What are the Failures of the Rolling Mill in Slitting Rolling?

What are the Failures of the Rolling Mill in Slitting Rolling?

In the slitting rolling of the rolling mill process, various bad phenomena often occur because of the misoperation, which directly affects the quality of the whole piece. Therefore, the corresponding preventive measures should be taken before rolling to ensure that the quality of the tied parts produced is the best.

During the whole rolling process, when the fastener leaks out in the high-temperature zone, it is very prone to burr. If it is in contact with the fastener or the temperature rises too fast, there will be the defect of sticking steel. At this time, if the tie piece and its contact, then there will certainly be a very serious situation of sticking steel. Now that the problem of failure has been listed, how should we prevent and solve it?

1. Strengthen the cooling of the discharging tool of the rolling mill so as to avoid sticking steel to the fastener due to high temperature.

2. Reduce the burr of the slitting box in slitting rolling and prevent the leakage of tied parts in the high-temperature area.

3. Periodically check the roll gap of the roll and the value of the roll gap of the slitting wheel, so as to effectively avoid the occurrence of sticking steel.

500,000 tons (10-39mm) Mini Rebar Mill for Sale

500,000 tons (10-39mm) Mini Rebar Mill for Sale


We have following rebar mill for sale.
Rebar rolling  mill, Walking Beam Reheating Furnace ( 95 t/ Hour )
Capacity : Rebar 10-39mm ,normally D32


Here is more detail

 Rolling Mill Maker: Hangji (H1-V18 including 3 sets of convertible (C10 &C14 &C16) and 3 sets   of  dividing shear
 Bending Machine: 2 sets
 Cooling Bed: 78m x 12m
 Production of finished products: Rebar (D10 -D39)
 Annual Capacity: 500,00 TPY

Bar and Wire Rod Rolling Mill For Sale

Bar and Wire Rod Mill Production Line

50000-300000 tons of bar and wire rod mill production line, 8-32mm of full continuous rolling production line, is common carbon steel, excellent carbon structural steel and low alloy steel; the designed annual production capacity is 50000-300000 tons, and the large line speed of finishing mill is 5-16m / s.



1. Billets: 100 × 100 -- 150 × 150 continuous casting billets with a length of 3000mm -- 6000mm are provided by the internal steel-making and continuous casting workshop of the company.


2. A new regenerative pusher reheating furnace will be built for the whole continuous rolling mill production line. The fuel is blast furnace gas and the air will be preheated by single preheating. The hourly heating capacity is 40-80t / h, end in and side out, a single row of cloth, which can meet the requirements of 50000-300000 tons of rolling material per year. The inner chamber size of the reheating furnace is 6.6x24m.

3. 16 rolling mills are adopted, which are divided into roughing mill, intermediate mill and finishing mill, forming the whole continuous rolling production line, with the layout of 6 + 6 + 4 horizontal and vertical alternation, and the main drive of rolling mill is controlled by full digital PLC. Micro tension continuous rolling is adopted for rough rolling and medium rolling. There is one side looper in the middle of medium rolling and finishing rolling, and there is a vertical looper between each rolling mill of finishing the rolling unit, forming no tension and no torsion rolling. The high speed of the rolling mill can reach 5-16m / s.


4. Three flying shears are set on the rolling line, which is located behind the three units and is respectively used for cutting head, accident breaking and finished product multiple length sections. The structure of scissors is crank type, rotary type, and crank rotary combination.


5. Rolling process: round 6.5mm, threaded steel 8-32mm. The annual output of 50000-300000 tons of material requires 330000 tons of continuous casting slab, and the comprehensive yield is 98% (negative deviation is considered).

6. Controlled rolling water piercing cooling device is set in front of the finishing mill and a controlled cooling water piercing device is set behind the finishing mill to produce high-strength steel bars (grade III steel) and improve the mechanical properties of the products.



