Introduction
     Type 1215-6Hl178 deepwell waGer-submersible three-phase  asynchronous motors are
manufactured according to the advanced manufacturing technology newly introduced from
Ritz Co,West Germany. In order to lift underground water for farm irrigation as well
as for city and industrial water supply, these motors are fully submerged in water for
prolonged operations  to directly drive deepwell pumps.  Its features are outstandingly
high-efflciency and exceptionally long service-life.

CONSTRUCTION
    Type 1215-1228 are of medium and small capacity waterfilled,sealed constraetion,water-submersible, threephase asynchronous  motors.
      Typically the motor is comprised of stator, rotor, thrust bearing,  guide bearings, compensation  bag and seals~ Stator windings are wound with especiallyinsultated water-resistant winding wire which ensures extremely high dielectric strength and heat resistance. Rotor is of squirrel-cage type. Thrust bearing and  guide bearings  are  made  of  extra-strong  and wear-resistant material, suitable for water lubrication. The thrust bearing is of special construction,thus the capability of taking pump axial thrust is greatly strengthened. An excellent sealing  device  is  installed at  the shaft  extention  side to prevent the entrance of well water into the motor. An elastic rubber bag is installed at the bottom to equalize the motor's internal water contraction/expansion pressure with the well water  submergence  pressure.
       Type 1234 motors are of larger capacity submersible motors. In order to increase the ability of heat-dissipation,pipe lines are welded on the motor housing.The motor's internal cooling water circulates through the pipe lines, and the well water outside of the housing carries away the heat.

       Type 6Hl157--6Hl178 are of high-voltage, large  capacity  submersible motors. Its  construction and materials used are similar to those of type 1234,but with even higher requirements.
 The motor's internal cooling water circulates through a small impeller installed at the rotor's bottom end and then it goes upward through the gap to the endsof stator coils and finally returns to the pipe lines at the bottom end of the motor. For 6Hl166 type motors, cooling water will even circulate to the lower part of the pump. Its cooling ability is greatly increased.
Stator coils are wound with a special kind of insulated'water-'resistant winding wire. The thrust bearing and guide bearingsare made of top grade carbon and will take excessive axial thrust. In order to increase its cooling ability a shroud shouldbe added to the unit when used for mine drainage. As these high voltage,large capacity  motors  are carefully built, out-Standing performance and longer service-life can be ensured.