Carbon-free refractories for ladle working lining

Carbon-free refractories are high quality, environmental friendly and energy-saving materials developed as ladle working lining for low-carbon and ultra-low carbon steel production. Those refractories are characterized with high strength, high erosion resistance, high corrosion and penetration resistance and long service life. As the matrix is composed of calcium aluminate cement, superfine powder and in-organic additive, there is no generation of toxic gaese in pre-firing and in service, which is environmentally friendly and at same time free of H pick up in molten steel. As there is no carbon materials in the product, C pick up by molten steel is eliminaten and the the decrease of molten steel temperature is less due to better thermal insulation given by low thermal conductivity, which is help for energy saving.

There are three types of carbon-free refractory products for ladle working lining from LMM GROUP

1. Castable: Casting, curing, drying and pre-firing are done on the site of steel mill. The lining is joint-free with longer service life
2. Pre-cast shape: Casting, curing, drying and pre-firing are done on the site of LMM GROUP In comparison with castable, it does not require infrastructure for on-site casting and can shorten installation process for high ladle utilization.
3. Carbon-free brick: The bricks are pressed, cured and pre-fired before delivered to steel mill for on-site brick installation
4. Spraying Mix: carbon-free and environment-protected wet spraying technique is adopted to realize the cycle use of ladle lining materials, with characteristic that long life time, low cost, safe use, and environment protection.

Castables for working lining

This series of products is made from high purity corundum, magnesium aluminate spinel and fused MgO as main aggregates, superfine powder bonding technology and appropriate additives. Products are featured with good placement properties, high strength, better volume stability, better corrosion and abrasion resistance and thermal shock resistance and designed for bottom and sidewall lining of large- and medium-size ladles together with MgO-C brick for slag zone. It can also be used in slag zone of small-size ladle. In case of re-lining technique is applied, the life of ladle lining can be further prolonged and refractory consumption per ton steel produced can be further reduced, which is proven to be an effective way for low specific refractory consumption and resource saving.

Castables for working lining

This series of products is made from high purity corundum, magnesium aluminate spinel and fused MgO as main aggregates, superfine powder bonding technology and appropriate additives. Products are featured with good placement properties, high strength, better volume stability, better corrosion and abrasion resistance and thermal shock resistance and designed for bottom and sidewall lining of large- and medium-size ladles together with MgO-C brick for slag zone. It can also be used in slag zone of small-size ladle. In case of re-lining technique is applied, the life of ladle lining can be further prolonged and refractory consumption per ton steel produced can be further reduced, which is proven to be an effective way for low specific refractory consumption and resource saving.

Carbon-free brick for working lining

High purity corundum, magnesium spinel and fused MgO are selected as main aggregates for this series of bricks. Those products are used for the bottom and sidewall of ladle and featured with high corrosion resistance, better penetration resistance, good anti-spalling and abrasion resistance. The quality and performance of those products are the benchmark in china.

Working layer spraying mix

Main raw materials of this kind of product are corundum and magnesium aluminate spinel, after spraying use on the working layer surface in carbon-free ladle, characteristic appear as follow:

1. Wet spraying technique has no pollute to environment and no CO2, CO when using in carbon-free ladle, and its geared to the carbon-free and environment- protected and environment-friendly technique.
2. This spraying mix could be endlessly cycle used to lower the refractory material consumption and waste appearance and work with key role on the ladle continue and safety use.
3. This spraying mix has no pollute to the molten steel, and, compared with the current lining materials, it has the characteristic that long lifetime, low cost, high construction automaticity, and energy conservation and environment protection. High potential value among the inland steel enterprise.

Carbon containing refractories for ladle working lining

Three types of carbon containing refractories are developed and produced by LMM GROUP to be used for ladle lining, which can be summarized as follows.

1. The series of carbon bricks: Low carbon MgO-C and Al2O3-spinel bricks with carbon content below 5%, used for low carbon steel production
2. The series of Al2O3-MgO-C bricks: Al2O3-MgO-C and MgO-Al2O3-C bricks with carbon content above 8% .Those products are featured with high corrosion and erosion and erosion resistance and good thermal shock resistance and used for normal carbon and high carbon steel production
3. The series of MgO-C bricks: High quality magnesite and graphite are used as main materials for the bricks. Those products are featured with high corrosion and erosion resistance. Good thermal shock resistance and high volume stability and used for normal carbon and high carbon steel production

Low carbon MgO-C bricks

Base on high quality magnesite and graphite as main raw materials, a series of products are produced via pressing and low temperature pre-baking and mainly used in slag zone of ladle lined with low carbon or carbon-free refractories for low and ultra-low steel production. The products have high strength, good corrosion resistance and excellent thermal shock resistance.

Low carbon Al2O3-spinel bricks

Fused alumina, magnesium aluminate spinel, fused MgO and graphite are the main raw materials in use for those bricks. This series of products, featured with high strength, better corrosion resistance and thermal shock resistance, are mainly used in the bottom and sidewall for low and ultra-low carbon steel production.

