Applying High Performance Refractory Castables by Gunning

Sep 16, 2023

Gunning techniques allow fast, efficient application of monolithic refractory castables to create durable protective linings. Compared to forming and firing bricks, gunning castables can rapidly install refractory surfaces with minimal joints and seams. This continuous, homogenous application better withstands thermal shock, abrasion, and corrosion common in high temperature environments. For optimal results, pairing high quality gunning and insulating castable materials with proper gunning equipment and methods is key.

Gunning castable

An Introduction to Gunning Refractory Castables

Gunning castables are monolithic (single mass) materials installed via pneumatic gunning to form a dense refractory barrier. Key properties include:

  • High alumina or alkaline earth content able to withstand temperatures exceeding 2500°F
  • Hydraulic setting from added water activates bonding agents
  • Low concrete slump values for thick application without formwork
  • High adhesive strength and abrasion resistance
  • Low porosity and permeability

When gunned into place, castables cure into a seamless, monolithic lining resistant to spalling and mechanical damage.

Benefits of Gunning Refractory Lining Installation

  • Extremely rapid installation of large refractory surfaces
  • Minimal construction joints compared to brick for improved thermal shock resistance
  • Strong bonding to substrates with enhanced sealing ability
  • Can fill complex geometries and service deeply worn surfaces
  • Lower labor costs compared to forming and firing refractory bricks
  • Minimal setup required compared to bricklaying
  • Gunning enables rapid, high performance refractory linings in demanding environments.

Specialized Unshaped Refractory Materials Insulating Castable

While standard castables resist high temps and corrosion, insulating castables provide additional benefits:

  • