TINVO, found in 2007, is a company among the manufacturer, trader & technical service provider of hot and cold rolling mill rolls, steel making machinery & accessories. Our leading products are precisely engineered and fabricated from fine grade materials and advanced technology, some of them are procured from certified top-class partners. Our product range is inclusive of Hot & Cold Rolling Mill, Wire Rod/Rebar Rolling Mill, Strip Rolling Mill, Section rolling Mill, Straightening Machine, Drawing Machine, Flywheels, Cast Roll, Forged Steel Roll, Special Mill Roll, etc.
Mill Rolls
The mill rolls are mainly used for the rolling mill, which causes continuous plastic deformation of the metal. The roll is mainly composed of a roll body, a roll neck and a shaft head. The roll body is the middle part of the roll, which actually participates in the rolling of the metal with a smooth cylindrical or grooved surface. There are steel rolls, cast iron rolls, alloy rolls, ceramic rolls, etc, according to the roll material. Depending on the manufacturing method, the mill rolls have types of casting rolls, forging rolls, surfacing rolls, sleeve rolls, etc. Also, mill rolls are classified into hot rolling rolls and cold rolling rolls, as per the steel. The properties and quality of a roll generally depend on its chemical composition and manufacturing method and can be evaluated by its microstructure, physical and mechanical properties. The mill roll features resistance to thermal cracking, high hardness, impact resistance, strict finish requirements, etc.
Rolling Mill
Rolling mill is an equipment used for the rolling process of the metal and it can complete the entire process of rolling. There're mainly cold rolling mill, hot rolling mill, continuous casting machine, copper aluminium-zinc rolling mill, etc. The rolling mill mainly consists of unwinding machine, rolling system, driving system, hydraulic system, control system, roll removal device, etc. According to the product variety, the specifications, requirements for quality and output, select the type and size of the finished or semi-finished rolling mill. It can be equipped with transport auxiliaries, lifting and other auxiliary equipment. The development trend of the rolling mill is continuous, automated and professional with high quality and low consumption. The types of rolled products are constantly expanding. Some new rolling methods which are suitable for continuous casting and rolling as well as various special structures adapted to new product quality requirements and improving working efficiency are being developed.
Auxiliary Equipment For Rolling Mill
Auxiliary equipment refers to various machinery and equipment other than rolling mill. It consists of mechanical equipment used to complete a series of auxiliary processing procedures. According to the difference usages, auxiliary equipment can be classfied into the flying shear machine, drawing machine, straightening machine, cooling equipment, lifting and transporting equipment, etc. The selection of auxiliary equipment is very important for rolling mill. The equipment should meet the requirements for product production. It has high working efficiency and guarantees that the rolling mill saves rolling time with high output. The structure of the equipment should be advanced and reasonable with flexiblity in movement, easy to operate and maintain. The standardization of spare parts is necessary with easy manufacturing. The production capacity of the auxiliary equipment is generally greater than the rolling mill to ensure production capacity of the rolling mill. The equipment design is economical and reasonable with small in size and light in weight.
Φ200-650 hot rolling mill machine adopts a three-roll working base, used for rolling small steel bars. TINVO is your trustworthy manufacturer for hot rolling machine. The configuration of the machine is electric motor - gear reducer - gear housing - rolling mill. The rolling mill reducer is with a center distance of 600-700mm. Since the steering and rotational speed of the rolls are irreversible, the prime driven power applies a high-speed AC main motor with a lower cost. Considering that the rolling load is very uneven, a flywheel is added between the gear reducer and the motor in order to balance the motor load. The purpose of the gear housing is to transmit torque to the work roll. Three cylindrical herringbone gears of equal diameter are arranged in a row on the vertical plane of a closed box.
Φ200-350 rolling mill is the equipment of metal hot rolling mill process, which mainly refers to 2 hi roll reversible rolling mill and 3 hi roll reversible rolling mill. The working structure is composed of mill rolls, roll bearings, rolling mill guides, rack, rail seat, roll adjusting device, upper roll balancing device, and roll changing device.
