Year: 1896

page_text: I, FRANCIS RADOLIFFE, of 233 Burrago Road, Plumstend, in the County of
Kent, Chief Foreman of Forges, do hereby declare the nature of this invention to
be as follows:-
Forgings made in the usual way by stamping or pressing between surfaces or
dies having flat faces or one of which has a flat face and the other a vec-shaped
groove, whilst usually possessing sufficient tensile strength and ductility in a longi-
tudinal direction are deficient in these qualities in a transverse direction. This is
especially noticeable in light and heavy gun forgings where it is important that a
test piece of given length cut transversely from the forging and in a direction.
tangentially to the bore thereof shall possess a certain minimum amount of tensile
strength and ductility, and great difficulty has heretofore been experienced by
manufacturers in making such forgings of the required tensile strength and
ductility in a transverse direction to pass the required tests. This appears to be
due to the fact that whilst in the ordinary method of making forgings the metal is
caused to flow in a longitudinal direction and thereby caused to possess sufficient
strength and ductility in a corresponding direction, it is not caused to flow in a
circumferential direction with the result that it is deficient in tensile strength and
ductility in this direction.
Now my invention has for object to obviato in a simple and practical manner
the disadvantage above referred to. For this purpose I en form and arrange the
surfaces or dies between which the forging is to be subjected to pressure by
hammering or otherwise, that the forging will be formed with longitudinally
extending grooves or concavities at each pressing operation whereby the metal is
caused to flow more or less in a circumferential direction as well as in a longi-
tudinal directiou. For carrying out my invention the working surfaces of the
upper and lower dies between which the forging is worked may be each formed
with a longitudinal groove having at each side convex or rounded bearing surfaces
at such a distance apart that a forging compressed between the two dies will have
formed in it, at each operation, four longitudinal concave recesses arranged at
about equal distances apart.
In a modified arrangement the lower die is similar to that in the arrangement
just described but the upper die is provided on its underside with a single longi-
tudinal ridge or projection of convex form in cross section so that the forging will
have formed in it at each operation, threo longitudinal grooves of concave form in
cross section. The upper die may be carried by the hammer when the forging is
produced by hammering.
If desired the working surface of each of the dies may have more than two
convex or rounded bearing surfaces and in some cases they may be arranged
obliquely instead of longitudinally. Such bearing surfaces may be at right angles
to the direction of pressure or be inclined thereto.
By the means described, I have been able to entirely overcome the difficulty
heretofore experienced in producing forgings having the required degree of tensile
strength and ductility in a transverse direction.

page_text: My invention can be advantageously applied not only to the manufacture of
gun forgings but also of shafts for marine engines and of forgings for other
purposes.
Improvements in the Manufacture or Production of Forgings.
I, FRANCIS RADOLIFFE, of 233 Burrage Road, Plumstead, in the County of
Kent, Chief Foreman of Forges, do hereby declare the nature of this invention
aud in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement :-
Forgings made in the usual way by stamping or prossing between surfaces or
dies having flat faces or one of which has a flat face and the other a vee-shaped
groove the flat surfaces of which bear against the forgings, whilst usually
possessing sufficient tensile strength and ductility in a longitudinal direction, arc
deficient in these qualities in a transverse direction. This is especially noticeable
in light and heavy gun forgings where it is important that a test piece of given
length, cut trausversely from the forging and in a direction tangentially to the
bore thereof, shall possess a certain minimum amount of tensile strength and
ductility, and great difficulty has heretofore been experienced by manufacturers in
making such forgings of the required tensile strength and ductility in a transverse
direction to pass the required tests. This appears to be due to the fact that whilst
in the ordinary method of making forgings the metal is caused to flow in a longi-
tudinal direction and thereby caused to possess sufficient strength and ductility in
a corresponding direction, it is not caused to flow in a circumferential direction,
with the result that it is deficient in tensile strength and ductility in this
direction.
Now my invention has for object to obviate in a simple and practical manner
the disadvantage above referred to. For this purpose I so form and arrange the
surfaces or dies between which the forging is to be subjected to pressure by
hammering or otherwise, that the forging will be formed with longitudinally
extending grooves or concavities at each pressing operation whereby the metal is
caused to flow more or less in a circumferential direction as well as in a longitudinal
. direction.
Figs. 1 & 2 of the accompanying drawings show in front and side elevation one
construction of dies suitable for carrying out my invention, an ingot billet forging
being shown in between them. In this arrangement the working surfaces of the
upper and lower dies 1 and 2 between which the forging 3 is worked in the
ordinary way, are each formed with a longitudinal concave groove 4 having at
the sides thereof convex or rounded bearing surfaces 5 at such a distance apart
that the forging compressed between the two dies will at first have formed in it, at
each operation, four longitudinal concave grooves or recesses 6 arranged at about
equal distances apart, as shown in Fig. 3. At starting, the dies will be in the
relative positions shown approximately in Figs. 1 and 2. When a set of such
grooves or recesses have thus been formed, the forging is turned round on its axis
so that another set of grooves or recesses will be formed therain, this operation
being repeated in the ordinary way so as to gradually reduce the cross section, of
•
1

page_text: the forging to the required oxtent. As the cross section decreases, the convex or
rounded bearing surfaces 5 have less and less effect and when the cross section is
nearly reduced to the required amount, say to about half tho original cross section,
the compression is effected between the smooth concave surfaces of the grooves 4
the action of which serves to remove the irregularities previously produced in the
forging by the convex or rounded bearing surfaces 5 and to make the forging
smooth and round, the dies then assuming, at the end of the compression strokes,
the positions shown approximately in Figs. 4 and 5. For a forging that is to be
reduced in diameter say from about six inches to three inches, the bearing
surfaces 5 and the concave surface of the grooves 4 may be each struck with a
radius of about three inches. I however do not limit myself to any of the
dimensions herein stated.
By the means described, I have been able to entirely overcome the difficulty
beretofore experienced in producing forgings having the required degree of tensile
strength and ductility in a transverse direction, and also to lessen the time required
to reduce the forging to the required size.
My invention can advantageously be applied not only to the manufacture of
gun forgings but also of shafts for marine engines and of forgings for other
purposes.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what 1
claim is :-
The herein described improvement in the manufacture or production of forgings,
the surfaces or dies between which the forging is subjected to pressure being so
shaped and arranged that the forgings will be formed during the pressing operations
with grooves or concavities that extend longitudinally or lengthwise thereof
whereby the metal will be caused to flow more or less in a circumferential direction
as well as in a longitudinal direction, substantially as herein described for the
purpose specified.