Improvements in or connected with Steam Generators.
Year: 1898

page_text: Date of Application, 18th Nov., 1898-Accepted, 14th Jan., 1899
COMPLETE SPECIFICATION.
Improvements in or connected with Steam Generators.
I, HERMANN KASTRUP, Manager, of Brackwede, Westphalia, in the German
Empire, 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 the internal flues or fire tubes of steam generators and has
for its object to so construct and form the flue or fire tube that greater accommoda-
tion is provided for the grate and whereby the flame and heated gases are caused
to impinge upon the walls of the flue thereby increasing the efficiency of the
boiler.
Flues and fire tubes hitherto in use have been mostly of plain cylindrical form
and sometimes of plain tapered or conical form. In the former the flame and
heated gases pass mostly through the centre of the flue without impinging against
the walls but with a tapered Hue decreasing in diameter the flames must come
into contact with the flue walls and increased efficiency results.
According to my invention I combine with a flue of tapered or conical form a
corrugated surface. Such a flue is shown in the accompanying drawings of which
Fig. 1 is a longitudinal section and Fig. 2 a transverse section on line A B of
Fig. 1.
As will be seen from the drawings the flue is made up of several conical
corrugated tubular sections e e e of varying diameter riveted or otherwise suitably
secured together so as to form a tapering or conical corrugated flue or fire tube F.
By this construction of flue it will be seen that a considerable gain in efficiency
is obtained over cylindrical and plain conical or tapered flues as the furnace being
situated at the larger end of the flue the gradually decreasing diameter and
corrugations of the flue cause the flames to impinge against the sides thereof
whilst the corrugated and conical form increases the strength enabling flues of
less thickness and consequent weight to be employed compensating for any increased
cost of manufacture. The corrugations also provide a larger heating surface and
owing to the strength of the conical and corrugated form the flue may be con-
structed of considerably larger diameter than is usual allowing the use of grates
of the same area but of much shorter length than those at present employed.
Owing to the conical form the flue can be readily withdrawn for repairs by remov-
ing the rivets at the front and back ends.
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-In steam boilers and the like a flue or fire tube having corrugated or
undulated walls and tapering from end to end or of conical form, and comprised
of one or more conical or tapered sections suitably joined substantially as and
camin cat forth

page_text: 2The improved flue or fire tube for steam boilers and the like constructed,
arranged and adapted for use substantially in the manner and for the purposes
set forth.
1000
For the Applicant,
PRYOR & HARVEY,
3, St. Nicholas' Buildings, Newcastle-on-Tyne.