Al2O3-MgO-C bricks

This series of products are made from corundum, magnesium aluminate spinel, super-grade bauxite, high quality MgO and graphite as main raw material and phenolic resin as binder. The products are mainly used in the bottom and sidewall of ladle with better corrosion and erosion resistance as well as good anti spalling performance.

MgO-bricks

This serice of MgO-C bricks are made from fused and large crystallized MgO and graphite as main raw material and phenolic resin as binder. The bricks are pressed under high pressure and thermal treated at low temperature. The products are mainly used in slag zone of ladle with better corrosion resistance and anti-spalling performance.

MgO-Al2O3-C bricks

This series of bricks are made from high quality fused MgO, fused corundum and graphite as main raw materials and phenolic resin as binder. The products are mainly used in the bottom and sidewall of ladle with better corrosion and erosion resistance.

Monolithic castables for safety lining

This series of castables are composed of corundum, high quality bauxite, superfine powder and other ingredient and featured with good workability on site casting, high strength, high volume stability and long life span. Those products can be used for the permanent lining of ladle of all sizes and proven to be better on service life and safe steelmaking operation

Porous plug

Porous Plug developed by LMM GROUP for ladle bottom gas purging takes the lead in the products of the kind not only in China but also in the world. Based on customers needs, various types of porous plug can be designed and produced including directional channel, slit type, multipath

Unburnt slide gate plates

Unburnt slide gate plates are composed of corundum, mullite, super-grade bauxite, graphite SiC and Si as main materials and produced via high speed mixing, high pressure pressing, thermal treatment under low temperature and surface grinding and stainless steel looping. The series of products are characterized with high strength under high temperature, better anti-oxidation and excellent thermal stability, which has been used various steel mills including rongcheng steel(ladle of 110mt) and Tangshan kaiheng steel (ladle of 120mt) with good performance on less erosion on slide surface, small bore enlargement and longer life in casting operation.

Fired slide gate plates

High temperature fired slide gate plates developed by LMM GROUP are produced via high speed mixing, high pressure pressing, high temperature firing, vacuum and pressurized pitch impregnation, precise surface grinding and hot stainless steel looping processes. The products have low impurity and stable on quality. Good performance on strength, erosion resistance and thermal shock resistance enables the slide gate to cast multiple ladles of molten steel.

LMM GROUP can produce and provide Al2O3-C or Al2O3-ZrO2-C based slide gate plates to meet various ladle working condition and special customers needs.

Nozzle and well block

Upper and collect nozzles are resin bonded products based on corundum, magnesium aluminate spinel and graphite as main raw materials. The products have excellent thermal shock resistance, high temperature strength and good corrosion and erosion resistance.

Well blocks of corundum based , corundum-spinel based and corundum-chrome based have excellent high temperature properties, which can ensure longer service life in use together with nozzles as part of slide gate system.

Fillers for ladle tapping hole

LMM GROUP can supply Silica-based and Chrome-based filler according to customer’s requirement. Silica based filler use quartz sand as raw materials, mixed with lubricant and sintering aid.

Chrome-based filler use South-Africa Chrome ore as Raw materials, mixed with lubricant, sintering aid, deoxidizer and etc. features good self-flow rate, normally above 95%:

LMM GROUP Series of fillers for ladle tapping hole can be used for kinds of ladle, LF ladle, Show the features of non-floating , high self-open rate, easy installation and safety.

Refractory mortar

Various kinds of refractory mortars are available at LMM GROUP, which include corundum based, corundum Cr2O3 based, high alumina based and Al2O3-MgO based. The mortars perform well in use with excellent workability, desirable hardening time, high adhesive strength, high strength and corrosion resistance under high temperature.

Fluid field simulation

Equipped with state-of-art water simulation and digital modeling lab for thermal devices used for steelmaking, LMM GROUP can provide steel mills with lab simulation on fluid, thermal filed and particle movement track, etc. of high temperature devices such as ladle, tundish and re-heating furnaces. Those simulation can provide scientific evidences to design better and long lasting refractory lining for ladle and tundish

Comprehensive refractory design

The selection of refractories and zone lining concept are the important parts in comprehensive refractory management for high temperature devices.

Based on water simulation and modeling tests and enriched experience of our technical staff, LMM GROUP can design and provide the mostly appropriate refractories and zone lining as per customers needs and working conditions of different zones in ladle lining so as to increase the service life of refractories .

Design and production of mould and installation tool

The design of moulds and necessary tools for refractory installation is also the important part for comprehensive refractory management

The project and design team at LMM GROUP is composed of talent professionals from mould design , mechanical processing and thermal engineering. Together with refractory engineers, they can develop unique equipment and tools for refractory installation and maintenance according to the needs on site. Those equipment and tools can ensure fluent and effective installation and also refractories, provided by LMM GROUP, to reach the maximum performance. The mould, designed especially for the installation of monolithic working lining and safety lining, is patented by LMM GROUP.