Basic Information

Product Description

Modular Slip-Ring Motors, Type NMK

Availability for Heavy Load Inertia Applications
Slip-ring motors are an ideal solution for applications requiring high starting torque and low starting current. They are especially suitable for heavy load inertia applications, such as mill drives, or situations where network conditions are weak.

NMK slip-ring motors minimize mechanical stress during starting, thereby increasing the lifetime of your driven equipment. They provide maximized availability and high torque over the entire speed range.

Wide Range of Applications
These motors are widely used in mills, crushers, fans, and conveyors in the mining, cement, and metal industries. Additionally, they offer a reliable solution for pumps in the water industry, as well as safe area pumps, compressors, and mixers in the petrochemical industry.

Design & Customization
NMK slip-ring motors are available in shaft heights from 400 to 710 mm, with standard cooling methods and protection types of IC611/IP55 and IC81W/IP55. The motors are rated up to 10,000 kW.

The NMK motors feature a welded steel frame. The slip ring unit can be supplied with permanent contact brushes or with brush lifting gear. In both cases, the slip rings are enclosed in a housing located at the N-end, separated from the main motor frame. A Liquid Resistance Starter (LRS) is available upon request.

Note: While this catalog highlights typical technical data for 6kV and 11kV at 50 Hz for 4, 6, and 8 pole motors, the complete product scope covers motors with 60Hz, pole numbers up to 16, and voltage ratings up to 13.8kV. For more detailed technical data and configuration solutions, please contact us.

Mounting Arrangements

Standard mounting arrangements for NMK motors include:

• Code I: IM B3
• Code II: IM 1001 (Horizontal foot mounted)
• Other mountings, such as IM1002, are available upon request.

Enclosure and Cooling

Standard combinations for NMK motors are IC611/IP55 and IC81W/IP55. Other cooling methods, such as IC616 and IC86W, are available upon request.

IC611 / IP55
This design features an air-to-air heat exchanger mounted on the motor, which is fully enclosed. Shaft-mounted fans are fitted both inside the motor frame and inside the slip ring housing, as well as outside the casing to supply the inside and outside cooling circuits respectively. The motor is protected against dust and splashing water from any direction.

IC81W / IP55
The machine is totally enclosed and equipped with machine-mounted and SRU (Slip Ring Unit) housing-mounted air-to-water heat exchangers. A shaft-mounted fan is fitted inside the casing to supply the internal cooling circuit. The motor is protected against dust and splashing water from any direction.

Packaging

• Standard seaworthy package for export.
• Plywood package or wooden fumigation package.
• Suitable for long-distance transportation by sea or land.

Warranty Period

• Standard Warranty: 12 months after commissioning, or 18 months after delivery, whichever comes first.
• Extended Warranty: Available upon request. Please contact us for more details.