Large and medium ¨Csize ladle inner lining endless gunning welding technology

 

The endless ladle gunning welding technology is a new patent technology of ladle lining infinite loop based on the original endless ladle lining welding technology, and developed by INTOCAST of German and Jinan New Emei Co., Ltd of China.  it is an application of combining old and new. By the reaction welding principle between castables and steel slag on the surface of remaining lining it will combine the new lining and old lining and and achieve the endless loop renewal lining of ladle inner lining . Using in medium and large refining ladle in place of ordinary magnesium carbon brick for lining up, it will reduce more than 30% of the same level materials cost, substantially reduce the labor intensity (due to no removal of residues lining), and bring remarkable economic and social benefits.

 

The original endless ladle gunning welding technology must handle surface galling of the residual lining during the welding process with the residual lining in order to guarantee the combining performance, meantime, because of the different sintering propensity and slag system, it is also different surface galling on the residual lining, so it need more higher request on galling equipment, but the new developed gunning welding technology can mend this problem by gunning and Lining repaired directly without do anything on the surface of residual lining. In use process it achieve the welding with residual lining and gunning refractory, reduce the cost of endless ladle inner lining, improve its life, decrease the labor intensity. Comapring with the ladle inner lining welding technology, it has the characteristics of a high degree of automatic,low cost, longer life, no environment pollution, cleansing the steel and so on.

 

In Laiwu Steel plant, it has achieved the LF+HR refining process. After implement the endless ladle gunning welding technology, the life time increased from 78 heats to present 190 heats and decrease the unit steel cost greatly, improve the ladle utilization, substantially reduce the labor intensity and so on. The below mentioned are the equipment pictures during the the process of implementing

 

l  Comparisons between the endless ladle gunning welding technology and the traditional ladle lining:

 

In China, MgO-C refractories are widely applied to ladle working lining. A large quantity of bricks are to be stored along with the increasing production. Due to the large amount, package charge (including cost and labor) is a heavy burden.

 In addition, smoke gases and exhaust fumes produced when heating the MgO-C ladle lining in the refractory plant do a great harm to the environment and the staff as well. Not only the disposal of the large nuber of waste after use, but also the process of turning into by product may add a considerable additional cost.

 

Meanwhile, the increasing output calls for continuous decrease of rebuilding lining frequency. Although the MgO-C brick has been applied for a long time and adapted to the requirements in steel plant. However, as to brick lining, neither cutting down on workforce nor partial automation is possible.

Due to serious energy and environmental issues, both refractory enterprise and steel enterprise encounter great cost pressure. Thus, developing the endless ladle gunning welding technology is essential to saving workforce, achiving partial automation, and environment friendly ladle lining.

 

From this perspective, the endless ladle gunning welding technology has the following advantages compared to brick lining:

 

1 To keep warehouse space to a minimum (the material consumption is the original 1/4).

2 Without packing the material (all material is placed in sock bin).

3 Heated gases are pollution-free.

4 To improve the utilization of ladle. E.g., life expectancy increased by 200%.

5 To reduce the demoliton, and lower to 10% of the original workload (Including environment pollution, and waste disposal costs, etc.).

 

l  Economic benefit and society benefit of Endless gunning welding technology

 

First, high-purity endless gunning technology has the lowest refractory consumption of unit steel in all ladle inner material at present(the unit steel refractory consumption of ordinary ladle castable is 3.4kg, the unit steel refractory consumption of magnesia-carbon brick and alumina-magnesite carbon brick is 2.9kg, the