The world No. 1 in crude steel production steel plant, over 70% of the HSS for bar and wire are from us.

Cemente carbide composite roll

Brand name: LMM GROUP
Packing Details : Wooden box with fumigation or Wooden Fram
Delivery Details: 30~60days or Based on the quantity
Shipping: Sea freight、Land freight、Air freight

LMM have been supplied to world’s top steel manufacturer Arcelormittal, TATA Steel, EZZ steel etc. We do OEM for Concast and Danieli for a long time

Manufacture drawing

Process schedule with ETD date

QC checking of each process

Checking report

Photos &videos of each process

ISO 9001 certificate

Warranty Time

The third party Checking

Cemented carbide roll rings (also known as tungsten carbide roll ring) possesses good thermal conduction property. Compared with pther materials, it is much better in terms of heat-resistance, wear-resistance and strength. What’s more, it shardness reduces a little under the condtion of high temperature. So, the cemented carbide roll rings is invented with the ap-pearance of high speed wire rod mill. With the development and improvement

Application: it is widely applied in the production of high speed wire, bar and deformed steel bar.

tc-ring

Cemente carbide composite roll

The cemerted carbtide composite roll i mainly used on the finishing rnill for bar, deformed steel bar and common wire. In this way, wecan greatly reduce the frequency of changing grove and rol, thus to reduce the labor intensity and improve the woik efficiency. Thesurface quality and yield shall be improved to a maximum degree, which leads to a remarkable economic benefit.
Our cemerted carbide compcsite roll adopts a special grade of cemented carbide.By means of hydraulic lock nut,the cementedcarbide rollrings is fastened to the axle with the axial pressure of 2OOMpa from hydraulic oil. Under the protection of prestress, thecemented carbide composite roll shall work more effectively.

Extemal diameter(mm)Width(mm)Rolling size(mm)
285-48050-1405-28

Grade

Chemical composition

Physical mechanical properties

Wc

Co/Ni/Cr

Density g/cm3

Hardess

HRA

Bending strength

≥N/mm2

LMM-PL20F

80

20

13.5

82.5

2650

LMM-PL22F

78

22

13.3

82.0

2600

LMM-PL25F

75

25

13.1

80.5

2550

LMM-PL30F

70

30

12.6

79.5

2450

LMM-PL32F

68

32

12.5

79.0

2400

Production Process & Equipment

Product design→ Roll blank design→ Roll blank manufacturing→ Roll blank acceptance→ Annealing→ Rough turning→ Ultrasonic flaw detection→ High temperature quenching→ Low temperature tempering→ Ultrasonic flaw detection→ Finishing→ Ultrasonic flaw detection→ Roll body grinding→ Roll numbering→ Inspection→ Cleaning → Packing → Shipping → Warehousing → Inspection → Use and Maintenance → On-site Communication → Design Improvement.

As can be seen from the flow chart, roll manufacturing forms a closed-loop system from product design, production and manufacturing, use and maintenance, and improved design, and the quality of rolls is constantly improving.

Whole process supervision of the quality of raw material

LMM tries its utmost to meet the demand of customers. Our professional R&D department and production line will provide the direct and effective quality and service for you.

With over twenty years’ experience on the production of cemented carbide roll rings, LMM has established an inte-grated system including R&D and extraction of powder and production and marketing of alloy . Through our professional service, you can make the correct choice for the material to match your product.

Production Process and Production Facilities

composite rolls

Raw material:

The main raw material is tungsten carbide powder. LMM funded 20,000,000.00 USD, and imported the carbide powder manufacture equipment in 2010.
Tungsten carbide powder is produced by APT, and burning in electric heating rotary calcination furnace, and then come into being blue tungsten oxide, then through burning and producing the tungsten powder.

Screened & Classified:

The tungsten powder is screened by a vibrating screen. And then through the air classification equipment, it is classified into different granularity.

Ball Milling & Mixxing:

Tungsten powder in a certain proportion, adding carbon black and other additives after ball milling and mixing.

High Quality TC Powder:

The tungsten powder with good carbon black is added to the intermediate frequency carbonization furnace. In the end, the WC the powder was milled by the ball milling machine, and the high quality tungsten carbide powder was produced.

Forming Powder:

The WC powder, cobalt powder, and other rare elements are formulated in good proportion. Join the ball mill through the 24 hours of wet grinding, and mixed into the forming powder, then put them into the spray drying tower.