Φ650 rolling mill is generally used as a cogging machine in the rolling mill production line. It is used to roll the slab introduced from the furnace to obtain the desired shape, size, texture and properties, for the lower mill to bite-in. Because the rolled parts just coming out from the heating furnace has the characteristics of high temperature, good plasticity, low deformation resistance, large the pressing amount of the cogging machine (generally up to 50%), the roll of rolling mill is large, and finally, the rolled product has good performance and no residual stress, no bubble, small crystal grain, dense inside texture.
Forged steel roll is a type of rolling mill rolls. The roll has a microstructure that allows the surface finish to be resistant to thermal shock and a hardness depth prevents from rehardening in subsequent applications.
Firstly, we give some basic knowledge about the forged steel roll including the definition, types, feature, chemical composition, etc.
What Are Forged Steel Roll
Forge steel roll provides a mill roller solution for rolling mill. It is one of the most wear parts during the rolling process. It is mainly made of forged steel. It is forged in hydraulic presses for high toughness and pureness, widely used in cold rolling mill, steckel mills and continuous hot strip mills. As different rolling mills have specific requirements and various rolling conditions, different alloy elements can be added into the steel for higher performance of the roll. The roll covers forged steel work roll or intermediate roll, forged steel back up roll.
Forged Steel Roll
Definition
The forged steel rolls are made from steel ingots by forging, which can solve metallurgical defects such as loose and shrinkage holes in the ingot, and crush the coarse cast structure to obtain superior quality roll with high resistance.
The production process includes smelting, ingot casting, forging, post-forging heat treatment, rough processing, final heat treatment and finishing.
Feature
High Toughness
Surface Hardness Uniformity
Fatigue Resistance
High Hardness And Durability
Application
It is mainly used as strip rolling mill working roll and backup roll and is a high speed roll (HSS roll) for tandem and reversing cold reduction mills.
Forged Steel Back Up Roll
The forged back up roll is a mill roll that supports the work roll and intermediate roll for the purpose of avoiding deflection of the work roll and affecting on the yield and quality of the plate and strip rolling mill. This is the key function of back up roll to ensure the operation of the whole rolling mill. The common materials are 9Cr2Mo, 86CrMoV7, 70Cr3Mo with 0.80% to 0.95% carbon content 2% Cr content. The diameter of roll body ranges from 350mm-1600mm.
Feature
High Rigidity
The back up roll requires high rigidity to ensure the smallest deformation for supporting work roll.
Good Fatigue Resistance And High Peeling Resistance
The backup roll always need to support work roll or intermediate roll. Overloadig cause the subcutaneous miccrocrack propagation and roll body peeling off. So the excellent fatigue resistance is necessary.
High Surface Hardness With Good Hardness Uniformity
Outstanding surface hardness ensures the exceptional wear resistance and can reduce the formation of concave roll shape.
Excellent Yield Strength And High Toughness
To guarantee the long service life, the deep hardened layer of roll body, good strength and toughness of roll neck and roll body and strong anti-accidents are required.
Application
Forged steel back up roll is applicable for 4-Hi mill, 6-Hi mill, and other some small mill
Forged Steel Work Roll
Definition
The forged steel work roll is solid-forged roll made of alloyed steel, close to eutectoid and hypereutectoid steel. It has a good combination with hardened surface which creates a strengthened working layer, heat check and tough core resistance to breakage. Heat treatment reduces and equalizes residual internal stress.
Feature
High Hardness
The high hardness and great depth of hardness are needed for cold reduction mills.
Increased Heat Resistance
With the strong heat resistance, the roll can be capable of retain high hardness with the roll under continuous and constant heating rate
No Metallurgical Flaws
High Resistance
It is also can ideal hardness and high resistance to spalling, surface flaws, cracks, scaling,etc.
