Protection of industrial electrical machines from flooding in mines

mine workings. Dewatering plants ensure the safety of mining
operations. They prevent flooding of mine workings. Therefore,
electric dewatering pumps are considered an important type of
processing equipment in underground mines and mines. Industrial
electrical machines used in pumping and other installations are aircooled and cannot operate underwater. When such a unit is flooded,
water destroys the electrical part. The author’s ideas are implemented
in the design of an electric motor with a dynamic air cushion in an
electric cavity. Research is of particular value when used in offshore
subsea mining complexes. Full-scale experiments with asynchronous
motors for flooding depths of up to 100 meters, at appropriate air
cushion pressures, have been carried out. A simulation model has
been developed that allows one to determine the temperature regimes
of improved structures immersed at different depths. It has been
established that industrial electrical machines are capable of reliably
operating in watered mine workings and in shelf conditions at
considerable depths with minor design changes. However, in this
case, it is necessary to take into account the payload, rotation speed,
thermal conductivity and kinematic viscosity of air, which determine
the temperature portrait of an electric machine for different
immersion depths. The results obtained will help to make decisions
about permissible overloads or restrictions when operating electric
machines under water. Compliance with these recommendations will
preserve the life of electrical machines when flooded. Proposed are
substantiated design solutions of technical devices that ensure longterm operation of electric motors flooded in mine workings. These
solutions make it possible to increase the safety of work when
watering mine workings.