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. 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.