This text introduces the domestic development state of the tapping hole clay,the corrosive mechanism about the tap hole,the raw material and its production craft flow,the development of the tapping hole clay and the technical progress of Baotou Steel Corp.

The process of recovery of refractories for ladle and the application of recovery material in blast furnace tap hole clay are introduced emphatically.

The application of BG-75 hydraulic clay gun is expounded through the description of the technical improvement of the hydraulic clay gun for No.

This paper introduces the diagnosing and treating measures of fault consisted of the fail of turning gear of turning gun and not meeting the requirement of design for blocking taphole time at operation of turning gun,etc,combined with the technical charatcers and mechanismic analysis of SGXP 240 clay gun in the ironmaking plant of Laiwu iron and steel group Co.

This article focuses on the analysis of line motion mechanism of two motion clay gun for blast furnace.

Based on the production experience and the analysis on the aspects of iron notch depth,notch opening situation and slag tapping from the iron notch,the reasonable composition of gun mud is found out to improve its quality,and as a result,the iron tapping from the notch gets obvious improved.

The development and application of refractories used in iron runner,gun mud and hard extruding repairing material is introduced.