fluting of the said tube as represented in Figure 2 13
effected. The flutes at the ends of the tube Figure 2 are then obliterated so as to
leave the said ends plain as represented in Figure 1 by hammering the said ends of
the tube on a mandrel or otherwise.
The ends of the tube may however be lett plain or cylindrical instead of being
Auted and afterwards hammered to remove the flutes by making a portion of the
groove in each of the rolls plain, the said plain parts being coincident. Or the
said plain ends may be produced by raising the upper roll a sufficient distance to
permit of the passing of the end of the tube through the eye of the rolis to a distance
equal to the length of the required cylindrical end. The said upper roll is then
brought down and the tube rolled to near the rear end when the upper roll is again
raised out of action and the rear end of the tube thereby left plain.
We do not however linut ourselves to the manufacture of the said tubes by the
roils described and represented as they may be otherwise made; for example, they
may be made by first corrugating or fluting a cylindrical tube longitudinally and
then twisting the said tube so as to give a helical figure to the corrugations or

page_text: flutes; or, a plain or cylindrical tube may be drawn through a rotating die having
the required figure to give the desired twist or corrugation to it.
By the use of tubes of the kind described and represented in steam boilers, a
large surface is exposed to the flame and heated air passing through them and the
said flame and heated air strike more directly on the metal of the tubes than in
cylindrical tubes and the heat is thereby more effectually absorbed.
Tubes made according to our invention may either be used in the manufacture of
steam boilers in which the flame and heated air pass through the tubes or in the
manufacture of boilers in which the water circulates in the tubes, the flame and
heated air being external to the tubes.
Having now particularly described and ascertained the nature of our invention
and in what manner the same is to be performed we declare that we claim as our
invention of "Improvements in steam boiler tubes and in machinery to be employer
in the manufacture of the same.'
"
First. The improvements in steam boiler tubes made of iron or steel hereinbefore
described and illustrated in the accompanying drawing, the said improvements
consisting in forming the said iron or steel tubes with one, two or more helical or
twisted flutes extending through the greater part of their length, the ends being
left or made plain or cylindrical so as to facilitate the connection of the said tubes
with the boiler plates substantially as herein before described and illustrated.
Secondly. The use of a pair of rolls of the kind herein before described and
illustrated in Figure 3 of the accompanying drawing for forming from plain or
cylindrical iron or steel tubes, fluted tubes of the kind claimed in the prior claim;
that is to say, rolls the acting surface of each of which has the figure of a counter-
part of one half of the corrugated or fluted tube to be made the said counterpart
figure being formed in the cylindrical surface of the roll substantially as described
and illustrated.
Dated this Eighth day of July 1895
ROWLAND WATKIN LEWIS.
THOMAS SAMUEL LEWIS.
WILLIAM HOWARD LEWIS.