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

Nickel
Nickel may be considered as the toughest among the non-rare a...

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

Tempering Colors On Carbon Steels
Opinions differ as to the temperature which is indicated by t...

Cyanide Bath For Tool Steels
All high-carbon tool steels are heated in a cyanide bath. Wi...

The Forging Of Steel
So much depends upon the forging of steel that this operation...

Fatigue Tests
It has been known for fifty years that a beam or rod would fa...

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

The Electric Process
The fourth method of manufacturing steel is by the electric f...

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

Separating The Work From The Compound
During the pulling of the heat, the pots are dumped upon a ca...

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

Crankshaft
The crankshaft was the most highly stressed part of the entir...

A Satisfactory Luting Mixture
A mixture of fireclay and sand will be found very satisfactor...

Preparing Parts For Local Case-hardening
At the works of the Dayton Engineering Laboratories Company, ...

Annealing In Bone
Steel and cast iron may both be annealed in granulated bone. ...

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

Carbon Tool Steel
Heat to a bright red, about 1,500 to 1,550 deg.F. Do not ham...

Refining The Grain
This is remedied by reheating the piece to a temperature slig...

Detrimental Elements
Sulphur and phosphorus are two elements known to be detrimen...

The Quenching Tank
The quenching tank is an important feature of apparatus in c...



Pyrometry And Pyrometers






Category: PYROMETRY AND PYROMETERS

A knowledge of the fundamental principles of pyrometry, or the
measurement of temperatures, is quite necessary for one engaged
in the heat treatment of steel. It is only by careful measurement
and control of the heating of steel that the full benefit of a
heat-treating operation is secured.

Before the advent of the thermo-couple, methods of temperature
measurement were very crude. The blacksmith depended on his eyes
to tell him when the proper temperature was reached, and of course
the color appeared different on light or dark days. Cherry
to one man was orange to another, and it was therefore almost
impossible to formulate any treatment which could be applied by
several men to secure the same results.

One of the early methods of measuring temperatures was the iron
ball method. In this method, an iron ball, to which a wire was
attached, was placed in the furnace and when it had reached the
temperature of the furnace, it was quickly removed by means of
the wire, and suspended in a can containing a known quantity of
water; the volume of water being such that the heat would not cause
it to boil. The rise in temperature of the water was measured by a
thermometer, and, knowing the heat capacity of the iron ball and
that of the water, the temperature of the ball, and therefore the
furnace, could be calculated. Usually a set of tables was prepared
to simplify the calculations. The iron ball, however, scaled, and
changed in weight with repeated use, making the determinations
less and less accurate. A copper ball was often used to decrease
this change, but even that was subject to error. This method is
still sometimes used, but for uniform results, a platinum ball,
which will not scale or change in weight, is necessary, and the
cost of this ball, together with the slowness of the method, have
rendered the practice obsolete, especially in view of modern
developments in accurate pyrometry.





Next: Pyrometers

Previous: Furnace Data



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 3441