SHOP PRACTICE
ROLLING MILLS AT SCRAP DOCKS
At the annual meeting of the Railway Storekeepers' Associa
tion, G. G. Allen of the Chicago, Milwaukee & St. Paul read a
paper on "Rolfing Mills al Railway Scrap Docks--Economy Li.
fected, an abstract of which inllows:
The C. M. & St. I. has, for many years, manufactured praz
tically all of its freight cars and a large proportion of its loco-
motives, and one of the best methods we have found for em-
ploying the rolling mill is to select the scrap, old arch bars, rods,
etc., shear them to the proper size, and roll them for special parts
that enter into the construction of this new equipment, such as
brake hangers, carry irons, brake jaws, bolts, etc., that are re-
quired in very large quantities.
Thousands of drift holts for the bridge and building depart
ment are made from re-rolled iron, in fact comparatively little
new iron is used for common hoits for any class of work.
The mill was located in the blacksmith shop chiefly for the
reason that there was no room, nor were there facilities for
doing this work on the scrap dock. and owing to the practice of
utilizing the product of the mill for special purposes, a great deal
et the iron is worked up in the same shop just as it comes from
the mill, and the scrap from the shears, both from the original
bar, as well as the enttings from the finished bar, is used also, in
the same shop, in the hammer furnaces. The blacksmith shop
location under these conditions is a convenient one, but as a
general proposition for reads that have modern scrap docks,
equipped with power, hammers, shears, etc., and where the mak-
ing of special parts is not the rule the scrap dock is unquestion-
ably the proper location,
The hillets used are from 12 to 24 in. long and the output of
the machine varies from three to six tons per day, depending
on the size of the material rolled. The total cost of operation is
$18.35 a day
Various tests made from time to time have demonstrated the
fact that the re-rolled iron is of good quality and usually superior
to the ordinary grades of new iron, the improvement being due
to the additional rolling.
In computing costs and figuring profits, we have endeavored
to be conservative. Scrap has always been charged at higher
that market prices and all legitimate items of expense added.
The cost of re-rolling, not including value of serap, is from $3
to $6 per tor: according to size of iron rolled, and the profits will
average $10 per ton.
The net saving oi a similar mill at the Burnside shop of the
Illinois Central is reported to amcunt to well over $12 per ton,
everything considered except interest on the money invested and
the steam consumption. There are no depreciation charges. The
present average daily outpat is three and one-half tons. Cost for
labor and fucl $4 to $4.75 per ton, and profits $700 to $900 per
month.
The Chicago & North Western is also operating a mill of the
C. M. & St. P. type at the Chicago shops, reducing 14 in. and
1½ in. round bars to in. and 4 in. The daily output is one
and one-half ions at a cost of about $ per ton. In adidlica they
have ordered an Ajax three-roll mill, which will have a capacity
of from 2 in. to 3 in. It is the intention to operate hoth mills.
The Chesapeake & Ohio has an Ajax reclaiming roll on its
scrap dock at 13untington, W. Va. The total cost of rolls, fur-
naces, oil tanks, shed, motor, etc., was in the neighborhood of
$12,000. The average daily ontunt is three and one-half tons on
which it is stated they are making a profit of $1,100 per month.
The Southern Paciuc Company is operating a rolling mill on
the scrap dock at the Sacramento shops, with a maximum output
of 1940 tons and average output of 90 tons per day. The total cust
per con including scrap is $28.00, and the total prolits are $56.000
a year. This, however, would hardly he considered a re-rolling
mill proposition, but a general rolling mill.
As the difference between the market price of new iron and
the market price of scrap is not always maintained at the same
level, the profits from the operation of re-rolling mills must
necessarily vary. The greater this difference, the greater the
prodit, but with sufficient tonnage to keep a mill steadily em-
ployed and manned by regular crew, the profits from such a
mill as have described, having a capacity of from three to six
tous per day. should unt, at any line, be less than $10 per ton.
The question, therefore, of the economy to be effected by the
installation of re-rolling mills at railroad scrap docks is one that
each road can readily decide for itself, depending on whether or
not it has sufficient accumulation of old material suitable for
re-rolling, the present disposition of which is not bringing a
return that will compare favorably with the above figures.
DISCUSSION.
W. O. Thompson described the arrangement and proposed op-
eration of a large reclaiming shop that is soon to be built by ons
of the largest railways. The facilities to be provided are elabor-
ate and well arranged.
A point was raised as to the advisability of using the rolling
mills at scrap ducks with billets and making new material di-
rect. The consensus of opinion seemed to be that this would not
be an economical practice. One member reported that $960,000
worth of material had been reclaimed with a re-rolling mill at a
total cost of about half the value of new material.
EXHAUST SYSTEMS FOR GRINDING
WHEELS
The New York State Department of Labor has issued specifi-
catious for the design, construction and operation of exhaust
systems for grinding, polishing and buffing wheels. These specifi-
cations were prepared by William Newell, mechanical engineer
of the department of lahor, and the more important items are
as follows:
Minimum sizes of branch pipes allowed for different size
emery or other grinding wheels are given in the accompanying
table:
Diameter of wheels.
6 in, or less, not over in, thick.
7. to 9 in. inclusive, not over 1½ in. thick.
10 in. to 16 in. inclusive, not over 2 in. ɩbick.
17 in. to 19 in. inclusive, not over 3 in. thick..
20 in. tn 24 i. imelsive, not over in. thick,
25 in. to 30 in. inclusive, tot ver 5 in. thick..
Maximum
grinding
Minimum
diameter
of branch
sq. in.
pice in in.
19
3
43
3½
101
4
- 80
4½ 302 973 In case a wheel is thicker than given in this tabulation, cr ii a disc instead of a regular wheel is used, it must have a branch pipe ne smaller than is called for by its grinding surface, as given. Minimum sizes ni branch pipes allowed for different size buff- ing, polishing, or rag wheels, as they are variously called, are given in the table. Diameter of wheels, 6. or less, not over 1 in. thick.. 7 in. in 12 in. inclusive, not over 1% in thicke. 13 in, to 16 in. inclusive, nut over 2 in. thick.. 17 in. to 20 in. inclusive. ut over 3 in. thick.. 21 jr. to 24 in. inclusive, not over 4 in. thick.. 25 in. to 40 in. inclusive, not over 5 in. thick.. Maximum Minimum grinding surface. sq. in. diameter of licancls pipes in in. 19 5% 57 2 101 456 189 302 472 5 20% The thickness given in this table for buffing wheels applies to the thickness of the wheel at the center. In case the wheel 305