7. Semi-automatic packing equipment and 50t cold shear are used in the finishing collection area.



8. The control system adopts computer secondary control, which is divided into four areas (heating furnace area, rolling area, controlled cooling area, and finishing area), and each control point is controlled in a decentralized and centralized way.

Production Process and Product Structure

It adopts the international advanced equipment and advanced production technology: the heating furnace is a walking beam type, adopts the double regenerative high air temperature combustion technology of energy saving and environmental protection, and uses the blast furnace gas with low calorific value as fuel, which can greatly reduce the fuel consumption, with the characteristics of fast heating speed and good heating quality.



There are 18 rolling mills in the whole line. In order to ensure the dimensional accuracy of the products, 6 loopers are set in the finishing mill room, and the water-cooling device is set after finishing rolling, which can realize the torsion-free controlled rolling of the whole line. In the production of φ 10 ~ φ 16 threaded steel, three-section rolling is used; in the production of φ 18 ~ φ 22 threaded steel, two-section rolling technology is used. Among them, φ 22 two slitting rollings is a domestic innovation, and the family has this technology, and the slitting rolling capacity is at the first level in China. The main drive of the rolling line adopts the full digital control DC motor, which can realize the automatic operation of the whole line, and the large rolling speed can reach 18 m / s. The raw materials used are continuous casting billets, all supplied by hot delivery.

The main product specifications include national standard II, national standard III, British standard, Japanese standard, plus standard Φ 10 - Φ 40 straight thread steel and round steel of various specifications.


Production steel includes ordinary carbon structural steel, excellent carbon structural steel, low alloy steel, etc. All products are delivered in straight condition.

600,000 TPY Rebar Rolling Mill | Section Mill for Sale

Mini-Metallurgical Plant and 600,000 TPY Rebar Rolling Mill | Section Mill for Sale

The Minimill plant is composed of Melting & Refining shop

FastArc TM AC 70 t tapped steel

Ladle Furnace LF 70 t

Single-tank/single-cover VD/VOD station

FTP for EAF & LF primary and secondary fumes.

Melt shop auxiliary facilities

Continuous Casting Plant: 

3-strand Danieli FastCast TM billet continuous casting machine

Rolling Mill:

80-t/h (or 100-t/h in hot charge) Bar and Light Section Mill
70-ton Ladle Furnace (12/14 MVA transformer).
70 ton VD/VOD station, single-tank, single-cover type.
Raw material handling/charging system for EAF,LF and VD
Fume Treatment Plant for primary and secondary fumes for EAF and LF E C B

The Meltshop:

  A -Arc EAF 70-ton tap weight (64/74 MVA transformer), 5.3-m shell dia, equipped with the latest generation of wall-mounted oxygen/carbon injectors. The casting of specialty and stainless steel ingots

  B -70 ton Ladle Furnace (12/14 MVA transformer).
  C -70 ton VD/VOD station, single-tank, single-cover type.
  D - Raw material handling/charging system for EAF, LF, and VD
  E - -Fume Treatment Plant for primary and secondary fumes for EAF and LF
  F - 3-strand, 9-m-radius FastCast Continuous Casting Machine, for high-speed casting of 130x130, 150x150,180x180-mm quality billets. Direct connection to the rolling mill reheating furnace, for hot-charging operation

PLANT CAPACITY: 500,000 tpy in cold-charge mode(*) Up to 600,000 tpy, in hot-charge mode

STARTING MATERIAL: Billet 150 x 150 x 12,000 mm
                                               180 x 180 x 12,000 mm Weight 2,000 kg and 3,000 kg

STEEL GRADES: Low carbon, concrete reinforcing, low/medium alloy steels

FINISHED PRODUCT:  Rounds (RB) from 16 to 50 mm dia
Deformed Bars (DB) from 10 to 40 mm dia, 4- strand slitting on DB 10, 12 mm dia 2- strand slitting on DB 14, 16 and 18 mm dia

