Domestic Development for Ultra-fine Grinding Equipment With the development of non-metallic industrial revolution, nano- materials technology has been widely used. The ultrafine grinding equipment also has a rapid development, such as  jet mill, vibration mill, impact mill, ultrafine ball mill etc.. Their have unique grinding principle, but the common defect is large power consumption.  With research the above equipment, our R & D personnel develop a new patented mill: GK990 ultrafine grinding mill, which Not only absorb the advantages of the above equipment , but also overcome its shortcomings. With impact , crush, grind joint crushing principle , so that the material is fully and completely crushed.

~1, Applications
GK9920,GK990 Series superfine pulverizer is mainly used in metallurgy, chemical industry, construction, pharmaceuticals, ceramics, electronics, military and other industries. For deep processing non-flammable, non-explosive mineral materials whose  Mohs hardness and humidity is under 9 and 6% respectively, such as Talc, feldspar, zeolite, Calcite, barite, pyrophyllite, dolomite, Phosphate rock, wollastonite, coal, kaolin, bentonite, bauxite, titanium dioxide, ferrosilicon, gypsum, mica, quartz, corundum, zircon sand, emery and so on.

2, Superiority
1. Unique grinding way: The rollers are hanged parallelly with the ring inside main frame.In the running process,roller assemblies stay still ,and ring rotates along with the tray.Materials are thrown around ring wall by centrifugal force and are propelled by shovel blade to the space between rollers and the ring.Meanwhile,the rollers revolve around roller shaft.The rotation is driven by the material which is between the ring and roller.Consequently ,material will be grinded by pre-tightening force from high pressure spring.
 
2. Lower Iron Content & Keep Material Color: There is no touch between roller and ring, so the iron content will be lower and material color will be keep better.
3. Lower Maintenance Cost: The maintenance cost for the main wearing parts ,i.e. roller, ring, shovel knife, is lower than Raymond mill.
4. Strong Grinding Force: The grinding force for each roller assembly , which comes from the spring force, can achieve 4000KG.
5.Super-fine Product: The fineness can be 600-1500 meshes.
6. Simple operation & Easy Maintenance.

3,  Main Structure and Working Principle

Main structure:

GK9920&GK990 SERIES SUPERFINE GRINDING MILL SYSTEM consists of vibrating feeder, main frame, air blower, super-fine classifier, cyclone collector, bag dust collector, electrical control device and pipe system. Besides, the jaw crusher , hammer crusher and bucket elevator will be assorted according to customer’s requirement.
The main frame is composed of lower case, cylinder cover, roller device, suspension device, tray, spring rod device and reducer.

Working Principle:

1,Grinding Powder: The material will be evenly and continuously delivered into main frame by vibrating feeder. Meanwhile, the material will be thrown around the grinding ring by centrifugal force and get between roller and ring by shove blade. The revolution of ring will revoke roller to rotate by the material movement. Consequently the material between roller and ring will be grinded by two high-pressure spring preload force.
2,Powder Filter and Collecting: The high-pressure airflow, aroused by closed cyclical supply system, mixed with grinded powder , will become a high concentration of air and go into super-fine classifier to filter. The qualified powder will be collected in cyclone and the bigger powder get back to be grinded again. The powder in cyclone collector is the final product.
3, Treatment of Excess Air: The excess air flowing into from pipe flange and feed inlet must be be promptly discharged, as the airflow will affect the cyclone collecting efficiency. The airflow can be exhausted when dedusting bag collector.

4, Technical Specifications

Technical Specifications
Model GK9920 GK990
Roller diameter(mm) 365 320
Roller length(mm) 200 160
Roller Qty(pcs) 4 3
Roller inner diameter(mm) 1250 960
Central Shaft Speed(r/min) 115 130
Classifier Motor Shaft Speed(r/min) 0-50HZ(0-1250) 0-50HZ(0-1250)
Blast Volume of Air  Blower(m3/h) 50000 24000
Wind Pressure of Air Blower(pa) 48000 23000
Max feeding Size(mm) 10 10
Product Fineness  600-1500mesh 600-1500mesh
Motor Specification
Model GK9920 GK990
Main Frame 55 37
Air Blower 55 37
Classifier 18.5 15
Whole Grinding Mill System Specifications
Overall Dimension after Assemblage(L*W*H)(MM) 5730*7070*9270 900*6500*7700
Gross Power(Kw)(excluding bucket elevator and jaw crusher) 128.5 89
Gross Weight(t) 27 17