LMM TOTAI offer a complete product and service portfolio for all steelmaking processes.
From basic and non-basic bricks and mixes, slide gate plates, isostatic products and prefab components to special machinery, mechanisms and repair systems.
Magnesia dolomite For eaf
Magnesia-dolomite materials for EAF hearth
| Use | Bland | |||
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Sleeve of electrode： | precast block | LY-CFC-18RX |
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Work bricks： | MgO-C bricks | LY-S-NSA-110XMA | |
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Permanent bricks： | magnesia bricks | LY-HPT-B | |
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Stamping materials（dry setting）: | magnesia-dolomite | LY-S-MD-DV | |
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Eccentric bottom tap hole： | Terminal block：Al2O3-SiC-C bricks | LY-ASG-X | |
| Tapping tube： MgO-C bricks | LY-MG-15SX | |||
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Electrode of furnace bottom： | MgO-C bricks | LY-MG-16BSX | |
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Gunning repairing material: | magnesia-dolomite materials | LY-G-HD100 |
Wet type of stamping material, which magnesia is mixed with bittern solution and molded by rammer, is generally used for lining material for hearth of electric arc furnace. However, in case of severe operation conditions on hearth of DC furnace or any, dry type of magnesia-dolomite stamping material which emphasizes sinterability is mainly chosen. YOTAI supplies kinds of materials introduced below.
Wet Type Stamping Material
- Superior in slag corrosion resistance.
- Grades are divided by magnesia raw material.
- Mix after adding bittern solution or Magnesium Chloride powder with water
- Constructed by rammer or vibrating stamping machine.
| LY-S-MT –DV | LY-S-MT-DV2 | LY-S-MT-DV3 | LY-S-MT -DP | ||
| Chemical Composition (%) | MgO | 93 | 95 | 94 | 93 |
| SiO² | 3 | 2 | 2 | 4 | |
| Grain composition (%) | Maximum grain | 5mm | 5mm | 5mm | 5mm |
| 1.2mm< | 47 | 47 | 47 | 47 | |
| 0.09mm> | 23 | 24 | 23 | 21 | |
| balanced with both sinterability and corrosion resistance by using seawater magnesia clinker. | corrosion resistant type by using fused magnesia clinker. | sinterable type by using natural magnesia clinker. | adjusted grain sizes for rammer by using seawater magnesia clinker. |
Dry Type Stamping Material
- Superior to sinterability. Dense and high intensity construction can be offered.
- Grades are divided by amount of dolomite material.
- Constructed by vibration fabrication in dry condition.
| Brand | LY-S-MD-DV56 | LY-S-MD-DV65 | LY-S-MD-DV30B | LY-S-MD -DV | |
| Chemical Composition (%) | MgO | 80 | 73 | 84 | 85 |
| CaO | 13 | 17 | 12 | 10 | |
| Fe₂O₃ | 1 | 3 | |||
| Grain composition (%) | Maximum grain | 10mm | 10mm | 10mm | 10mm |
| 1.2mm< | 48 | 48 | 51 | 49 | |
| 0.09mm> | 17 | 17 | 21 | 22 | |
| CCS (MPa) 1500℃x3h | 65 | 78 | 80 | 90 | |
| Added materials | Magnesia | □ | □ | ○ | ○ |
| Dolomite | ○ | □ | ○ | □ | |
| Iron bonded Magnesia | × | × | ○ | □ | |
| basic type. | improved sinterability by increasing amount of dolomite. | improved sinterability by adding iron bonded magnesia clinker. | improved sinterability the most. Suitable in front of work door of DC furnace and around electrode circumference of DC furnace bottom. | ||
Magnesia-dolomite materials for EAF repairing
| Use | Bland | |||
 |
|
Sleeve of electrode： | precast block | LY-CFC-18RX |
|
|
Work bricks： | MgO-C bricks | LY-S-NSA-110XMA | |
|
|
Permanent bricks： | magnesia bricks | LY-HPT-B | |
|
|
Stamping materials（dry setting）: | magnesia-dolomite | LY-S-MD-DV | |
|
|
Eccentric bottom tap hole: | Terminal block：Al2O3-SiC-C bricks | LY-ASG-X | |
| Tapping tube： MgO-C bricks | LY-MG-15SX | |||
|
|
Electrode of furnace bottom: | MgO-C bricks | LY-MG-16BSX | |
|
|
Gunning repairing material: | magnesia-dolomite materials | LY-G-HD100 |
These materials are applied for hot gunning for electronic furnace repair, and used of basic gunning material in general. Yotai consider for various kind of materials and develop the materials to get the satisfaction by user, and the introduction is mentioned as below.
- We have general type using virgin materials, and cost cut type using recycled materials.
- Our general type has Magnesia G-E series for corrosion resistance, Magnesia dolomite G-MD/HD series for Sinterability to wall of furnace and Magnesia spinel type of G-E1SP/BSP8 for suitable to operation in low C/S slag line.
- Our cost down type has Magnesia Chrome G-R2Y, that is made by recycled material. The recycled material after using at the furnace is provided by steel manufacturer, and is done for sizing and grading.
Chemical composition, grain composition and features
Table 1 Magnesia type
| LY-G-E1 | LY-G-E3T | LY-G-E7S | LY-G-E8S | |
| MgO | 88 | 89 | 91 | 91 |
| SiO2 | 3 | 3 | 3 | 3 |
| CaO | 2 | 2 | 2 | 2 |
| Maximum grain | 5mm | 5mm | 5mm | 3mm |
| 1.2mm< | 40 | 40 | 45 | 35 |
| 0.09mm> | 29 | 29 | 28 | 33 |
| General type by natural magnesia | Fine part of material of sea water magnesia, and improved for corrosion resistance | Material of sea water magnesia, further improvement for corrosion resistance | Main material of sea water magnesia, and grain composition for good adhesion |
Table 2 Magnesia dolomite type
| LY-G-MD-EN | LY-G-HD50 | LY-G-HD100 | ||
| Chemical composition(％) | MgO | 83 | 68 | 70 |
| SiO2 | 4 | 4 | 3.5 | |
| CaO | 7 | 22 | 23 | |
| Fe2O3 | 1 | 2.5 | 2.5 | |
| Grain composition（％） | Maximum grain | 5mm | 5mm | 5mm |
| 1.2mm< | 40 | 45 | 45 | |
| 0.09mm> | 27 | 28 | 28 | |
| Feature | Based material of G-E1, additional of dolomite to get sinterability | Use of high calcium dolomite for improvement of sinterability, and material of natural magnesia | Base material of G-HD50, and use of sea water magnesia |
Table 3 Magnesia spinel、Magnesia chrome
| LY-G-E1SP | LY-G-BSP8 | LY-G-R2Y | ||
| Chemical composition(％) | MgO | 85 | 78 | 81 |
| SiO2 | 3 | 3 | 5 | |
| CaO | 2 | 2 | 2 | |
| Al2O3 | 6 | 15 | - | |
| Cr2O3 | - | - | 5 | |
| Grain composition（％） | Maximum grain | 5mm | 5mm | 5mm |
| 1.2mm< | 40 | 43 | 40 | |
| 0.09mm> | 29 | 29 | 29 | |
| Feature | Base material of G-E1, additional of spinel | Main material of spinel | Base material of G-E1, and additional of recycled magnesia chrome | |