No Microstructure Flaws
The surface microstructure consists of fine grain martensite and finely dispersed chromium carbides.
Application
Tandem mills
Reversing cold rolling mills
Temper mills
Forged Steel Rolls Used In Rolling Mills
Hot Rolling Mill
The forged steel rolls can be used for hot plate mill and these rolls have the features of rich in alignment, high toughness and strong wear ability.
They are made of forged steel blanks and can withstand the special heat treatment for excellent hardness.
Cold Rolling Mill
The back up roll and work roll can be used for cold rolling mill. The forged rolls are produced by steel-making, refining and forging. A homogenous highly dispersed structure provides mechanical properties of the internal layer for complicated heat treatment. It becomes easier for exceptional performance by using the forged rolls which are applied in cold rolling mill.
Summary
Forged steel roll is an important mill roll with its outstanding working performance. It can be used as work roll, back up roll and intermediate roll with its high hardness, superior yield strength and high resistance to spalling, fatigue, scaling, etc.
The cold rolling mill is a new type of cold-rolled steel processing equipment. The machine can process hot-rolled wire rods and hot-rolled coils with a diameter between 6.5 mm and 12 mm into cold-rolled ribbed steel bars with a diameter of 5 mm to 12 mm. It has types including 4hi cold rolling mill, 2 hi cold rolling mill, two-ribbed cold rolling mill, spiral blade cold rolling machine, flat steel cold rolling mill. It adopts an electric motor to drag the reinforcing bars and uses the load-bearing rolls, work rolls of the rolling mill to apply force on both sides of the reinforcing bars. The purpose of rolling cold-rolled ribbed bars with different diameters is achieved by changing the size of the gap between the two rolls. The equipment can simultaneously process the warp and weft directions of the base material during the cold rolling process. Under the premise of maintaining the relative balance and stability of the product in the center area of the original cross-section, improve the resistance and compression, still retaining sufficient elongation performance.
4hi Cold Rolling Mill
The 4hi mill is a kind of cold rolling processing machine. It is suitable for the cold rolling of carbon steel, alloy steel, copper, aluminum, etc. It has the characteristics of large rolling force, high precision and strong stability. The four high mill has automatic control function with the full hydraulic machine electricity integration. The machine can automatically balance and center, automatic thickness. It is immensely used to roll down aluminum sheets in different thickness. It is the most advanced in the field of non-ferrous metal cold rolling equipment.
2 Hi cold rolling mill
The 2 Hi cold rolling mill is a two-roller mill, used for the cold rolled of low-carbon steel, non-ferrous metal sheet and alloy powder cold-rolled strip. The machine consists of main motor, gear reducer, herringbone gear seat, universal joint shaft, working machine base, electric control cabinet, etc. The system adopts special rolling mill bearing and the roller material is 9Cr2Mo.
Two-ribbed Cold Rolling Mill
The cold rolling mill adopts two-rib forming and tempering technology. The appearance of the machine is black and blue and the thread is clear and plump. The yield strength and tension are better than ordinary cold-rolled ribs steel and Grade III steel. 500MPa high strength steel fully meet the requirements of the building requirements.
Spiral Blade Cold Rolling Machine
The cold rolling mill machine is mainly used to produce spiral blades of various specifications. The machine can squeeze the strips of different materials to a variety of sizes of continuous spiral blades through the relative movement of two conic rollers. It is equipped with a hydraulic cutting device for cutting arbitrary lengths as needed. Spiral vane cold rolling mill is automation equipment that integrates electrical, hydraulic and mechanical devices. It has high precision and stability. Helical vane cold rolling mill has the characteristics of variable frequency operation, compact structure and simple operation. The working speed of the cold rolling machine can be changed according to the actual situation. The helical vane cold mill eliminates the cumbersome and complicated processes.
