VIEW THE MOBILE VERSION of Informational Site Network Informational
   Home - Steel Making - Categories - Manufacturing and the Economy of Machinery

Steel Making

Restoring Overheated Steel
The effect of heat treatment on overheated steel is shown gra...

Heating Of Manganese Steel
Another form of heat-treating furnace is that which is used ...

Carbon Steels For Different Tools
All users of tool steels should carefully study the different...

PHOSPHORUS is an element (symbol P) which enters the metal fr...

An Automatic Temperature Control Pyrometer
Automatic temperature control instruments are similar to the ...

Introduction Of Carbon
The matter to which these notes are primarily directed is the...

Ebbw Vale And The Bessemer Process
After his British Association address in August 1856, Besseme...

Drop Forging Dies
The kind of steel used in the die of course influences the he...

Pickling The Forgings
The forgings were then pickled in a hot solution of either ni...

There is no mystery or secret about the proper annealing of d...

Reheating for machine ability was done at 100 deg. less than ...

Complete Calibration Of Pyrometers
For the complete calibration of a thermo-couple of unknown e...

SULPHUR is another element (symbol S) which is always found i...

Annealing Of High-speed Steel
For annealing high-speed steel, some makers recommend using g...

Short Method Of Treatment
In the new method, the packed pots are run into the case-har...

Hardening Operation
Hardening a gear is accomplished as follows: The gear is tak...

A combination of the characteristics of nickel and the charac...

Heat-treating Department
The heat-treating department occupies an L-shaped building. ...

Care In Annealing
Not only will benefits in machining be found by careful anne...

Heavy Forging Practice
In heavy forging practice where the metal is being worked at...

Fatigue Tests


It has been known for fifty years that a beam or rod would fail
at a relatively low stress if only repeated often enough. It has
been found, however, that each material possesses a limiting stress,
or endurance limit, within which it is safe, no matter how often
the loading occurs. That limiting stress for all steels so far
investigated causes fracture below 10 million reversals. In other
words, a steel which will not break before 10,000,000 reversals
can confidently be expected to endure 100,000,000, and doubtless
into the billions.

About the only way to test one piece such a large number of times
is to fashion it into a beam, load it, and then turn the beam in
its supports. Thus the stress in the outer fibers of the bar varies
from a maximum stretch through zero to a maximum compression, and
back again. A simple machine of this sort is shown in Fig. 10,
where B and E are bearings, A the test piece, turned slightly
down in the center, C and D ball bearings supporting a load
W. K is a pulley for driving the machine and N is a counter.

Next: Hardness Testing

Previous: Impact Tests

Add to Add to Reddit Add to Digg Add to Add to Google Add to Twitter Add to Stumble Upon
Add to Informational Site Network

Viewed 3561