NT-LM SERIES VERTICAL MILL
Introduction
The NT-LM Series Vertical Grinding Mill is an advanced integrated grinding system developed by Henan Innovative Industry based on more than a decade of R&D experience combined with the introduction of leading international grinding technology. The NT-LM Vertical Mill integrates drying, grinding, powder classification, and material conveying into a single compact system, replacing multiple standalone machines with one highly efficient production unit.
The NT-LM Series was developed specifically to address the key limitations of conventional grinding equipment: low output capacity, high energy consumption, high maintenance costs, and large installation footprint. It has become the mainstream grinding solution in the powder processing industry across coal, cement, slag, and non-metallic mineral processing sectors.
Key performance advantages over conventional grinding systems include high grinding efficiency, significantly lower power consumption, larger acceptable feed size, adjustable output fineness, simplified process flow, compact space requirements, lower noise levels, minimal dust emissions, easy maintenance access, lower overall operating costs, and extended wear part service life.
APPLICATION RANGE
The NT-LM Vertical Mill is widely used across power generation, metallurgy, cement, chemical, and non-metallic mineral processing industries. It is suitable for grinding a broad range of materials from wet to dry, hard to soft, and coarse to fine.
01.
By Material Moisture:
From high-moisture materials of 20 to 30% humidity such as carbide, lignite, and chalk, through to ultra-low moisture materials below 1% humidity such as cement clinker.
02.
By Material Hardness:
From high-hardness materials such as quartz sand, steel slag, mining slag, pyrophyllite, and iron ore, through to low-hardness materials such as gypsum and calcite.
03.
By Output Fineness:
From coarse outputs of 2 to 5 mm such as raw shale for new wall material bricks and construction sand, through to ultra-fine outputs of 15 microns with 97% passing, for paper, chemical, and calcium carbonate applications. Output fineness is adjustable and easy to control during operation.
NT-SERIES VERTICAL GRINDING MILL STRUCTURE
The NT-LM Vertical Mill system consists of the following integrated components: main mill unit, quantitative feeder, classifier, high-pressure blower, connecting pipes and hoppers, electrical control system, and dust collecting system.
The mill body integrates the grinding rollers, grinding table, pressurization device, and internal classifier in a single compact vertical unit. The complete system footprint is approximately 50% less than an equivalent capacity ball mill system, making it suitable for installation in facilities with limited floor space or where open-area installation is preferred to reduce construction costs.
THE ANATOMY OF NT-LM VERTICAL GRINDING MILL
The NT-LM Series uses a modular pressurization device design that allows the mill to be configured with different numbers of grinding rollers to match required production capacity. As production capacity requirements increase, additional rollers are added using the same standard module components, allowing different capacity machines to be built from a minimum set of standardized parts.
The NT-LM Series is available in the following roller configurations:
Two Rollers Vertical Mill
Two Roller Configuration – Suitable for smaller production capacity requirements
Three Rollers Vertical Mill
Three Roller Configuration – Standard configuration for medium production capacity
Four Rollers Vertical Mill
Four Roller Configuration – For high production capacity requirements
Six Rollers Vertical Mill
Six Roller Configuration – Maximum capacity configuration for large-scale production
Working Principle
The drive motor powers the reducer, which rotates the grinding table. Feed material is delivered to the center of the rotating grinding table by the quantitative feeder. Under centrifugal force, the material moves outward toward the edges of the grinding table where it passes under the grinding rollers. The material is ground through a combination of roller pressure, grinding action, and cutting forces as it passes between the rollers and the grinding table surface.
Simultaneously, hot air is introduced around the base of the mill and flows upward through the grinding zone. This hot airstream carries ground material upward while also drying high-moisture feed materials during the grinding process. Coarse particles that are too heavy to be carried by the airstream fall back down to the grinding table for reprocessing.
Fine particles carried upward with the airstream enter the internal classifier. Particles meeting the required fineness specification pass through the classifier and exit the mill with the airstream, proceeding to the dust collection system where finished powder is separated and collected. Oversized particles rejected by the classifier are returned by the classifier blades to the grinding table for further grinding, completing the continuous closed-circuit grinding cycle.
