Improvements in Steam Superheaters.
Year: 1893

page_text: Date of Application, 5th Dec., 1893-Accepted, 3rd Feb., 1894
COMPLETE SPECIFICATION.
Improvements in Steam Superheaters.
I, EUGENE DECK, of 87, Faubourg d'Altkirch, Mulhouse, (Alsace) in the
Empire of Germany, Civil Engineer, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
This invention relates to improvements in steam superheaters of the kind in
which the superheating of the steam is obtained by causing the latter to circulate
through a certain number of superheating sections analogous to Field tubes.
According to my invention cach section is constructed with two concentric tubes
traversed successively by the steam and one of which (the outer tube) is provided
with longitudinal ribs, placed close together, and extending nearly to the internal
tube, so that in circulating through the outer tube, that is to say, in the space
comprised between the walls of the two tubes, the steam will be caused to pass
in very thin streams so as to cause the whole of the steam to come in contact with
the heated wall.
The outer tubes of these superheating sections are closed at one end and formed
by preference of cast iron, and the internal tubes are open at both ends and are by
preference formed of iron or steel. The two tubes constituting each superheating
section are connected at the side of the open end of the outer tube with two con-
centric tubulures of a cast iron head, to which head can be connected a suitable
number of superheating sections, traversed successively by the steam, in order that
by its passage from one section to another, the steam may be violently agitated
whereby all the molecules of steam may be caused to come in contact with the
heated walls for the purpose of obtaining perfectly dry superheated steam,
without materially increasing the temperature and with a circulation relatively
restricted.
:-
In order to enable the invention to be fully understood I will describe the same
by reference to the accompanying drawing, in which :-
Figures 1 and 2 are views of my improved superheating apparatus without the
furnace..
Figures 3 and 4 shew the application of my improved superheater to the flue of
a steam boiler; and,
Figures 5 and 6 shew my improved superheating apparatus combined with an
independent furnace.
Referring to Figures 1 and 2 my improved superbeater comprises a head T,
of cast iron having an inlet A and an outlet B for the steain and as many
tubulures a, b; a², b²; a³, b³; as there are sections in the superheater, each formed
of two concentric tubes c¹, d'; c², d²; c³, d³.
Into the tubulures a', a², a³ formed by partitions in the head T, are screwed the
internal iron tubes c', c², open at both ends and to the tubulures 61, 62, 63 bolted
concentrically to the tubes c¹, c², c³ of the cast iron tubes d', d, d³ with or without
external wings m and provided internally with longitudinal ribs i, i, i placed close
together and enclosing, with very little play, the tubes c', c², c³; the cast iron tubes
are closed at the free ends by plates m¹, m², m³.
The steam entering at A traverses the first tube c¹ and passes at o into the
concentric cast iron tube d' which it traverses from o to s being divided into very
fine streams so as to cause the whole of the steam to come into contact with the
heated wall; at s the steam leaves the first section and passes into the second
heating section c, d where it is acted on in the same manner and so on in all

page_text: the other superheating sections to the last, which it quits through the outlet B of
the head T.
It will be understood that in passing from one section into another the steam
undergoes a violent agitation which alternating with the successive divisions into
thin streams in the tubes d', d, d³ causes all the molecules to come in direct contact
with the heated walls whereby perfectly dry steam is obtained without in any
way increasing the temperature and with a relatively restricted circulation.
The superheaters constructed in the manner just described can be placed in the
flues of steam boilers or can be employed with an independent furnace.
Figures 3 and 4 shew by way of example a superheater constructed according to
this invention placed in the flue of a steam boiler immediately behind the bridge M.
N and O in these figures indicate the pipes serving to convey the steam from the
dome R of the boiler and conduct it away from the superheater, these pipes being
connected together by the tubulures A and B of the superheater.
Figures 5 and 6 represent, by way of example, a superheater constructed
according to my invention heated by an independent furnace. In this arrangement
the superheater is placed in a chamber of masonry which is traversed by the
products of combustion from the furnace L and the steam to be superheated
traverses successively four superheating sections connected two by two to a head T,
a pipe K serving for the passage of the steam from one head to the other.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is 1
1. In a steam superheater having sections analogous to Field tubes, that is to say,
each formed of two concentric tubes successively traversed by steam, the internal
tube being open at both ends and the outer tube being closed at one end as herein
described, forming the outer tubes of the superheating sections with internal ribs
placed close together and extending almost to the internal tubes, so that in
between
traversing the outer tube of a similar superheating section, that is to
say,
the walls of the two concentric tubes the steam becomes divided into thin streams
whereby the whole of it comes into contact with the heated wall, the outer tube of
the superheating section being sometimes provided with external wings, substantially
as hereinbefore described.
2. In a steam superheater having superheating sections similar to Field tubes one
or more partitioned heads of cast iron with which the tubes constituting cach super-
heating section are connected, at the side receiving the 'open ends of the outer tubes,
to two concentric tubulures one of which is connected to a partition of the said
head or heads the partitions of the head or heads being arranged in such a manner,
that the steam is caused to successively traverse the various superheating sections
and being thereby subjected in its passage from one section to another to violent
agitation the molecules of steam are caused to come into contact with the heated
walls whereby superheated dry steam is obtained without materially augmenting
the temperature and with a relatively restricted circulation, substantially as herein-
before described.
Dated the 5th doo of December 1802
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.