A new 4000 kW sugar shredder motor from MENZEL was recently acquired by one of the leading sugar factories in La Réunion. The six-pole slip ring induction motor available from stock was customized and is now driving a large sugar cane shredder.
The new shredder motor from our Berlin motor warehouse was converted from air cooling IC611 to IC 81W CACW water cooling exclusively at the request of the customer. This is rather untypical for a slip ring motor. The air-water cooling system is totally enclosed and works as a closed circuit for the internal cooling air. The cooling of the slip ring chamber itself is ensured by air-to-air cooling with a heat exchanger and external fans which are also readily available in our warehouse.
Slip ring induction motors being customized
A majority of the slip ring induction motors leaving our motor factory in Germany are custom-made or adapted to produce identical replicas of obsolete motors that are no longer produced by major manufacturers such as Siemens or ABB. Thanks to our unique, extensive motor inventory, we can also react very quickly in an emergency.
The new shredder motor for this sugar plant needed to be fully interchangeable 1:1 with an existing motor without having to make any further adjustments to the customer's shredder system or foundation. Menzel not only adapted the cooling type of the stocked motor. The motor shaft was also mechanically processed (reducing the diameter and length of the shaft end) and the foot mounting holes were re-drilled in a relatively short time in accordance with the customer‘s requirements. Before delivery, the rotor was rebalanced and the motor went through complete routine tests, including no-load test.
Performance data of slip ring induction motor
- Menzel motor type: MEBSSW710-06
- Motor standard: IEC / EN 60034-1
- Nominal power: 4000 kW (4 MW)
- Nominal voltage:5500 V
- Nominal frequency: 50 Hz
- Number of poles: 6 poles
- Nominal speed: 991 min-1
- Design: IM B3
- Frame Size / Shaft height: 710 mm
- Degree of protection: IP 55
- Cooling type: IC 81W water-cooled
- Weight: 19200 kg
Motors used in sugar mills
In the past, steam turbines were primarily used in sugar factories to drive large sugar cane shredders. Today it is asynchronous motors that move the huge loads involved in sugar production. Due to the shredder's high moment of inertia, the relatively long start-up times and the high demands on the start-up torque, three-phase slipring motors with liquid starters are today’s prime movers.
MENZEL three-phase asynchronous motors with slip ring rotors are available from 75 kW to 8000 kW. They are very robust and extremely resistant to dust, dirt or moisture, which is an advantage for application environments such as a sugar factory.
Sugar industry on La Réunion
The island of La Réunion in the Indian Ocean is covered with huge sugar cane plantations. The sugar cane industry is one of the most important export sectors and at the same time the island's first food industry. Mainly brown sugar, alcohol and starch are extracted from the raw material. The plant also serves as animal feed and it is used to generate electricity.
The sugar cane originally came from New Guinea and was brought to the island of Réunion in the 17th century. A sugar cane plant can grow up to five meters high. It is mainly grown in the eastern part of the island. The harvest takes place from July to December, when the sugar cane shredders run at full speed.
Slip-ring motors with high power density and compact design
Slip-ring motors are particularly suitable for heavy starts, especially on unstable power networks. They have a high power density and have a compact design thanks to the internal slip ring properties. The modular structure of our series enables a variety of cooling and protection types as well as various mounting options. The classic slip ring rotor may require a little more monitoring, but is a well proven, particularly reliable and easily maintained technology.
Menzel has been a manufacturer and supplier of large electric motors for industrial plants all over the world since 1927. Our slip ring motors are used in a wide variety of industries such as sugar, cement, paper, power, mining or steel . They are used to drive shredders, crushers, mills, compressors, fans, refiners, etc.
The optimum choice of electric motor depends on the individual application. Our customer focussed, experienced engineers would be happy to advise you!