Blast-furnace

In the iron and steel industry, PRG carries on dry and shotcrete installation inside:

• Blast furnace stacks
• Hot blast stove outlets
• Hot blast mains with compensators
• Gas offtakes
• Cyclones
• Scrubbers
• Dustcatchers
• Iron and steelrunners…

PRG creates customised tools to achieve quality repairs in reduced time while always although ensuring maximum safety for its staff.

Some examples of important repair that PRG can carry out successfully:

• A manual solution

Skilled specialists operate in hot conditions inside the blast furnace stack. The use of our job-specific platforms is among others the key to this kind of operation.

1. Stopping the blast furnace and lowering the burden
2. Opening the existing doors and probe holes located in the top
3. Levelling of the burden
4. Gunning of the insulating plug
5. Introduction and erection of the light foldable PRG platform
6. Thorough cleaning of the walls
7. Gunning
8. Evacuation of rebound
9. Breaking up the insulating plug
10. Remove the mobile platform
11. Closing doors and openings

• A solution by gunning/shotcrete robots
   

Especially designed for emergency interventions and where the quantities to be installed are insignificant , to extend the life of your plant, our robots are available for all kind of operations :
 

1. Stopping the blast furnace and lowering the burden
2. Opening of both doors (for the introduction of the robot) and probe holes located in the top (for fixing of the robot)
3. Gunning of the insulating plug
4. Assembly of the Giro Gun robot
5. Cleaning of the walls
6. Gunning
7. Dismantling of the Giro Gun robot outside the blast furnace
8. Demolition of the insulating plug
9. Closing of both doors and the openings
    

Nevertheless, our experience leads us to favour the manual solution compared with the robot for the quality of the final result. Mainly for following reasons :

• Installation work (gunning) of better quality (mechanical strength..) : the distance between the gunning hose and the wall is correct (maximum 50 cm for shotcreting),the thickness applied is a development up to 1 m (that the robot cannot do; in addition, it cannot maintain a consistent distance between the wall and the nozzle). Moreover, we are certain that there will no « gaps » between the existing lining and the new one. By robot, we don’t have the same freedom of movement or control. Often, the importance of the quality and the experience of the gunner are underestimated.
   
• Better adherence: the area to be repaired is clean and stable, especially when one must go down into the blast furnace bosh. By robot, we can only carry out a superficial cleaning of the walls by a light sandblasting and therefore cannot ensure their cleanliness.
   
• Higher productivity : when the floor is installed and the gunning phase begins, we can work with several machines in parallel. This is not possible by robot.
   
• Lower percentage of rebound : the distance is correct between the nozzle and the wall (Cannot be done with robot).
   
• Effectiveness for the breaking of the insulating concrete slab : we can even in some additional hours, remove the rebound to ensure being able to restart the furnace and avoid any blocking.
   
• Easier replacement of cooling plates : we can intervene from the inside in parallel with the mechanics outside the blast furnace.

We operate also in storage hoppers (storage system/silos/bunkers) of prepared raw materials supplying the blast furnace.

The 3 stages of resurfacing of a silo lining

1. Before the entrance of specialists in the silo, cleaning of walls using a specific robot for the cleaning of tanks to work safely.
    
2. More detailed cleaning in the area where we must intervene, and possibly welding of worn metallic bars or their replacement.
    
3. Application by gunning of an abrasive resistant concrete from a platform designed especially for this purpose.