Ningguo Sifang Steel Ball Mold & Equipment Co.,Ltd

Brief introduction

The hot rolled steel ball is the steel ball formed by hot rolling round steel with the hot extrusion times of above 10 times produced by large steel works, which is controlled automatically in the whole process with uniform steel ball hardness, higher core hardness, low crashed rate and big impact value of steel ball. The performance of steel ball has difference according to different material of raw materials adopted. The hot rolled steel ball is produced with the production line of skew rolling, of which not only the production efficiency is high but also the wear resistance increases successively and quality is stable due to the rapid rise of introduction of new materials and new technologies in recent years.

Composition for main equipment in the production line of rolled steel ball

1. Storage rack and conveying device of automatic renewal of material

2. Induction heating furnace and temperature control device

3. Skew rolling machine of steel ball

4. Hoisting, conveying and cooling device of steel ball

5. Device of isothermal quenching

6. Car-type or on-line mesh-belt tempering furnace

7. Automatic control system of quenching temperature, water discharging

after quenching and tempering temperature

Production process

Rolling ball production line main production process

1. Carry out detection assay of texture and diameter to the raw material after being out into plant.

2. Steel ball blank is heated up to proper temperature in the induction heating furnace before rolling.

3. Red-heat billet rotates forwards between 2 special spiral-hole rollers and is continuously rolled into steel ball after being sent into ball rolling mill. Each set of ball rolling mill can be rolled into 40～120 steel balls per minute.

4. The rolled red-heat steel ball is immediately put into online heat treatment installation for quenching when it is cooled to hardening heat, after quenching, it is cooled to proper temperature (50℃ below), and then put into online continuous tempering furnace for destressing tempering, so as to make steel ball obtaining high and even hardness.

5. The qualified products after inspection are delivered to finished goods warehouse for customers after being packaged.

Ball rolling mill

Such rolling mill has simple operation and convenient adjustment, cast steel rack is used to solve the problem that welded machine needs frequent adjustment in the operating process due to temperature distortion. Forging technology is applied in roll mandrel to make it greatly improving fatigue resistance, counter bending and fracture resistance. The way of circulating oil injection by filling pump is adopted in the bearing seat of pinion stand to avoid hard wear of bearing. When different specifications of steel ball are rolled in a same production line, variable frequency motor is used for controlling, which effectively utilizes the motor power to improve the output of steel ball.

Rolling principle and process description of steel ball:

Steel ball skew-rolling mill is used for producing steel ball. When skew rolling is implemented to steel ball, in order to make spiral direction of roller and spiral direction of rolled piece corresponding, axis of roller and the axis of rolled piece form an included angle, the included angle of two roller is generally 2°～6°, as shown in figure I, there is spiral hole in the roller, when the two rollers rotate homonymously, round bar blank rotates opposite to the roller and moves forward, under the action of spiral hole, round steel gradually becomes ball, the connecting neck parts of the balls are thinner and thinner, and finally, break to obtain steel ball.

Figure 1

Main technical parameters of ball rolling mill:

Through full research and transformation of our company to the rolled production line of the steel ball, and combined with the demands of home and abroad steel ball markets, develop the new-generation steel ball rolled production line, and develop the φ20mm-φ125mm series of complete equipment from heating, rolling to thermal treatment, used for producing various kinds of steel ball with the diameter from φ20mm-φ125mm.

Through multiple creative designs, the steel ball rolling line has the following properties:

1. Automatic loading control, improve degree of automation and reduce labour intensity;

2. Apply induction heating, environmental protection and free contamination, temperature uniformity and high production efficiency;

3. Cast steel semi-closed rack is applied in rolling mill to possess good stand stiffness and free from deformation;

4. Rolling mill is provided with electric lateral pressure adjusting device, simple adjustment and easy to use.

5. Automatic control of steel ball heat treatment quenching and tempering temperature to ensure quenching and tempering quality;

6. The produced steel ball has fine appearance, high hardness and low breakage rate.

The steel ball produced by the steel ball rolling equipment in our company has accurate size, rounding geometrical shape, high hardness, good mechanical property, and it has excellent properties of wear resistance, do deformation and no cracking. Its characteristics are as shown below:

a. High global hardness: surface hardness can be up to 57HRC-67HRC, volume hardness is up to 56HRC-64HRC and hardness gradient is evenly distributed;

b. High impact toughness: impact toughness is more than 12J/cm;

c. Low breakage rate: peeling resistance and crushing resistance are 10 times above than the general casting-forging steel ball, the frequency of Falling Ball Impact is above 20000 times, actual breakage rate does not exceeds 1%, close to zero crushing.

The rolling steel ball production line researched, designed and manufactured by our company is the full-auto assembly line work, it is up to the latest level of hot-rolled steel ball production.

Pictures of skew rolling units for rolling various types of steel balls

30mm steel ball skew rolling unit	40mm steel ball skew rolling unit
50mm steel ball skew rolling unit	60mm steel ball skew rolling unit
80mm steel ball skew rolling unit	100mm steel ball skew rolling unit

Data reference table for rolling steel ball

The common chemical components of billet for rolling steel ball

Rolled steel forging and finished product of steel forging

Application site of production line of various types of roll-forging steel balls

30mm, 40mm, 50mm steel ball rolling production line

60mm, 80mm, 100mm steel ball rolling production line

Equipment manufacturing, installation and commissioning:

Engineer available to provide paid service overseas

Field provide debugging, installation guide and technical consulting services and training

After-sales service:

1. Equipment guarantee period one year（Except wearing parts and artificial damage）, improper use by the buyer causes equipment problems, the seller only charges material cost of maintenance.

2. Our company strictly according to the specification to provide pre-sale, sale, after-sales service:

Pre-sale proceed project feasibility analysis, production site, equipment planning and matching;

In sale guide the customer production technology, technical requirements and equipment operation training, etc;

After sale provide the equipment maintenance, troubleshooting, process improvement, equipment upgrades, etc.

3. When our company equipment product updates, free upgrade service for the customer technical support.

http://www.steelballmold.com/