Porcelain was obtained in China in 620 and its way of manufacture was
kept in secret for many years. European porcelain was obtained much
later. In Belarus they have an old factory that keeps manufacturing
porcelain in spite of the fact its equipment needs to be replaced for
modern one. The process of porcelain manufacturing is very complex and
is shown below.
The history of porcelain started in 1883 when pottery industry was started in one of the streets of Belarus.
In 1920 the factory was owned by the
Minsk city council of workers and soldier’s deputy. The enterprise was
developed fast that time.
After Minsk was freed from the Nazi
occupants the factory had to be reconstructed. In 1946 it started
producing angular glazed and unglazed tiles.
A gas generator was exploited in 1950
making ceramic baking more successful. Qualitative changes of
technological processes lead to re-profiling of the factory that was now
busy with porcelain making. 15 March 1951 is the birthday of Belarus
The mechanized plant that had to produce 5,4 million pieces of cutlery was put into effect in 1979.
A block of additional works with the
area of 6000 square meters was put into effect in 1983. The factory
continued its development till 1990.
Today the following works are located on
the territory of the factory: hollow construction shop, flat
constructions shop, radioceramics shop, firebrick shop and laboratories.
The factory was closed in 2009. According to the official reason, it operated at a loss for many years.
Year of production 1977, item number 8, order number 2031210, mass 5157 kg (11370 ft).
Broken items are used in production of fresh molding material.
The raw material is taken to the factory
by car. Kaolin contains electrolytes and coagulants that can negatively
influence the quality of porcelain items. That is why it is cleaned and
goes through the stage of filtration.
Quartz sand is sifted, can be dried in case of high humidity and then loaded into a drum.
Flat constructions are formed in
submachines. They are cut into 20-25 pieces in one movement. Then the
item is put into an empty mould heading to the forming roller. The
steering circle rotates counterclockwise and stops every 90 degrees. The
mass is moved together with the mould and this is how an object is
The forming roller is heated to prevent adhesion of the mass. Flat and hollow items have different mould forms.
Complex objects such as sculpture, vases, etc. can be made by casting
only. The essence of the casting consists in the ability of gypsum to
dehydrate the suspension of porcelain mass.
Additional parts like handles are casted separately and then glued to
the body of the item. The details can be formed simultaneous with the
frame of the item.
After moulding the objects needs to get dried to carry out the following operations.
The first baking step is used to make the half-ready item strong and free from organic mixtures.
A porcelain semi-product acquires the necessary properties such as
mechanical strength, gas- and water tightness, thermal stability only
after glaze firing in high temperature.
During the large firing step temperature increases slowly. The final
firing temperature is 1340-1380 degrees Celsius (2444-2516 F).
Porcelain items are treated in furnaces for 27-35 hours.
Items in the furnace must be isolated from the free flame to avoid overburning.
Color glaze is one of the methods of item decoration.
The depth of the paint layer must not exceed 40 m to be well-fixed on the surface.
A drawing is coped through a tracing paper with a pencil. Then they
put the paper on a piece of cloth and make small holes along the
outlines so that the holes wouldn’t be located too close to one another.
The paper with small holes is straightened rubbing with pumice.
After that the tracing paper is put onto the porcelain item and
graphite is rubbed through the orifices. As soon as the paper is
removed, a pattern outline in the form of weak lines is left on the
In 1999 a group of German engineers visited the factory and found the
equipment old-fashioned. They also offered another modern project. But
the executives of the factory refused their offer.
Source ; www.izismile.com
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