Press & Burning:

Compression molding will be prepared and put the powder into the mold, press molding with a hydraulic press; Put the roughcast into the furnace and burn it into the roll roughcast.

Finish Machine:

Through flat grinding, internal hole grinding, and cylindrical grinding comes into being the product of the ring. Also according to different rolling, different rolling mills, processed into wire grooved roll rings, wire thread roll rings, bar combination rolls, and roll steel.

Data table of grades and properties of tungsten carbide roller

GradeWc(%)Co(%)Ni(%)Cr(%)Density g/cm³ ±0.15Hardness≥HRA ±0. 5Bending strength≥N/mm²
LMM08R92814.788.02800
LMM10R901014.587.52750
LMM12R881214.286.02700
LMM15R851514.185.02650
LMM18R821813.783.52650
LMM20R802013.583.02600
LMM25R752513.182.02500
LMM30R703012.780.02400
LMM32R683212.579.02400
LMM06H9460014.889.02580
LMM08H9280014.788.52600
LMM10H90100014.588.02700
LMM15H85150014.185.02700
LMM20H80200013.583.02700
LMM25H75250013.181.52550
LMM30H70300012.780.02500
LMM32H68320012.578.52400
YGR20901014.487.52650
YGR25881214.386.52600
YGR30851514.285.02550
YGR40821813.783.52500
YGR45802013.582.52400
YGR55752513.180.52450
YGR60703012.879.02250
YGH40T851514.184.52700
YGH45T802013.583.02600

Tungsten Carbide Rolls Application

The cemented carbide composite roll is mainly used on the finishing mill for bar, deformed steel bar and common wire. In this way, we can greatly reduce the frequency of changing groove and roll, thus to reduce the labor intensity and improve the work efficiency. The surface quality and yield shall be improved to a maximrurn degree, which leads to a rernarkable ecornmoic benlefit.

ln accordance with the production line and rolling technology of customers, our products are designed to match one-strand rolling, two-slitting rolling and three-slitting rolling. three-slitting rolling, and four slitting rolling, The cemented carbide composite roll includes K1 finished roller, K2 leder roller,K4 pre-slitting roller.K3 slitting roller with high-speed steel as material. The rolling varieties include wire, bar and deformed steel bar.

Recommended applications of grades for carbide roll rings

GradeRecommended applications
LMM08RMaximum hardness, excellent wear resistance in the series. Used in the last 1~2 stands of good high-speed rolling mills for rolling common and hard steel bars.
LMM10RHigher wear resistance. Mode rate impact resistance in the series. Used in the last 1~2 stands of good high-speed finishing rolling mills for rolling common and hard steel bars.
LMM12RHigh wear resistance and corrosion resistance. Used in the last 1~4 stands of finishing mills.
LMM15RModerate wear resistance and impact resistance, good for general purpose. Used in the last 1~4 stands or all stands of finishing mills.
LMM18RGood toughness and thermal crack resistance, good for general purpose. Used in most stands of the finishing mills and the rear stands of common mills.
LMM20RBest for general purposes. Used in the front stands of good rolling mills and in the rear stands of common rolling mills.
LMM25RUsed in the first and second stands of finishing rolling mills and in the stands of pre-finishing rolling mills. For every stand of rolling lines for tow speed rolling low precision and unstable operations.
LMM30RMaximum binder content in LMMR series, good toughness and thermal crack resistance. Used in the stands of pre-finishing rolling mills and for rolling rings for hot rolling of ribbed steel.
LMM32RWith good toughness and impact resistance, used for bar, deformed bar finish stand rolling.
GradeRecommended applications
LMM06HIt possesses the highest hardness and the best wear-resistance among all the varieties of cemented carbide roll rings, thus used for the rolling of common wire and hard wire on the last 1~2 stands of high- speed wire rod finishing mill.
LMM08HIt possesses better wear-resistance and moderate impact-resistance with the hardness second to LMM06H among all the varieties, thus used at the last two stands of high-speed wire rod finishing mill.
LMM10HIt possesses the moderate wear-resistance and impact resistance, thus used at the last 3~4 stands of high-speed wire rod finishing mills.
LMM15HModerate wear resistance and impact resistance, good for general purpose. Used in the last 1~4 stands or all stands of finishing mills
LMM20HBest for general purpose. Used in the front stands of good rolling mills and in the rear stands of common rolling mills.
LMM25HMaximum binder content in LMMH series, good toughness and thermal crack resistance. Used in the stands of pre-finishing rolling mills and for roll rings for hot rolling of ribbed steel.
LMM30HMaximum binder content in LMMH series, good toughness and thermal crack resistance. Used for roll rings for hot rolling of ribbed steel and in the stands of pre-finishing rolling mills.
LMM32HWith good toughness and impact resistance, used for bar, deformed bar finish standing rolling.
GradeRecommended applications
YGR20High wear resistance and corrosion resistance. Used in the last 1~2 stands of finishing mills.
YGR25High wear resistance and corrosion resistance. Used in the last 1~3 stands of finishing mills.
YGR30Good toughness, wear resistance, corrosion resistance and thermal crack resistance. Used in the middle and rear stands of finishing mills.
YGR40Good roughness and thermal crack resistance, good for general purpose. Used in the most stands of the finishing mills and in the rear stands of common mills.
YGR45Good toughness and thermal crack resistance. Used in the front stands of finishing mills.
YGR55Good impact resistance. Used in the stands of pre-finishing rolling mills for hot rolling ribbed steel bars and they can be machined with turning and milling.
YGR60Good impact resistance. Used for hot rolling ribbed steel bars and in the first and second stands of pre-finishing rolling mills.
YGH40TWith good toughness and shock resistance, used for preferably high speed wire rolling machine, rolling small size deformed bar finish stand.
YGH45TWith good toughness and shock resistance, used for general high speed wire or common rolling machine, rolling small size deformed bar finish stand

