Repair Hot Overcoat (HO) ALUMINA: a versatile self-flow concrete based on fused cast Alumina grains, for hot repairs 


Why use Repair HO Alumina in your glass furnace repairs?  

Looking to repair worn refractories in your furnace without causing lengthy production downtime? Shutting down the furnace is not an option for you? With the Repair HO Alumina solution, you can efficiently repair feeders, refiners, superstructures, crowns, and more, without compromising production time. After casting and sintering, the use of electrofused Alumina grains ensures the best possible longevity for the repaired area. 

Repair Hot Overcoat (HO) ALUMINA

Benefits of the Repair HO Alumina solution

This product has been designed to propose a versatile castable solution for hot repairs of glass furnaces. Thanks to its special properties, it can be used in a very broad range of applications and gives the best results in terms of durability. Thanks to its innovative packaging method, the product base can be stored without any time limitation. By using a specific binder, it can be applied as well for Repair CIP Alumina cold installation. Its unique formulation based on fused cast Alumina grains as well as its self-leveling properties guarantee quick repair of blocks in contact with glass and the best corrosion resistance.

  • Easy to prepare and to apply
  • Specifically compatible with the working-end
  • No vibration needed
  • High corrosion resistance

Installation of the Repair HO Alumina solution

This self-flow concrete repair product, based on electro-fused Alumina grains with pumpable and self-flow properties, allows you to efficiently repair glass contact areas of the furnace, specifically the working end.

The repair process typically involves the following steps:

  1. Inspection: A visual inspection is often sufficient to determine the area that needs repair. In some cases, endoscopy can be used if the zone is not visible to the naked eye.
  2. Preparation: Before repairs can begin, the area should be cleaned, and damaged bricks should be removed. If necessary, forms can be installed to contain the product and give the repair its final shape.
  3. Repair Method: Depending on the access and size of the furnace, there are several repair methods that can be employed. The product can be poured with buckets or pumped using single or multi-piston pumps.
  4. Setting: The setting time of the product depends on the temperature of the repair zone and the cold phase of the product. It can vary from a few minutes to one hour. During the setting process, the product should not be covered to allow water removal.
  5. Curing & Restart: Once set, the product can be demolded and, if necessary, reheated up to the operating temperature.

R&D corner

The Repair HO Alumina is an unshaped product dedicated to glass furnace hot repairs. It can be cast in a range of temperatures from 100°C to 1500°C (212°F-2732°F) either in contact with refractories or metallic molds/forms. The self-flowing nature of the product allows for unique repairs in worn, inaccessible, or hollow areas, even under high temperatures.
By mastering the shape, waterproofing, and lubrication of the molds/forms with demolding agents, the casting operators will be able to generate any desired shape by direct casting or pumping.

Repair Hot Overcoat (HO) ALUMINA

Furthermore, thanks to its pure Alumina chemistry and crystallography properties, this product is especially suitable for feeders and refiners hot overcoating operations, superstructure, and glass contact repairs.

  Bulk density Open porosity Green CSS Fired CCS (1400°C/2552°F)
Properties measured on samples 3.1T/m3 15-18% 16 MPa 140 MPa


SEFPRO Care is dedicated to offering glass manufacturers the ultimate solution for improved results and enhanced efficiency in their glass furnaces repair. This high-quality product offers many benefits, such as homogeneous, a low sintering temperature, corrosion resistance thanks to fused cast Alumina grains, and a quick return to production. Repair HO Alumina solution will help extend the furnace lifespan.