VIEW THE MOBILE VERSION of www.steelmaking.ca Informational Site Network Informational
Privacy
   Home - Steel Making - Categories - Manufacturing and the Economy of Machinery

Steel Making

Steel Worked In Austenitic State
As a general rule steel should be worked when it is in the a...

Testing And Inspection Of Heat Treatment
The hard parts of the gear must be so hard that a new mill f...

Placing Of Pyrometers
When installing a pyrometer, care should be taken that it re...

Hardening High-speed Steel
In forging use coke for fuel in the forge. Heat steel slowly ...

Shrinking And Enlarging Work
Steel can be shrunk or enlarged by proper heating and cooling...

The Penetration Of Carbon
Carburized mild steel is used to a great extent in the manufa...

Instructions For Working High-speed Steel
Owing to the wide variations in the composition of high-speed...

Highly Stressed Parts
The highly stressed parts on the Liberty engine consisted of ...

Plant For Forging Rifle Barrels
The forging of rifle barrels in large quantities and heat-tre...

Properties Of Steel
Steels are known by certain tests. Early tests were more or l...

Quality And Structure
The quality of high-speed steel is dependent to a very great ...

Suggestions For Handling High-speed Steels
The following suggestions for handling high-speed steels are ...

Chromium
Chromium when alloyed with steel, has the characteristic func...

Carburizing By Gas
The process of carburizing by gas, briefly mentioned on page ...

Quenching
It is considered good practice to quench alloy steels from th...

Steel Before The 1850's
In spite of a rapid increase in the use of machines and the ...

Effects Of Proper Annealing
Proper annealing of low-carbon steels causes a complete solu...

Conclusions
Martien was probably never a serious contender for the honor ...

Rate Of Cooling
At the option of the manufacturer, the above treatment of gea...

Oil-hardening Steel
Heat slowly and uniformly to 1,450 deg.F. and forge thorough...



Making Steel Balls






Category: THE FORGING OF STEEL

Steel balls are made from rods or coils according to size, stock
less than 9/16-in. comes in coils. Stock 5/8-in. and larger comes
in rods. Ball stock is designated in thousandths so that 5/8-in.
rods are known as 0.625-in. stock.

Steel for making balls of average size is made up of:

Carbon 0.95 to 1.05 per cent
Silicon 0.20 to 0.35 per cent
Manganese 0.30 to 0.45 per cent
Chromium 0.35 to 0.45 per cent
Sulphur and phosphorus not to exceed 0.025 per cent

For the larger sizes a typical analysis is:

Carbon 1.02 per cent
Silicon 0.21 per cent
Manganese 0.40 per cent
Chromium 0.65 per cent
Sulphur 0.026 per cent
Phosphorus 0.014 per cent

Balls 5/8 in. and below are formed cold on upsetting or heading
machines, the stock use is as follows:

TABLE 14.--SIZES OF STOCK FOR FORMING BALLS ON HEADER
-------------------------------------------------------
Diameter of Diameter of Diameter of Diameter of
ball, inch stock inch ball, inch stock, inch
----------------------------------------------------
1/8 0.100 5/16 0.235
5/32 0.120 3/8 0.275
3/16 0.145 7/16 0.320
7/32 0.170 1/2 0.365
1/4 0.190 9/16 0.395
9/32 0.220 5/8 0.440
-------------------------------------------------------

For larger balls the blanks are hot-forged from straight bars.
They are usually forged in multiples of four under a spring hammer
and then separated by a suitable punching or shearing die in a
press adjoining the hammer. The dimensions are:

-----------------------------------------------------------
Diameter of ball, Diameter of die, Diameter of stock,
inch inch inch
---------------------------------------------------------
3/4 0.775 0.625
7/8 0.905 0.729
1 1.035 0.823
-----------------------------------------------------------

Before hardening, the balls are annealed to relieve the stresses
of forging and grinding, this being done by passing them through a
revolving retort made of nichrome or other heat-resisting substance.
The annealing temperature is 1,300 deg.F.

The hardening temperature is from 1,425 to 1,475 deg.F. according to
size and composition of steel. Small balls, 5/16 and under, are
quenched in oil, the larger sizes in water. In some special cases
brine is used. Quenching small balls in water is too great a shock
as the small volume is cooled clear through almost instantly. The
larger balls have metal enough to cool more slowly.

Balls which are cooled in either water or brine are boiled in water
for 2 hr. to relieve internal stresses, after which the balls are
finished by dry-grinding and oil-grinding.

The ball makers have an interesting method of testing stock for
seams which do not show in the rod or wire. The Hoover Steel Ball
Company cut off pieces of rod or wire 7/16 in. long and subject
them to an end pressure of from 20,000 to 50,000 lb. A pressure
of 20,000 lb. compresses the piece to 3/16 in. and the 50,000 lb.
pressure to 3/32 in. This opens any seam which may exist but a
solid bar shows no seam.

Another method which has proved very successful is to pass the
bar or rod to be tested through a solenoid electro-magnet. With
suitable instruments it is claimed that this is an almost infallible
test as the instruments show at once when a seam or flaw is present
in the bar.





Next: The Forging Of Steel

Previous: Heat Treatment Of Axles



Add to del.icio.us Add to Reddit Add to Digg Add to Del.icio.us Add to Google Add to Twitter Add to Stumble Upon
Add to Informational Site Network
Report
Privacy
SHAREADD TO EBOOK


Viewed 4664