IMPROVE- MENTS IN THE MANUFACTURE OF CHAINS AND CHAIN CABLES, AND IN THE MACHINERY THEREFOR
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by the said Thomas Murray Gladstone
at the Office of the Commissioners of Patents, with his Petition, on the
20th November 1866.
I, THOMAS MURRAY GLADSTONE, Civil and Consulting Engineer, of York
Chambers, Adelphi, Strand, in the City of Westminster, in the County of
Middlesex, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE MANUFACTURE OF CHAINS AND CHAIN CABLES, AND IN THE MACHINERY
THEREFOR," to be as follows:-
I make a chain, the links of which are of the form shown on Plate 1,
Fig. 1, the parts being double when compared with the chain links, as ordi-
narily made, hence I call it a "duplex chain." I take No. 3 bar or charcoal
"iron" or "soft steel," or other suitable metal, and cut the same into separate
lengths according to their sizes, and of about 46 times their diameter (which
will be found a most suitable proportion), and I place each of these lengths,
heated or otherwise, in a machine similar in action to a punching or a shearing
machine, but which has a tool that presses upon the same when laid upon
block and so removes each length from a straight line into a curve or form, as
shown in Fig. 2. It being thus made to have two almost parallel sides it is
ready for the smith to weld at the open ends, so that after scarfing and
rounding the two points with the hammer it assumes the condition of a single
link, as shown in Fig. 3; it is then (after being welded) placed in a machine
similar to the former one in Fig. 2, but having a tool and block suitable to
bend the link into the form, as shown in Fig. 4. A quantity of these separate

page_text: links so formed I put into a heating furnace; when being heated the smith
can close one end of each link, and having inserted the open end into one of
the others he can close the opposite end, and by adding link to link make a
continuous chain, as shown in Fig. 1. Studs of the form (as shown in one
link marked B, Fig. 1, and in Fig. 5) may be used, but I prefer chains
without any studs, since should any chain be used to so great a strain as to
make the links rigid and no longer pliable it is desirable not to use but to
destroy such chain, it having sustained an undue force by being deprived of
that elasticity which is advisable. and needful in every reliable chain. In
order to know and be assured of a proper margin to be contained in any or
every such chain or chains beyond the Admiralty scale of test it is desirable
that there should be at least some links promiscuously taken out of every
hundred fathoms, and such links should be broken in a proving machine, and
if the same shall not sustain 50 per cent. pressure beyond the Admiralty scale
of test the said chain or chains to be condemned as untrustworthy. Such
chains compared with the ordinary chains will be found much more safe and
strong from the welds generally in the ordinary form of chain links being the
weakest part, while the welds of these chains being only one of the two
diameters of the iron and the other half solid (as shown in the Drawings and
marked A) the risk of their having any defect in the welds when compared
with the ordinary chain links is reduced by one-half. As chains thus made
will be found stronger than any ordinary, chains of like quality of metal and of
equal weight per fathom it is necessary that all the joining shackles and any
attachments thereto should be proportionally stronger than those used in single-
sided chains. I also attach to each chain (if to be used as a chain cable) two:
shackles having a double swivel, as shown in Plate 2, Figs. 6 and 7, to be
used next to the anchor, whereby any twist or kink to which every chain is
liable will be readily removed, and so increased security be given.
Now I claim as my Invention the method set forth for making the "duplex
chains," and the machinery for that purpose, whether such machinery is acted
upon by any simple lever, crank, excentric, hydraulic pressure, or by steam
power, and thereby economically producing the results set forth, and which
can be performed by any ordinary workman.
.