Furnace Refractory Structure Auditing

After the completion of a furnace construction, it is important to monitor the condition of the furnace refractory structure on a scheduled basis over the total furnace campaign period. This monitoring provides a pro-active approach towards identifying potential problem areas of the furnace refractory structure for both the immediate time and the future, therefore, minimising the possibility of major structural problems or catastrophes occurring and extending the designed furnace campaign life. DISMATEC supply a total audit package carried out by qualified and experienced engineers to meet the customers’ requirements, including;

• Visual audit: A full visual audit of the total furnace refractory structure is carried out. This notes the actual condition of all areas of the furnace refractory structure, against this information recommendations are given to either monitor or work on a particular area. An endorsement to the visual audit is the recording of refractory outside face temperatures at selected positions, these being trended over the furnace campaign life. In parallel with the refractory structure visual audit observation of the supporting steelwork structure is made in order to determine possible heat attack positions, deformation and strength loss.
  
• Thermography audit: DISMATECs’ thermography audit predominately focuses on the glass bath sides and bottom together with the throat areas, although other areas of the furnace can be added, including the melting end crown, superstructures and other selected areas to indicate varying temperature patterns.
  
• Endoscopy audit: DISMATECs’ endoscopy audit predominately focuses on the internal area of the melting end together with other selected areas that may be giving cause for concern. Images of the internal area are taken and recorded to be observed to provide an assessment of the furnace refractory structure internal area and identification of anomalies that may give cause to an external adverse condition in the future.
  

Each audit category has its’ own individual merits to identifying potential problem areas and together form the basis of a comprehensive report provided by DISMATEC after each audit is completed.
The report includes for all observations made, recommended action points, identification of immediate problems, identification of potential problems and structure condition executive summary.
It is extremely important that any action points and work description recommended in the audit report is fully understood, work is carried out to correct procedures and standards. To ensure that this is achieved DISMATECs’ presence throughout any planning and work execution phases is paramount and ultimately providing the workforce to carry out recommended work or at the very least providing supervision of a local workforce.
Audit frequency
Over the period of a furnace campaign life an audit frequency is identified by DISMATEC for each year of the furnace campaign, with the number of auditing periods generally increasing as the campaign period increases and degradation of the furnace refractory structure occurs.
DISMATECs’ furnace refractory structure audit service is a means to achieving an extended furnace campaign life and protection of assets by providing a complete “health check” of the structure and exact condition status as the furnace campaign life continues.
DISMATEC recommend that the first audit including for the total auditing service be carried out after 10-12 months after start-up. This audit service is termed the ‘Benchmark’ audit with the results acting as a reference point and comparison status against future audits.