Improvements in Metal Tubing.
Year: 1899

page_text: Date of Application, 16th May, 1899-Accepted, 12th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in Metal Tubing.
I, THOMAS MIDGLEY, of 310, Dublin Avenue, Columbus, in the State of Ohio,
United States of America, Artisan, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The present invention relates to tubing, has especial reference to that class
of tubing which is made of sheet metal and consists in certain improvements
in construction whereby tubing is made of multiple concentric sections of metal
metallically joined together and producing integral tubing as will be fully
disclosed in the following specification and claims.
In the accompanying drawings, which form part of this specification:-
Figure 1 represents a perspective view of two split tubes in position to be
assembled.
-
Fig. 2 is a transverse section of the tubes assembled.
Fig. 3 a like view of the completed tube.
Fig. 4 a side elevation of a modified form of the assembled tubing, with parts
broken away; and
Fig. 5 a transverse section of the tubing on line - Figure 4.
Reference being had to the drawings and the letters thereon, A indicates the
tubing made of sheet metal in multiple concentric open or split sections a b
which are formed of sheets of metal, such as steel or iron, preferably steel, bent
into tubular form with the edges c d abutting and are assembled or one pushed
into the other with the edges of one tube overlapping or out of line with the
edges of the other tube, and preferably opposite each other, as shown in Figs. 1
and 2. This disposition of the joints e of the tubes imparts strength and rigidity
to the tubing and reduces the possibility of leaking to a minimum.
The sections a b are made to fit closely, one within the other and may be of
different gage sheet metal, according to the weight and strength of tubing
required.
To produce a still heavier grade of tubing, the inner section a is surrounded
by a spirally wound section 61 and the outer section b encloses the two inner
sections, as shown in Figs. 3 and 4.
After the multiple sections have been assembled, the tubing is immersed in
a bath of molten metal, composed of copper and zinc or any suitable brazing or
soldering alloy and allowed to remain in the bath until it has become properly
heated and the liquid metal has thoroughly permeated and filled the joints in
the tubing and the sections have been permanently joined together by the
molten metal and the tubing coated with a non-corroding metal, preferably brass
on its interior and exterior surfaces g and f.
Tubing thus constructed, to all intents and purposes forms brass tubing, the
body of which is steel or iron and produces an article of manufacture which
can be substituted for brass tubing at a great reduction in cost and capable of
resisting greater strain and rough usage.
The tubing may be used for conducting fluids for various purposes and is

page_text: adapted for the general use of tubing, such as condenser and boiler tubes and
bicycle frames.
The ends of the tubing may be screw threaded or flanged for joining or con-
necting one piece to another in the usual manner.
When used for bicycle frames, the tubing is made slightly thicker than
required when finished, and after it has been metallically joined together in the
bath of molten metal, the outer coating g of metal from the bath is removed by
the use of acid or by abrasion and the tube drawn through a die and over a
mandril in the usual manner of finishing seamless tubing."
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed I declare that what I
claim is:-
1. Tubing composed of multiple concentric metallic sections, metallically
joined together and the inner surface coated with soft metal.
2. Tubing composed of multiple concentric metallic sections, of hard metal
joined together by an interposed body of soft metal and having the inner sur-
face coated with soft metal.
3. Tubing composed of multiple concentric metallic sections brazed together
and the inner surface coated with brass.
4. Tubing composed of multiple concentric metallic sections of hard metal
with their joints overlapping, metallically joined together and the inner surface
coated with soft metal.
5. Tubing composed of multiple concentric tubular metallic sections, one of
which is spiral and brazed together.
6. Tubing composed of inner and outer tubular metallic sections and an inter-
mediate spiral tubular section brazed together.
7. Tubing composed of multiple concentric tubular metallic sections, one of
which is spiral, brazed together and the inner surface coated with soft metal.
Dated this 15th day of May 1899.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.