IMPROVEMENTS IN THE WEARING SURFACES OF STEAM AND OTHER ENGINES
Year: 1879

page_text: LETTERS PATENT to Loftus Perkins, of Seaford Street, in the County of
Middlesex, for the Invention of "IMPROVEMENTS IN THE WEARING SURFACES
OF STEAM AND OTHER ENGINES.”
Sealed the 1st June 1880, and dated the 23rd December 1879.
PROVISIONAL SPECIFICATION left by the said Loftus Perkins at the Office
of the Commissioners of Patents on the 23rd December 1879.
LOFTUS PERKINS, of Seaford Street, in the County of Middlesex.
MENTS IN THE WEARING SURFACES OF STEAM AND OTHER ENGINES."
"IMPROVE-
In the Specification of a formor Patent granted to me in the year 1872, No 3845,
I described the making packing rings for the pistons of steam engines and other
such like wearing surfaces of a hard metal composed of about 5 parts tin to 16
parts of copper. Packing rings and wearing surfaces formed of this metal work
admirably without any lubrication being necessary, but are costly owing to the
extremely hard and brittle nature of the metal, rendering it difficult to bring it to
shape by planing or turning. I have found that metal composed as described in the
above Specification will if heated to a red leat and then suddenly cooled by being
plunged into cold water or oil, or otherwise suddenly cooled, become thereby
softened and it can then be turned or planed just as readily as ordinary gun metal.
Thus the manufacture of packing rings and other wearing surfaces of this metal is
rendered easy, and packing rings and wearing surfaces formed of such soft metal
will work equally well without lubrication as wearing surfaces formed from such
metal in its hard and brittle state. I have also found that the metal after having
been softened as above described, may again be hardened by again heating it and
allowing it to cool slowly so that if it is desired that the wearing surfaces of such
inetal should be hard they may be shaped when the metal is soft and then be
afterwards hardened.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Loftus Perkins in the Great Seal Patent Office on the 23rd June
1880.
LOFTUS PERKINS, of Seaford Street, in the County of Middlesex.
MENTS IN THE WEARING SURFACES OF STEAM AND OTHER ENGINES."
" IMPROVE-
In the Specification of a former Patent granted to me in the year 1872, No. 3845,
I described the inaking packing rings for the pistons of steam engines, and other
[Price 2d.]

page_text: such like wearing surfaces of a hard metal composed of about 5 parts tin to 16
parts of copper.
Packing rings and wearing surfaces formed of this metal work admirably
without any lubrication being necessary, but aro costly owing to the extremely
hard and brittle nature of the metal, rendering it difficult to bring it to shape by
planing or turning. I have found that metal composed as described in the above
Specification will if heated to a red heat and then suddenly cooled by being
plunged into cold water or oil, or otherwise suddenly cooled, become thereby
softened, and it can then be turned or planed just as readily as ordinary gun metal.
Thus the manufacture of packing rings and other wearing surfaces of this metal is
rendered easy, and packing rings and wearing surfaces formed of such soft metal
will work equally well without lubrication as wearing surfaces formed from such
metal in its hard and brittle state. I have also found that the metal after having
been softened as above described may again be hardened by again heating it and
allowing it to cool slowly, so that if it is desired that the wearing surfaces of such
metal should be hard, they may be shaped when the metal is soft and then be
afterwards hardened.
In carrying out my Invention the wearing surface whether it be a packing ring
or other form of wearing surface is first cast approximately to the form desired,
from a mixture of about 5 parts tin to 16 parts copper. The copper and tin are
melted separately, the tin is then put into the melted copper and thoroughly
stirred and the mixture at once poured into the mould, either a sand or metal
mould may be used.
The packing ring or other wearing surface so cast approximately to form is when
removed from the mould beated to a temperature such that it appears luminous,
not more than blood red in the dark, and is then suddenly and altogether plunged
into cold water. When cool the packing ring or other wearing surface can in its
now softened state be turned or planed to the required form, and can afterwards be
used in this softened state as a packing ring or wearing surface. Preferably
however I again bring the metal back to its original hard condition before using it.
The packing ing or wearing surface is for this purpose again heated to such an
extent as to be luminous, not more than blood red in the dark, and is then allowed
to cool slowly in the air.
Having thus described the nature of my Invention and the manner of performing
the same, I would have it understood that I claim,―
First. The manufacture of packing rings and other wearing surfaces of steam
and other engines, from an alloy composed of about 5 parts tin to 16 parts copper
and softened, substantially as described.
Second. The manufacture of packing rings and other wearing surfaces of steam
and other engines from an alloy composed of about 5 parts tin to 16 parts copper,
softened as described to allow of their being turned or planed to the form required
and after they have been brought to the shape required again hardened, sub-
stantially as described.
In witness whereof, I, the said Loftus Perkins, have hereunto set my hand
and seal, this Twenty second day of June, in the year of our Lord One
thousand eight hundred and eighty.