Right Use of Refractory Mortar

Proper Use of Refractory Mortar

The use of refractory mortar in the construction of masonry kiln flues, kiln tunnels, kiln walls, and fireboxes has significantly aided us in lowering the cost of masonry kilns. Linings can be added as a protective coating by smearing or spraying refractory mortar, also known as fire brick mortar.

Refractory Mortar is commonly used in coke ovens, blast furnace hot air furnaces, glass furnaces, and other industrial furnaces due to its excellent thermal exfoliation. At the same time, since almost all refractory raw materials can be ground into a powder and used to make high-temperature mortar, they can be used as refractory brick joint material. That’s why it’s known as fire brick mortar. Refractory mortar is used in places where refractory bricks are needed. As a result, Refractory Mortar is commonly used in thermal engineering equipment in industries such as metallurgy, construction materials, machinery, petrochemicals, glass, boilers, electricity, steel, cement, and others industries.

Difficulties associated with the use of refractory mortar

Due to the various refractory bricks and the various working conditions of different kilns, the specifications for the use of refractory mortar vary. The refractory lining is prone to failure if not used properly. When making clay refractory mortar, for example, only refractory clay is used without mixing with cement, resulting in a heat-resistant mortar with poor viscosity and strength. Furthermore, due to the high temperature, it loses its binding effect and becomes powdery, allowing the brick body to loosen and the number of bricks to drop frequently.

Masons generally prefer refractory cement and mortar. Why?

You may wonder why masons would prefer factory-made refractory mortar and cement because they are more accessible, safer, and more convenient to use, and readily available. Customers may also expect a high-quality installation from them. The refractory mortar also complies with building codes needed for it to be used in construction. Refractory mortar can withstand extreme temperatures while still being acid-resistant. Because of these characteristics, the material is the most common in refractories.

Types of Refractory Mortar and Their Applications

Hydraulic Setting Mortar

It’s also known as non-water-soluble refractory mortar and is widely regarded as the best refractory mortar available. Hydraulic-setting mortar is a mixture of aggregate and binder that can withstand a temperature of 1499 degrees Fahrenheit for at least 6 hours. Acid resistance, water-insoluble, and the only kind of refractory mortar recommended for setting clay flue liners are just a few of the benefits of non-water-soluble refractory mortar. In terms of workability and curing, hydraulic setting mortar is identical to Portland-based mortar. Furthermore, compared to premixed, it is easier to ship and stock. This kind of refractory mortar is packaged dry and does not need to be separated, hardened, or frozen before use. Finally, it can be used to lay firebrick, set the throat and smoke chamber, install clay flue liners, and use it outside.

Pre-mixed or Air-drying Refractory Mortar

A premixed refractory mortar is a mixture of clays, aggregates, and a binder such as liquid silicate. Such mortar has properties that are inferior to hydraulic setting mortar. For example, after drying, it dissolves in water and takes a long time to dry in a wet environment. Furthermore, efflorescence may be caused by premixed or air-dry mortar. It also comes in ready-to-use pails with the consistency of drywall compound and can be thinned with water. Furthermore, in a hot and dry setting, air drying mortar is preferred because it does not dry out as quickly as other mortar forms. It’s used in the building of kilns and furnaces, among other things.

Worksite Mixed Mortar

Sand, fire clay, Portland cement, and lime are used to make this form of mortar no longer common. This type of mortar can withstand high temperatures, but once it cools, the binder is lost, and it can no longer perform its work. As a result, this form of mortar is not recommended for areas that are frequently exposed to high temperatures.

Tips for the Practical Usage of Refractory Mortar

  • In a high-quality oven, the maximum thickness of refractory mortar is typically 6 mm.
  • If the mortar is thicker than 6 mm, it shrinks, leaving space between the bricks and gradually allowing the bricks to pass.
  • For locations away from the hot face, a mortar thickness of more than 6mm is permitted.
  • Only refractory mortar can be used to keep a brick building solid and secure. It must not be left out in the open on the hot face.
  • Use the relevant code’s recommendation to determine the number of days between the completion of construction and the exposure of the mortar to high temperatures.


Choosing the right refractory mortar for the job is critical, and so is finding professionals you can rely on. The use of refractory mortar and cement necessitates a level of experience that can only be gained through years of practice. Choose your refractory mortar carefully and make sure it meets your requirements. >>Contact us<< now to make price inquiry or for more information. We sell varieties of refractory mortar, visit our >>Product<< page for more detail.



Source : myvigour .com