Squares from 14 to 40mm, Flats from 30x6 to 80x25mm; Angles(equal) from 30x3 to 50x7mm; C profiles form 4 to 5

FINISHING SPEED: Up to 12 m/s

 PRODUCT TOLERANCES: According to Local and International Standards

FINISHED PRODUCT SUPPLY: Straight Bar Bundles Length 6,000 to 12,000 mm Weight 1,000 to 5,000 Kg
 (*) Yearly capacity based on a 3 daily shifts working schedule

Reheating furnace: Walking Hearth type capacity 80 t/h (or 100 tph in hot charge)

Roughing Mill: 8 AC driven ESS compact cantilever stands 820/685/585 mm dia in H and V configuration

Intermediate Mill: 6 AC driven SHS housingless stands 475 mm dia in H and V configuration.

Finishing Mill: 6 AC driven SHS housingless stands 430 mm dia in H, V and H/V convertible configuration equipped with automatic quick-changing system
In-line QTB treatment for high tensile deformed bars

Cooling Bed: Rake type Dimensions 54 x 13m equipped with a water spray system

Finishing Services: CLS on-line start&stop Straightening and Cut-to-Length system (multistrand straightener and shear), bundling service, final tying and collecting services

DANIELI AUTOMATION fully integrated system for process technology and equipment control

60,000 TPY Rolling Mill for Sale

60,000 TPY Rolling Mill for Sale

1. General specification

1-1. Production capacity:      60,000 TPY

1-2. Material:                        Billet 150sq. 160sq. 150 x 180sq. etc.

1-3. Product type & size:       Chanel 100 x50 ~ 200 x 90

                                              I-Beam 150 x 75 ~ 200 x 100

                                              Angle  90 x90 ~ 130 x130

                                              Unequal angle 100 x 75 ~ 150 x 90

2. Equipment specification

2-1. Reheating furnace       Capacity-25TPH / Type-3-zone / Skid rail

2-2. Roughing mill(R0)   2H stand / Bearing type / PCD550ø / AC motor 600kw-3.3kv

                            / 1pass

2-3. Discaller 1,2             Plunger pump type 2sets / 100~130kg/cm²

2-4. Roughing mill(R1~R4)  3H stand-1,2,3 / 2H stand-4 / Fiber metal type / PCD465ø

 / AC1500kw-3.3kv / 10pass

2-5. Discaller3,4             Ejector pump type 2 sets / 200~250kg/cm²

2-6. Inter-mill(I0)        2Hstand / Bearing type / PCD500ø / AC1500kw / 3.3kv /1pass

2-7. Finishing mill             2H stand / Bearing type / universal type / PCD800ø

/ DC1000kw / 1 pass

2-8. Cooling bed              Rack type / L32m x W11m / run in / run out / take out

2-9. Straightener              Fix H type / AC150kw / roll

2-10. Cushion bed       Rack type / L32m x W4m

2-11. Cold saw            Fix.- Moving 2 sets 

2-12. Packing conveyor        Chain move conveyor

2-13. Stand Roll & Guide

2-14. Straightener roll

2-15. Electric capacity          5,500kw / 22.9kv

2-16. Electric panel         AC mill motor operating panel / DC mill motor driver

     /Control panel / MCC panel / Local panel / Operating desk

2-17. Water treatment          Pump / Operating panel

Automatic Control Analysis of Bar Continuous Rolling Flying Shear

Flying Shear Start Control

Before rolling, the engineer's station personnel passed the screen set to transfer the cut and cut the size of the flying shear to the PLC. When the HMD detects the steelhead or steel tail signal before the shear, the detection signal is sent to the PLC that controls the scissors, and the scissors PLC then according to the line speed of the rolling piece passed by the basic PLC, the last cut of the scissors The error, and the set length of the cutting head and the tail length, calculate the flying shear start delay time. When the delay time is up, the start command of the flying shear is issued immediately, and the cutting function of the flying shear is completed. For the shredding function of the scissors, the manual start control is adopted, and the operation table manually breaks according to the accident. The shredding function of the scissors takes precedence over the function of cutting and cutting.