Flat Steel Cold Rolling Mill
This cold mill is a new kind of cold rolling process equipment. The machine adopts a combination of flat rolling and vertical rolling. It can wind the rolling coil to flat steel of a certain specification. The production line is equipped with analog signal equipment to make the equipment run smoothly and keep the straightness of the product. The mill is equipped with a cold rolling water cooling system to extend the service life of the roller. The rolling mill can produce flat steel products of different sizes and is used in different fields. The Cold rolled ribbed steel bar has been used in buildings, bridges, storage racks, grain bins, car bodies, railway coaches, highway products, transmission towers, transmission poles, drainage facilities, various types of equipment and others.
The cold rolling mill is for sale at TINVO, superior quality and best price guaranteed.
Hot rolling and cold rolling are the two main processes for the most steel or steel plate making, which have great influences on the structure and properties of the steel. A better mill roll will bring more superior quality steel. Which one is better between the hot rolled steel and cold rolled steel? And what’re the differences and how to distinguish? These questions are always people being concerning.
Firstly, we introduce some information about the hot rolled steel and cold rolled steel
Hot Rolled Steel
Definition
Hot rolled steel is the finished product through directly processed on the steel mold in the steel furnace with exceptionally high temperatures, rolling with the hot mill roller which can make sure the dimensions of the steel sheet according to the requirements., then coiled and cooling. The main steel rolling type is hot rolling.
Advantages
Compact the steel structure and improve the mechanical properties.
Disadvantages
1.After hot rolling, delamination occurs, when the non-metallic inclusions in the steel are pressed into thin sheet. Delamination greatly deteriorates the tensile properties of the steel.
2. Residual Stress caused by uneven cooling. Residual stress is an internal self-phase equilibrium stress without external force. Hot rolled steel may have negative effects on deformation, stability, fatigue resistance, etc.
Cold Rolled Steel
Definition
The cold rolled steel bar is obtained by cold working of the hot-rolled steel, such as cold drawing and stretching at a normal temperature. Cold rolling is often used for the production of small sections and steel sheets.
Advantages
Cold rolled steel bar has fast forming speed and high output. It can be made into a variety of cross-sectional forms to meet the requirements of the different use conditions. Cold rolling can make the steel have a large plastic deformation.
Disadvantages
Torsion is prone to occur under bending. Bending and torsional buckling is easy to occur under compression. So the torsional performance of cold rolled steel is poor, and the ability to withstand concentrated loads is weak.
How to Distinguish Hot Rolled Steel From Cold Rolled Steel
1. Carbon Content
The carbon content of hot-rolled steel can be slightly higher than that of cold-rolled steel. The density is the same when there are little differences in the components
2.Density
The density and composition of hot rolled steel can be checked through looking for various steel to find the specific one.
Cold rolled steel has high hardness and relatively has difficult for processing, but it is not easy to deform and has high strength.3. Production Process
The production process of hot-rolled steel and cold-rolled steel is different. Hot rolling steel is rolled at high temperature and cold rolling steel is processed from hot rolled steel at normal temperature. Generally speaking, cold rolled steel has better strength and hot rolled steel has better ductility.
What Are The Differences Between Hot Rolled Steel And Cold Rolled Steel
1.The Surface
The cold steel plate is cold rolled and the surface has no oxide scale with good quality. The hot steel plate uses hot rolled processing technique with oxide scale on the surface.
2. Toughness & Stretchability
Hot rolled steel has poor toughness and the price is low, while cold rolled steel has good stretchability and toughness, but the price is more expensive.
3.Mechanical Properties
The cold rolled steel has much better mechanical properties than hot rolled steel.
4. Formability
Since the surface of cold rolled steel is better than hot rolled one, the forming effect also better than that of hot rolled steel.
5. Torsion resistance
Hot rolled steel has higher free torsional stiffness than cold-rolled steel, so the torsional properties of hot-rolled steel are better.
6. Smoothness
The smoothness of cold rolled steel sheet is better than that of hot rolled sheet.
The article tells the simplified explanation of the two types of steel or steel plate. For more professional knowledge, please visit the website of hrbtinvo.com.