DE74367C - Process for tempering iron objects without the use of annealing vessels - Google Patents

Description

IMPERIAL

PATENT OFFICE

PATENT LETTERING

CLASS 18: Ironmaking.

(Kingdom of Saxony).

Patented in the German Empire on May 11, 1893.

So far, the malleable cast has been made in such a way that which removes too much chemically bound carbon in the raw castings It was found that these cast pieces were placed in annealing vessels with tempering materials in the dry Condition packed and then annealed.

This process has the disadvantage that it is dry in the ground state Annealing vessels brought tempering material under the action of the glowing heat and its own weight of the wrapped castings settles and a significant crushing and bending respectively causes a more or less large deformation of the cast pieces on all sides, an inconvenience, the cumbersome and expensive straightening of the tempered cast conditional, whereby a considerable part of the cast pieces is broken up, and especially the stronger parts, which, for the necessary straightening, are heated to red heat have to lose softness and quality through cooling. The incandescent vessels are also quickly worn out by the sustained glowing heat and the acquisition costs are significant as a result elevated.

These deficiencies are eliminated by the new procedure. With the same the Tempering materials with the addition of milk and clay or other binding agents a pulp or mixed with a mortar-like mass, the cast pieces to be tempered in removable Wooden vessels packed and poured in layers with the pulp-shaped tempering compound, The whole vessel is dried until the contents form a solid whole, then the wooden walls deducted and the outer surfaces of the self-supporting forms with accordingly Thick layer of fire-resistant materials clad around the wrapped castings to protect the fire. With this new tempering process, the use Completely dispensable from annealing vessels, and secondly, the castings are made by storage Protected from any deformation in a solid, mortar-like, stable tempering compound.

Furthermore, the water added to the tempering material brings further essential advantages, in fact:

ι. When heated, the water escapes as steam through the tempering compound and makes it is very porous, which makes it much easier to unpack the tempered pieces of gas will;

2. the escaping warm vapors cause a strong oxidation of the used, already used tempering materials, whereby they temper more vigorously and the Gufs thereby gains in quality;

3. Ease the pore channels in the tempering compound formed by the escaping steam essentially the removal of the carbon oxide gases formed during the tempering process.

Even when annealing hard gray cast iron in order to make it soft, this new one can Procedure for the purpose of saving the annealing vessels and avoiding warping of the cast pieces can be used with the greatest success by making the castings in carbonaceous Materials, such as Kohllösche and so on, with the aforementioned binders in a paste-like state be wrapped, dried and annealed.

Claims (1)

Patent claim: Process for tempering iron cast goods, characterized in that the same in pulpy tempering materials mixed with binding agents (clay, lime or the like) are packed, after which the whole is dried, so that tempering vessels during tempering can be dispensed with, and warping of the castings is prevented.