Rolling Steel Simulation Analysis Function

When the hot test run is not set at the production site, in order to comprehensively evaluate the linkage effect of each device, it can be completed by cold adjustment; when it is judged whether the cascade blocking function is normal, it can be analyzed by the automatic control model; When it is reasonable, it can be operated in a targeted manner, which shortens the trial hot car time to some extent. At the same time, under the action of rolling steel simulation analysis function, online simulation analysis is realized, and through the continuous improvement of offline simulation function, it provides necessary reference information for the development of transmission inverter equipment program. When the PLC is connected correctly, all module performance can be tested in real-time.

Bar Speed Correction

The rolling speed of the bar is the basis for control and the key to controlling the accuracy of the cutting, so the estimation of the speed of the rolled bar is particularly important. When the calibration function is activated, the speed of the bar is corrected. The speed of the rolled material is generally calculated by the mill control system based on the roll diameter, roll profile and motor type, due to elastic strain and rolled material at the stand roll. The actual reduction on the amount, the calculated value may not be consistent with the actual value. The actual speed is estimated by measuring the elapsed time of the end of the bar from the HMD before the flying shear to the time after the HMD. Alternatively, the flying shear performs shearing, and the measurement starts from the interlacing of the blade to the cutting. The time at which the end reaches the HMD downstream of the flying shear. The ratio of the distance between the HMDs and the measured time gives an estimate of the average speed of a bar during operation. A speed calibration factor is obtained relative to the average of the speeds calculated by the mill control system at the same interval. The speed received from the mill control system becomes a speed calibration factor, thereby obtaining the best estimate of the actual speed of the bar during shearing.

Flying shear Zero Compensation Control

After the end of a cutting process, the flying shear must be accurately parked at the zero position to prepare for the next cut. The zero detection of the flying shear is calibrated by the proximity switch. However, in practice, there is a certain error in the stop position from the original zero points. The error must be compensated to ensure that the speed of the scissors is accelerated to the set shear speed within the specified distance to meet the shear torque requirement. For this purpose, the position of the cutting edge is detected using the positioning code dial. The code wheel adopts 2048 two-phase orthogonal pulse. Each rotation of one wheel, the code wheel count is 0-8192, corresponding to the cutting edge angle of 0-360 degrees so that the angle of the scissors from the zero position can be calculated by counting the pulse of the code wheel. By this value and the angle between the zero point and the shear point, the initial angle of the flying shear can be calculated. Since the code wheel can achieve high precision and can effectively suppress the counting error caused by the vibration, the next cutting edge can be accurately compensated for the next cutting edge error.

In summary, the application of the bar shear system, the main technical performance indicators such as shear accuracy, shear section quality, shear response speed and optimized shear reliability can meet the on-site process requirements, in the rolling mill room Under the premise of normal cascading relationship, stable rolling mill speed and normal operation of all detecting components, the absolute value of the positive and negative shear length of the shearing length generally does not exceed the maximum linear velocity (m/s) of the rolling line multiplied by 5 milliseconds. The application of the automation control system has improved the production level to a certain extent, which is an inevitable trend in future development.

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Advantages of Hot Rolling Mill

Advantages of Hot Rolling Mills

According to the hot rolling mill manufacturer, the rolling mill is indispensable equipment in modern metal rolling, and we can use two different methods. For example, you can choose hot rolling or cold rolling. Obviously, the two methods are relative.

In fact, what we mean by hot rolling is mainly a process in which rolling is completed above the recrystallization temperature. Roll mill professional manufacturers believe that the use of hot rolling can enjoy some benefits, then, do you know the main advantages of which? Let's take a look at the main content of this aspect.

