Overview of Cement ball mill

A cement ball mill is the equipment used to grind the hard, nodular clinker from the cement kiln into the fine grey powder. Most cement is currently ground in ball mills and also vertical roller mills which are more effective than ball mills. Cement crusher is applied for cement crushing. In cement production line you need to choose suitable raw material mill and cement crusher.

Ball mill is the key equipment for grinding after crushing process, which is widely used in manufacture industries of cement, silicate, new building material, refractory material, fertilizer, ferrous metal, nonferrous metal and glass ceramics. It can be used for dry and wet grinding of all kinds of ores and other grind-able materials.
Cement grinding mill and cement crusher play a very important role in cement making plant, which can crush or grind the cement into required fineness for industry application. Hongke cement mills have been honored as famous brand of China machinery industry, national top brand product, fixed-point production of national building materials, etc.

Characteristics of Hongke Cement Ball Mill

Cement ball mill has the characteristics of high adaptability to material, continuous production and being easy to adjust fineness of powder grinding. There are dry process production and wet process production process for cement ball mill. It also can be operated with grinding and drying process.

Ball Mills working Principle

A Ball mill is a horizontal cylinder partly filled with steel balls (or occasionally other shapes) that rotates on its axis, imparting a tumbling and cascading action to the balls. Material fed through the mill is crushed by impact and ground by attrition between the balls. The grinding media are usually made of high-chromium steel. The smaller grades are occasionally cylindrical rather than spherical. There exists a speed of rotation at which the contents of the mill would simply ride over the roof of the mill due to centrifugal action. Ball mills are normally operated at around 75% of critical speed, so a mill with diameter 5 m will turn at around 14 rpm.

The ball mill is usually divided into at least two chambers, (Depends upon feed input size presently mill installed with Roller Press are mostly single chambered), allowing the use of different sizes of grinding media. Large balls are used at the inlet, to crush clinker nodules (which can be over 25 mm in diameter). Ball diameter here is in the range 60–80 mm. In a two-chamber mill, the media in the second chamber are typically in the range 15–40 mm, although media down to 5 mm are sometimes encountered. As a general rule, the size of media has to match the size of material being ground: large media can’t produce the ultra-fine particles required in the finished cement, but small media can’t break large clinker particles. Mills with as many as four chambers, allowing a tight segregation of media sizes, were once used, but this is now becoming rare. Alternatives to multi-chamber mills are:

• Pairs of mills, run in tandem, charged with different-sized media.
• Use of alternative technology (see Roll-presses below) to crush the clinker prior to fine-grinding in a ball mill.

A current of air is passed through the mill. This helps keep the mill cool, and sweeps out evaporated moisture which would otherwise cause hydration and disrupt material flow. The dusty exhaust air is cleaned, usually with bag filters.

Product specification (m)	Milling form	Transmission form	Gear box		Motor power (kw)	Production capacity (t/h)	Total weight (t)
			Model	Speed reduction ratio
Φ1.83×7	Open flow	Brim	ZD60	4.5	245	6.5-8	43.8
Φ2.2×7.5	Circle flow	Brim	ZD70	5	380	8-10	64.8
Φ2.2×11	Open flow	Central shaft	D110	35.5	630	12-13	104.6
Φ2.2×13	Open flow	Central shaft	D110	35.5	630	16-18	114
Φ2.4×13	Open flow	Central shaft	D110	35.5	800	20-23	130.6
Φ2.6×13	Open flow	Central shaft	MFY100	19.5	1000	28-32	158
Φ3×9	Circle flow	Brim	D125	41.2	1000	28-36.5	167
Φ3×11	Circle flow	Central shaft	D140	42.8	1250	36-47	180
Φ3.2×13	Open flow	Central shaft	D140	36.5	1600	45-50	225
Φ3.5×13	Circle flow	Brim	JDX1000	5.84	2000	60-65	275
Φ3.8×13	Open flow	Central shaft	MFY250	16.5	2500	60-62	320
Φ4.2×13	Open flow	Central shaft	JQS3550	15.6	3530	85-87	380
Φ4.6×14	Circle flow	Central shaft	JSI160-C	14.6	4200	120-135	485