Introduction to Rolling steel -Part 1

Liquid steel is usually cast in continuous casting machines in the shape of billets, blooms, or slabs. In some plants, it is also being cast in continuous casting machines in the shape of thin slabs or dog bone sections. These shapes are processed by hot rolling by passing them through plain or grooved cylindrical rotating rolls to produce plates, sheets, rods, structural sections, and tubes etc.

Rolling process is one of the most important and widely used industrial metal forming operations. It provides high production and close control of the final product. It was developed in late 1500s. It accounts for 90 % of all metals produced by metal working processes.

Rolling steel is a metal forming process in which steel is passed through a pair of rotating rolls for plastic deformation of the steel. Plastic deformation is caused by the compressive forces applied through the rotating rolls. High compressive stresses are as a result of the friction between the rolls and the steel stock surface. The steel material gets squeezed between the pair of rolls, as a result of which the thickness gets reduced and the length gets increased. Rolling is classified according to the temperature of the steel rolled. If the temperature of the steel is above its recrystallization temperature, then the process is termed as hot rolling. If the temperature of the steel is below its recrystallization temperature, the process is termed as cold rolling.

The rolls run on massive neck bearings mounted in housings of enormous strength and driven by powerful electric motors. These are known as mill stands. There are several types of rolling mill stands as given below.

• Two- high stand – It is the basic type of rolling mill stand in which two opposing rolls are used.

• Two-high pullover stand – The rolling steel stock is returned to the entrance for further reduction.

• Two-high stand, reversing – The work can be passed back and forth through the rolls by reversing their direction of rotation. 

• Three-high stand – It consists of three rolls. The upper and lower rolls are driven while the middle roll rotates by friction.This improves the productivity.

• Four-high stand – It has small diameter rolls (less strength and rigidity) are supported by larger-diameter backup rolls. Rolling power is directly proportional to roll diameter. 

• Universal mill stand – This stand has two horizontal rolls and two vertical rolls. Vertical rolls are used to control the width of the work simultaneously.

• Cluster mill or Sendzimir mill stand – In this rolling mill stand, each of the work rolls is supported by two backing rolls.

• Planetary mill – It consists of a pair of heavy backing rolls surrounded by a large number of planetary rolls. Each planetary roll gives an almost constant reduction to the slab as it sweeps out a circular path between the backing rolls and the slab. 

Fujian Putian Geili Machinery manufacturing Co., Ltd was founded in 2006, the registered capital of 20,000,000 yuan. The company is located in one of the city center onn the west side of the Straits Economic Zone, Xianyou Putian. As a professional and experience manufacturer in China, we can supply designing, manufacturing, installation and commissioning of the equipment with "turn-key" service.

 Two high Rolling mill

Useful application of roll forming machine

Rolling of metal sheet is the bending continually of the piece along a linear axis. This causes alteration of the original form of the sheet; it becomes deformed. The material receives progressive shaping and contouring as it passes through a pathway of rollers. This product, steel now in a thinner flat state, is part of our everyday life. From the outside metal of your car, to the roof above your head, its uses are varied. To get sheet metal to this state, roll forming takes place upon it. Different roll forming machines prepare this material for the different products it will comprise.

Steel rolling procedure:
Waste steel ----melting---- casting----mold unloading----sorting-----deliver to heating furnace----heating to 1150 degree to 1200 degree----- come out furnace----- rolling----- finished product ----packing---- sales

Task Accomplished by the Machine
Roll forming machines contain power driven bullet type rollers and the basic task accomplished by them is bending the metal sheets like creating corrugated steel sheets and plates among others. They can also roll double sheets in the time required by ordinary machines for rolling single sheets. One of the basic advantages of using the rolling machine is automating the process of rolling making it cost and energy efficient and thereby making great savings in the overhead.

Rolling Machine Components
Among the components used in the rolling machine are –
High power driven qualitative bullet rollers;
Chain and gear driven rollers,Double sheet rolling support stands, andEmergency shut off switches.
Each of the components has its own specific role in the process of building up efficient and high quality rolling machines.

Why Use Roll Forming Machine
These machines are usually deployed for fabricating rigid as well as high strength parts using different types of metals. It can be used for light metals like aluminum as well as strong metals like steel of half inch thick. Rolling machines are used to manufacture building components with metals, and other items like angles, studs, supports, C as well as U channels and the hat channels among others.

 Steel Rolling Production Line (turnkey service)

Packing of steel coils

The function of packaging is not simply only physical protection but also marketing, barrier protection, security, information, convenience and portion control. Packaging has become an integral part of manufacturing business today and therefore manufacturers have to make sure that they have the right machines that allow them to pack their goods in the right way to the market.

One of my old customer said that a steel coil mill made a very simple package of the goods, and when arrived, customer opened the package and found that the surface of coils are all wet, or even water droplets. This will affect the normal use of galvanized roll. It's really terrible. Below are some notes, according to my experience, I would like to share with everyone refer to the package of the galvanized rolls.

Packaging are divided into horizontal packaging and vertical packaging. The main difference lies in the vertical packaging with a wooden tray or iron under it, in order to make the reinforcement of coils in containers more solid. Of course, horizontal packing is also safety, because when loaded into containers, it will be reinforced by different ways. No matter horizontal or vertical, the packing of roll is same.
1. Water proofpaper
2. Steel layer
3. Straps
4. Tags/ Marks

Above all is the details for the packing, and sincerely hope it will be helpful. Indeed, whatever you choose the steel coil or steel sheet, these experiences above can be noticed, as long as you do the packaging services better, customers can satisfy with our steel products and steel prices better.

We engineer the design and supply of equipment for rolling mills on a world wide global basis. We have many strong partners world wide that have excellent manufacturing experience and capabilities for our products that give geili an incredible price advantage.

Steel Wire rod Packing Machine

Rolling mill machinery and machinery manufacturing

In metalworking, rolling is a metal forming process in which metal stock is passed through one or more pairs of rolls to reduce the thickness and to make the thickness uniform. and rolling mill is a kind of equipment which can realise a metal pressing process. It includes major equipment, auxiliary equipment, lifting and transport equipment and ancillary equipment.

The primary function of a rolling mill is to shape the metal being passed through the mill in some way, and many come with attachments and accessories which can be used for different types of tasks. Both hot and cold rolling mills are available for different metalworking applications.

A basic rolling mill is designed to produce sheet metal. The metal is passed between two tough cylinders numerous times, with the distance between the cylinders being decreased with each pass so that the metal becomes thinner and thinner.Rolling mills can also be used to produce wire. The wire may be square, octagonal, or otherwise shaped by its passage through the rolling mill.

 Short stress path rolling mill

Fujian Putian Geili Machinery manufacturing Co., Ltd was founded in 2006, the registered capital of 20,000,000 yuan. We have our own R&D department, which can develop and design products independently at the market’s price.Staffed with advanced and efficient technology and equipment, we are able to manufacture and assemble all the products independently, which ensures the good quality and JIT delivery.We engineer the design and supply of equipment for rolling mills on a world wide global basis. We have many strong partners world wide that have excellent manufacturing experience and capabilities for our products that give geili an incredible price advantage

Tandem Rolling Mills for Wire Rod