Flow Chart
The NT-LM Vertical Mill system is available in two dust collector configurations depending on the application and material being processed:
Double-stage dust collector system
Normally used for grinding cement raw materials
In this configuration a cyclone collector is used for primary product collection, reducing the working negative pressure and air volume load on the secondary bag dust collector. This system maximizes collection efficiency for high-volume cement raw material grinding operations.
Single-stage dust collector system 1
Normally used for coal grinding in cement and metallurgical industries.
This configuration uses an explosion-proof bag dust collector with air flowing directly from the mill into the collector, reducing equipment quantity and simplifying system configuration for coal grinding applications.
Single-stage dust collector system 2
Normally used for grinding cement clinker, mining slag, steel slag, and non-metallic minerals.
This configuration uses a high-density electrostatic precipitator or bag dust collector with air flowing directly from the mill, reducing equipment quantity while maintaining high collection efficiency for dense mineral grinding applications.
TECHNICAL ADVANTAGES AND FEATURES
01.
High Efficiency with 40 to 50% Lower Power Consumption Than Ball Mills
The NT-LM Vertical Mill delivers significantly higher grinding efficiency than ball mill systems, consuming 40 to 50% less power for equivalent output. Its high production capacity and ability to operate during off-peak power periods further reduce energy costs across continuous production operations.
02.
Full PLC Automation with Remote Control Capability
The complete automatic PLC control system supports remote monitoring and control, simplifying operation and reducing labor requirements. Easy operation and maintenance access reduces the technical skill requirements for daily operation and routine maintenance tasks.
03.
Integrated System Reduces Investment and Space Requirements by 50%
By combining crushing, drying, grinding, and conveying in a single integrated unit, the NT-LM eliminates the need for multiple standalone machines. The compact system layout occupies approximately 50% less floor space than an equivalent ball mill system and can be installed in open areas, significantly reducing civil construction costs and total project investment.
04.
Sealed Negative Pressure Operation with Low Vibration and Noise
The complete grinding system operates under negative pressure with full sealing, eliminating air leakage and workshop dust pollution. Low vibration and noise levels make the NT-LM one of the most environmentally compliant grinding solutions in the powder processing industry. The vertical mill is the preferred equipment for reducing power consumption across China’s powder processing industry.
05.
Roller Height Control Prevents Vibration from Empty Mill Operation
The roller height-controlled device prevents the strong vibration caused by insufficient material in the grinding zone. The redesigned roller sealing system eliminates the need for a sealing blower and reduces oxygen content inside the mill, preventing the risk of explosion in coal grinding applications.
06.
Easy Maintenance Access and Extended Wear Part Service Life
The hydraulic roller extraction device allows rollers to be pulled out of the mill without removing other components, providing large and accessible working space for maintenance and spare part replacement. Both left and right sides of the roller cover are usable, effectively doubling wear part service life. The mill can be started without feed material, eliminating difficult restart procedures. The roller and grinding plate are manufactured from specialist wear-resistant materials for extended service life.
07.
Stable and Consistent Output Powder Quality
The short material residence time inside the mill makes powder fineness testing and composition analysis easy and responsive. Output powder has well-distributed particle shape, narrow particle size distribution, and good fluidity, suitable for a wide range of downstream applications. The mechanical iron content in the output powder is low and easily removed, resulting in higher whiteness and purity when grinding white or transparent materials such as calcium carbonate and kaolin.
SPECIFICATION DATA
Three specification data sheets are provided covering NT-LM Raw Material Vertical Mill, NT-LM Cement Vertical Mill, and NT-LM Slag and Steel Slag Vertical Mill configurations. Final equipment selection and specification is determined based on your specific material Bond Index, required output fineness, and production capacity requirements.
Note: Raw Materials Bond Index ≤13kwh/t
Specification and Technical Parameter Sheet of NT-LM Cement Vertical Mill
Note: Raw Materials Bond Index ≤18kwh/t
Specification and Technical Parameter Sheet of NT-LM Cement Vertical Mill
Note: Mining slag bond Index ≤25kwh/t: Steel slag bond index ≤30kwh/t; the output will decrease by 30%-40% grinding steel slag micro powder.
Looking for a Vertical Grinding Mill for Your Operation?
Tell us your material type, required output fineness, production capacity, and moisture content. Our engineering team will recommend the right NT-LM Series Vertical Mill configuration for your operation.