IMPROVEMENTS IN NON-CONDUCTING COMPOSITIONS FOR COVERING STEAM BOILERS, STEAM PIPES AND THE LIKE
Year: 1883

page_text: LETTERS PATENT to George Frederick Redfern of the General Patent Office,
4 South Street, Finsbury, in the County of Middlesex, Patent Agent for
an Invention of "IMPROVEMENTS IN NON-CONDUCTING COMPOSITIONS FOR
COVERING STEAM BOILERS, STEAM PIPES AND THE LIKE" A communication to
him from abroad by Henry Carr Goodell, of Atchison, in the county of
"
4 South Street, Finsbury, in the County of Middlesex, Patent Agent for
an Invention of "IMPROVEMENTS IN NON-CONDUCTING COMPOSITIONS FOR
COVERING STEAM BOILERS, STEAM PIPES AND THE LIKE A communication to
him from abroad by Henry Carr Goodell, of Atchison, in the county of
Atchison, state of Kansas, in the United States of America
COMPLETE SPECIFICATION filed by the said George Frederick Redfern at
the Office of the Commissioners of Patents on the 20th March 1883.
GEORGE FREDERICK REDFERN of the General Patent Office 4 South Street
Finsbury in the County of Middlesex, Patent Agent "IMPROVEMENTS IN NON-
CONDUCTING COMPOSITIONS FOR COVERING. STEAM BOILERS, STEAM PIPES AND THE
LIKE Communicated to me from abroad by Henry Carr Goodell of Atchison
in the county of Atchison, state of Kansas, in the United States of America.
"
The invention communicated to me relates to the covering of pipes, boilers and
like structures, and the object is to provide an economical covering, which shall at
the same time, be an effective means for preventing the escape and consequent loss
of heat by surface radiation or contact with other bodies, and shall be easily
applied.
The invention consists essentially of a plastic compound, composed of lamp black
with a fibrous or plastic material or either of them mixed therewith, and adapted
to be applied and to harden upon the surface of the pipe, boiler, or other structure
from or into which the passage of the heat is to be obstructed.
Hereinafter I have fully described the invention and the best means known to
me for the practical use and application of it
In Letters Patent of the United States reissued on the thirtieth day of
November one thousand eight hundred and eighty and numbered 9483 is described
a receptacle provided with double walls with a filling of lamp black to render the
walls as far as practicable impervious to the passage of caloric.

page_text: The loose lamp black, that is to say, lamp black in its ordinary condition unmixed
or with a percentage of fibrous material, is a non-conductor of heat, when placed
between double walls but it is not practicable so to apply the material upon
pipes which are used to convey steam, hot air, or for like purposes, nor upon the
outside shells of boilers, or other heat generators. Nor is it practicable to apply
the lamp black mixed with cement or lime alone, directly to the surface, by reason
of the lack of adhesiveness of the mixture. Further in order to give the best
results certain details of construction are essential or important, consisting in
applying the coating in two or more layers.
These are shewn in the accompanying drawing in which is represented a section
of part of a boiler shell coated in accordance with the invention.
In carrying out the invention when applying it to the coating of smooth boilers,
pipes, or like surfaces, the said surface is coated with a mixture to which when
applied the mixture containing the lamp black will adhere.
This coat consists of sixty five (65) parts of well slacked quick lime, thirty five
(35) parts of, crushed or ground asbestos, and enough of water to make a thick
mortar. The amount of asbestos may be increased under some circumstances to
give sufficient adhesiveness; some lamp black may be added to this first coat if
necessary.
This coating is applied directly to the pipe or other surface, the said surface
being preferably hot when so covered as the asbestos. sticks more readily to the
heated surface.
For a second coating take of well slacked quick lime forty (40) to fifty
(50) parts, of vegetable coarse fibre fifty (50) to sixty (60) parts; these ingredients
are mixed with water and brought to a proper temper, and afterwards is added to
them of lamp black from forty (40) to fifty (50) parts; the difficulty of penetrating
lamp black with water makes it necessary to first mix the other ingredients and
then to add the lamp black thereto. The body of the covering, that is to say, the
largest proportion of it is of this second composition just described. This notwith-
standing the large proportion of the lamp black which is not in itself adhesive,
will stick to the rough coating first applied, and it may be put on in any desired
It is not necessary
thickness corresponding to the degree of heat to be resisted.
to mix the asbestos fibre with this second coating as it will not ordinarily be
subjected to sufficient heat to destroy the vegetable fibre. Hair might be used
but not so well, as it is liable to lose its strength under the heat.
The second coating is put on with a trowel or some equivalent instrument, and
.when it is sufficiently dry, it is preferred to wrap it with well annealed wire in
circumstances where it can be done. This renders the coating solid and permanent.
For the underside of large surfaces it might be necessary to apply the wire before
the second coating, was all on, that is to say, after the first layer of it was put on as
it may be applied in several layers.
This would prevent sagging of the heavy body of coating.
After the second coating is applied, for a finish a third coating may be added
consisting of well slacked quick lime forty (40) to fifty (50) parts and of finely
ground fibre fifty (50) to sixty (60) parts thoroughly mixed with water with
thirty (30) to forty (40) parts of lamp black subsequently added.
Though I have specified particularly the parts, it will be understood that these
proportions are not necessarily to be adhered to closely but there may be variation
within considerable limits without material variation in the results. I have
specified what are considered to be the best proportions.
On a large oval surface for example much greater proportion of lamp black can
be used than on a small oval surface. It will be apparent that in many cases much
greater amount of adhesiveness will be required than in others, and the coating
may be varied accordingly. Under no circumstances need exactness or nicety be
used in mixing the parts.
Under some circumstances the third coating may be omitted where the first and
second would give sufficient protection and finish.

page_text: Instead of the lime, cement, plaster of Paris or any equivalents of these
substances may be used. For the vegetable fibre wood or paper pulp or the fibre
of other vegetable substances may be used
It is better to apply the mixture of asbestos and lime to the surface of the iron
in small quantities, like patch work at first instead of spreading it all on at once
like ordinary mortar. On very rough boilers this first coating might not be
necessary.
It has been found that a coating such as I have described from three fourths of
an inch to an inch and a quarter gave excellent results.
In the drawing I have represented the iron at a; the first coating at b, the
second coating at c, the wire coating is indicated at d, and the outer or finishing
coat at f
It is apparent that these coatings may be applied to steam boilers, steam and hot
air pipes, or any similar pipes or vessels.
It is in fact applicable to any situation where the passage of heat is to be
prevented, and would serve as a desirable plaster and roof covering for houses in
hot climates.
I am aware that most of the ingredients mentioned as composing the improved
covering are individually old and have been separately applied to like- purposes
before. It is not therefore intended to claim the use of such ingredients separately
but marked advantages have been found to arise from their use in the particular
relation and proportions described.
Having thus described the invention communicated to me and the best means of
carrying the same into effect what is claimed and intended to be protected by
Letters Patent is:-
Firstly. A non conducting covering for boilers and pipes and the like consisting
of a base or adhesive coating applied directly to the surface to be protected, com-
posed of slacked lime, cement or equivalent substance and asbestos in combination
with one or more outer coatings composed of lamp black and fibrous material
applied to the said base coating.
Secondly. A non conducting covering for pipes, boilers and the like consisting of
lamp black, slacked lime or cement and vegetable fibre in substantially the
proportions named.
In witness whereof I the said George Frederick Redfern have hereto set
my hand and seal this sixteenth day of March in the year of our Lord
one thousand eight hundred and eighty three
GF REDFERN (L.S.)