Advantages of Tungsten Carbide Rolls

HBW05 is a new type of material specially developed by our company for KOCKS rolling mill bar production line. The hardness of the roll surface is HSD84-89, the uniformity of the roll surface hardness: ≤3HSD, the hardness drop/mm: ≤2HSD. The hardness difference of 3 roller rings of the same hole type is less than or equal to 3HSD. Single grinding amount (reduction): ≤1 mm. The material has high wear resistance and impact toughness under thermal load, so the product has high wear resistance and impact toughness, no ring burst phenomenon, and low processing difficulty. Its steel passing capacity can reach 60-80% of the cemented carbide roller ring, the price is less than 50% of the alloy roller ring, and the frequency of slot changing can reach 2 shifts.

It can be seen from the metallographic photos that the metallographic structure of the Cementer carbide roll is much better than other materials in terms of the shape, quantity, size and distribution of carbides, as well as the matrix structure and grain size.

During the use of Cementer carbide roll , under good cooling conditions, a thin and dense oxide film is formed on the surface of the roll body. This uniform, thin and dense oxide film can exist for a long time without falling off, so that the wear resistance of the Cementer carbide roll is significantly improved.

  • Cementer carbide roll have good thermal stability, and the roll surface has high hardness and good wear resistance at rolling temperature.
  • Cementer carbide roll has good hardenability, and the hardness from the surface of the roll body to the inside of the working layer hardly decreases, thus ensuring that the roll has the same good wear resistance from the outside to the inside.

Main chemical composition of the material

composition

C

Si

Mn

P

S

Cr

Proportion(%)

1.3-1.6

0.3-1.0

0.4-1.2

≤0.03

≤0.03

3.75-4.4

composition

Ni

Mo

V

W

Nb

Co

Proportion(%)

0.5-1.5

3.0-6.0

3.0-6.0

4.0-6.5

0.5-1.5

≤1.0

Testing standards

Design specifications and standards for manufacturing, quality control and inspection

The relevant standards of the roller ring are as follows:

  • Anti-rust packaging implements GB/T1504 and GB/T1503-2008 standards.
  • Sampling method of samples for chemical analysis of GB222 steel and allowable deviation of chemical composition of finished products
  • GB223 Chemical Analysis Methods of Steel and Alloy
  • GB/T13313 Roller Shore Hardness Test Method
  • GB/T1804 General Tolerances Tolerances of linear and angular dimensions without tolerances
  • GB/T1503-2008 National Standard for Cast Steel Rolls

    Testing regulations:

  1. Check the size and surface quality of each part one by one;
  2. Carry out ultrasonic flaw detection three times one by one;
  3. Carry out hardness test piece by piece;
  4. The depth of the hardened layer of the roll body is affected by the manufacturing process.
Precautions for use

Before determining the grade of cemented carbide for every stand, we shall have a thorough understand about theirproperties so as to make the correct choice (Please refer to the Product manual).

