CONSTRUCTION OF A PROGRAMMABLE CENTRIFUGE
In 1986, the company Sumy Machine-Building Shops was created from funds held by Sumy sugar-plant owners,
who had attracted Belgian capital and technology for the fabrication and repair of equipment for sugar plants.
Today, the company Sumskoe NPO im. M. V. Frunze is one of the largest establishments in Ukraine, which is fitted
out with modern metalworking equipment and computer facilities. The staff of the establishment is comprised of highly qualified specialists
The Sumskoe NPO im. M. V. Frunze is one of the largest producers of different types of industrial centrifuges, and
is constantly expanding the range of products and refining equipment for the sugar industry. The NPO supplies centrifuges,
evaporators with a mechanical circulator, dry-sugar agitators-crystallizers, beat-pulp presses, plants for the granulation of dry
beet pulp, water-packed ring vacuum pumps and compressors, juice pumps, etc.
Mastery of centrifuge production for the sugar industry was begun shortly after creation of Sumy Machine-Building
By the end of the 19th century, primarily vertical centrifuges with a lower belt drive were used in sugar plants. The
rotational speed of the rotor of this centrifuge was 700–800 rpm, its internal diameter was 760 or 910 mm, the dry-sugar
charge was approximately 150–180 kg, while the duration of the first-product dry-sugar spin cycle was approximately
5–7 min. Sugar was often produced with a high color index due to inadequate rotational speed. There was no mechanization
or automation of the spinning process.
Suspended centrifuges were improved during the period from 1940 through 1950. The manufacture of PM-1200 centrifuges,
which possess a rotor with an inside diameter of 1200 mm and rotational speed of 960 rpm, was mastered. The limiting
charge was 450 kg. A two-speed electric motor was used as a drive. The discharge of sugar, braking, and all remaining
stages of operation were, however, performed manually in this centrifuge.
High-speed centrifuges operating at a rotor turn rate of 1450 rpm were developed in the 1960s. The centrifuges were
fabricated with a mechanical device for off-loading the sugar, and a multiple-speed electric motor.
Continued refinement of these machines and experience accumulated with their manufacture and operation have
made it possible to develop new, more powerful and reliable automated FPN-1251T-01 and FPN-1251L-07 centrifuges with
first-product dry-sugar charges of 800 and 1000 kg, respectively, as well as a principally new design for the inertial continuous-batch
The advantage of a continuous-action centrifuge with an inertial discharge is the absence of any mechanical devices
for off-loading of sugar. Off-loading takes place under inertial centrifugal forces that exceed the frictional forces of the sugar
crystals on screens secured to the inner surface of the rotor, which has a certain taper angle.
Considering the necessity of mastering energy-saving procedures and equipment, specialists at Sumskoe NPO and
the GP KhMZ developed, fabricated, and tested the new FPN-1251L-08 centrifuge in 1998 (with a dry-sugar charge of
1000 kg per cycle) and an adjustable-frequency electric drive, as well as a centrifuge control system built by the union around
a programmable logic controller manufactured by the Schneider Electric Company (France).
A first-product high-sugar output of 20 tons/h was achieved on this centrifuge, and the specific electric energy consumption
per one ton of dry sugar was reduced by a factor of 2.5 as compared with series-produced centrifuges.
The FPN-1251L-08 centrifuge (Fig. 2) is a batch-action suspended filtering machine with bladed discharge of sediment,
and automated program control, which makes it possible to regulate from a desk the on-going output of operations
conducted in the production cycles; this permits optimal processing conditions for the product, depending on its quality.
Another two of these centrifuges were fabricated and placed in service for the Dubnosakhar company in 2000.
Based on operational results of these centrifuges under industrial conditions and suggestions of specialists at the
sugar plants, four of the new model FPN-1251L-09 centrifuges with a ring mechanism for the off-loading of sugar were fabricated
and delivered to the Valuyki Sugar Plant in 2001. These machines came complete with modern energy-saving
adjustable 110-kW electric drives and frequency converters manufactured by the Siemens AG Company (Germany), as well
as with automated control systems fabricated around a programmable logic controller developed by the Schneider Electric
Co. These electric drives demonstrated high reliability and made it possible to lower specific electric consumption per ton of 451