Urgent repair of a flat glass furnace with Repair Hot Bottom AZS solution


SEFPRO Care had to deliver 43 tons of Repair Hot Bottom AZS product to a customer who had diagnosed a highly worn floor in their flat glass furnace. The bottom area of a glass furnace is a crucial and fundamental part of its structure that must not be overlooked. The slightest defect can indeed compromise a whole part of the production. A good repair is therefore essential to help the customer achieve better results and greater efficiency. The Repair Hot Bottom AZS solution is widely considered the most effective product available for reducing production downtime and extending the lifespan of glass furnaces due to its unique properties.


Checking for wear and tear in glass furnaces can be challenging. The customer detected very advanced areas of corrosion in the bottom of their glass furnace, which has led to an urgent repair. This is a major safety risk for the furnace that requires either a shutdown or a hot repair. The customer wanted to avoid a shutdown of the glass furnace, so he considered the possibility of repairing it with the Repair Hot Bottom AZS solution.


SEFPRO Care was therefore contacted to provide this monolithic solution and helped to supervise the installation. The repair was carried out by a company specialized in this type of installation. By using this versatile solution, the Repair Hot Bottom AZS solution proved its worth during the repair of the highly worn floor. The solution was applied without taking the furnace down cold. Only a draining was performed, followed by a casting at nearly 1,300°C (2,372°F).

The furnace was able to return to production at a faster rate, and without having a long and dangerous hold at very high temperature, which could lead to structural deformations and damages. In comparison to a classical bottom repair material under the same repair conditions, our customer was able to save four days during the repair process.


four days saved during the repair process


Here are the main characteristics of a Repair Hot Bottom AZS product installation:

  1. Minimum time glass to glass: this monolithic solution made of fused cast AZS grains can be installed at high temperature. It exhibits good compactness and very strong resistance to glass corrosion.
  2. Drilling compatible: the product’s high mechanical resistance facilitates drilling for the installation of new electrodes.
  3. Low sintering temperature: product designed to sinter at 1,200°C - 1,350°C (2,192°F - 2,462°F) to prevent a risky heat up at higher temperature.


  1. Quick return to full production
  2. Four days saved during the repair process
  3. Furnace preservation during repair
  4. Safe electrode installation
  5. High corrosion resistance
  6. Furnace lifespan extended


Solution: Repair Hot Bottom AZS

Markets: container, flat, insulation

Area: glass furnace bottom

Temperature application: 1,290°C (2,354°F)

Material: 1 product to be mixed with water

Installation method: pumpable with water-cooled lance

Main composition: 29.3% ZrO2, 51.1% Al2O3

Technical details:

  • 25 kg bag
  • Open porosity: 17%
  • Bulk density: 2.64T/m(165 pcf)
  • Setting type: heat set