The sleeve insertion and assmbly of cemented carbide roll rings shall be carried out in accordance with the requirementsof precision. There shall be appropriate space between the roll rings and axle or between the roll rings and sleeve. The fit is neither tight nor loose. You should check whether the roll rings contorms to the technological requirement and cleanthe mounting surface of roll rings, sleeve and axle before the installation. it is prohibited to beat the roll rings with hammeror other hard things while assemblying.

For YGH series medium or weak alkali water of PH>7.2
YGRFor YGR series or PH<7.2 weak acid water of PH>7.2
The content of solid particles in the water<15 milligram/L

lt is inevitable to find the microcrack on the rolling groove. The microcrack will gradually extend, stretch and deepen. The groove shall be repaired immediately while the depth of crack reaching 0.2-0.4mm. Otherwise, the crack will deepen quickly, which leads to a risk of broken roller. The range of normal yield is reguated as follows:

Stands of pre-finishing rolling mill: (3500-4000)tons

1-2 Stands of finishing rolling mill: (1800-2500)tons

3-4 Stands of finishing rolling mith(1800-2500)tons

5-6 Stands of finishing rolling mill: (1500-2000)tons

7-8 Stands of finishing rolling mill: (1500-2000)tons

9-10Stands of finishing rolling mill: (1200-1500)tons减

Stands for reducing diameters: (800-1200)tons

lt is normal to find the microcrack on the rolling groove. The groove shall be repaired immediately while the depth of crack reaching 0.2 mm. lt is necessary to prevent the roller from being broken. While repairing, we must ensure to remove the crack thoroughly. Otherwise, it will bring a potential risk to next rolling.It is difficult and inconvenient to check if the surface is polishing. To ensure the complete remove of microcrack, we can increase the grinding quantity. Under thenormal condition, the repair is controlled in the range of:

Roll rings for stands 9-10 of finishing rolling mill(0.4-0.6)mm
Roll rings for stands 1-8 of finishing roiling mill(0.7-1.2)mm
Roll rings for s~nds of pre-finishing rolling mill(1.2——2.0)mm

FAQs about tungsten carbide rolls

Carbide rolls can be used in the intermediate finishing section of the rolling mill.

LMM produces carbide rolls with outer diameters up to 550 mm.

To convert from cast iron or steel rolls to carbide rolls, LMM carbide roll product experts will work with the rolling mill to improve roll cooling, machining and handling capabilities. Most rolling mills can be easily changed from cast iron to tungsten carbide.

Due to their higher wear resistance, LMM tungsten carbide rolls last up to 20 times longer than cast iron rolls. This reduces mill downtime while increasing productivity and lowering operating costs

The minimum rolling speed that can be used with tungsten carbide rolls is one meter per second (1 m/s).

Proper cooling is essential to ensure optimal performance of carbide rolls. The recommended minimum pressure is 4 to 6 bar and 250 to 300 liters per minute per molding.

CERTIFICATION

The company strictly according to modern enterprise management requirements set up a perfectquality assurance system, and passed the ISO9001:2008 quality management system certification,ISO14001:2004 environmental management system certification, OHSAS18001:1999 occupationalhealth and safety management system certification.

Service Display

Pre-sales:
Recommend suitable products according to the actual working conditions and needs of customers.It can also bedeveloped and designed according to needs, and customized services can be provided. During the epidemic, provide remote detection technical support.

Strict quality control:
From raw materials, to the production process and befor eleaving the factory, all performance indicators arestrictly tested, and the professional QC team controls according to the process.

After-sales service:
Quality assurance and Resolution of any issues that arise 

 

What do I need for offering a quote ?

Please offer us 2D or 3D drawings (with material, dimension, tolerance, surface treatment and other technical requirement etc.) ,quantity, application or samples. Then we will quote the best price within 24h.

About Company

LMM GROUP is equipped with advanced equipment and enjoys excellent technology for mechanical and electro-plating processing. It has complete testing devices, perfect production management and strict environmental protection measures. LMM has become a major supplier of cemented carbide roll rings in the world’s steel industry with the efforts of the company’s team.

If you need to purchase, please contact our sales staff

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