The mill manufacturer explained that the advantages of the hot rolling mill can be summarized into three aspects. First, the use of hot rolling can significantly reduce energy consumption and reduce costs. In addition, high-metal plasticity can be exerted during hot rolling, and the deformation resistance generated is small, and the metal can be effectively prevented from being severely deformed.

According to the rolling mill manufacturer, the second advantage of using hot rolling is that it can properly improve the processing performance of metals and alloy materials. That is to say, it can crush larger crystal grains and reduce the occurrence of cracks, which is equivalent to reducing defects in the casting process and improving the processing properties of the alloy.

The last advantage is that the hot rolling process is more conducive to continuous and automated. The rolling mill professional manufacturer explained that in this process, we generally use large ingots to reduce the amount of rolling, so it can also improve the efficiency of the work while creating favorable conditions for increasing the rolling speed.

The above is the main advantage of the use of hot rolling by the rolling mill professional manufacturers. I believe that everyone has a clear understanding of this content.

Purchasing Rolling Mill Equipment Quality Priority

Priority Should be Given to Quality When Purchasing Rolling Mill Equipment

Such important processing equipment as rolling mill must be carefully considered when purchasing. Of course, many users will pay more attention to the price first, but also need to consider the quality of the equipment as much as possible.If conditions permit, it is best to visit the rolling mill manufacturer for consideration, so as to see the manufacturing technology of the equipment manufacturer, and also to ensure that the equipment purchased can be put into use after installation.

In fact, when selecting and purchasing rolling mills, the quality and performance of the equipment should be considered first. Because of the quality is not guaranteed, there may be a lot of unnecessary troubles in the later use period, and even may lead to unusable, so we need to give priority to the quality of products, and then choose.

At the same time, the selected new mill also needs to comply with the relevant requirements when it is installed. There are many differences between different rolling mills, so it is necessary to carefully read the instructions for the use and installation of the equipment when installing.Especially when the electronic control system is installed, special attention should be paid to it. Because of the long process layout of rolling line, the requirements of the mutual elevation difference and centerline between the equipment are stricter.


In addition, in the installation operation, it is necessary to select the appropriate installation location. If equipment on rolling line is installed on soft ground, the uneven settlement and displacement of equipments need to be taken into account. This is also the reason why the equipments need to bury the settlement observation points on the basis of central benchmark, datum point, and rolling mill before installation, and make regular measurements. Only when the settlement and displacement become stable can the equipment be adjusted accurately.

In addition, in the work of rolling mill, due to the heavy load, special attention should be paid to the selection of suitable roller bearings. Usually, the mechanical properties of hot rolling mills are better than those of rolling mills, and the properties of steel products are naturally better.

Continuous Rolling Mill

Continuous Rolling Mill

The main working principle of continuous rolling mill is that when the billet is heated and discharged from the furnace, the oxidized iron sheet is removed by high-pressure water, and then the billet is processed in a four-roll reversible roughing mill. Finally, the intermediate billet which we need and suitable for continuous rolling mill is rolled. In the process of billet opening, the vertical roll can effectively ensure the precise width of the steel plate and the intermediate billet. After shearing, it will directly enter the continuous rolling mill to wait for processing and can be rolled to the specifications required by customers at one time. After rolling, the coiler will take up the coil. In the process of rolling, the roughing and finishing mill needs high-pressure water for secondary dephosphorization.

Introduction of Four-roll Continuous Rolling Mill:

Main Uses: This kind of mill is a one-way and irreversible four-high cold rolling mill. It is mainly used for rolling stainless steel, aluminum, carbon steel, copper and zinc, and other metals.

Main Features and Structures: The main components of this rolling mill are reducer, motor, universal joint shaft, human gearbox, stand, pressing part, electronic control cabinet, and roll system. The roll system uses special bearings for continuous rolling mill. The material of roll is 9Cr2Mo. If it is a large mill bearing base, it will also have a roll changing device.