Taphole Mrx is a functional refractory material that used for the blast furnace. It is just like a valve in the blast furnace. Taphole was opened when molten iron poured, and block up after it. At the same time, must insure its sufficient time.

So it decide Taphole Mrx must possess good function：

1. Easily open. When need to pour molten iron, Taphole Mrx should be easy to drill through, reduce the labor intensity；
   
2. Easily block up. It could block up the taphole after molten iron poured and insure the stablely depth of the taphole；
3. Good conglutination. Taphole Mrx that throw into the taphole must conglutinate the former Taphole Mrx well and form a complete unit to prevent the aperture；
4. Good sinter. Taphole Mrx could sinter in the low、middle and high temperature and block up the taphole in time to protect the lining bricks of furnace.
5. High abrasion and corrade. Not enlarge the aperture of taphole. Ensure 150~180 minute/time, reasonable times should be 8~10 time/day. Lighten labour intensity, decrease the consumption of raw material and at the end reduce the cost.

According to the experience of application of Taphole Mrx in the several large blast furnace, and on the basis of technique communion with Russian、Japan steel mill. Kaifeng GaoDa Charging Co.,Ltd develop and manufacture GDT-8、GDT-11 Taphole Mrx (without water).

Characteristic of GDT- 8、GDT-11:

1. Good conglutination. Taphole Mrx that throw into the taphole must conglutinate the former Taphole Mrx well and form a complete unit to prevent the aperture；
2. Good sinter. Taphole Mrx could sinter in the low、middle and high temperature and block up the taphole in time to protect the lining bricks of furnace；
3. High abrasion and corrade. Not enlarge the aperture of taphole. Ensure 150~180 minute/time, reasonable times should be 8~10 time/day. Lighten labour intensity, decrease the consumption of raw material and at the end reduce the cost.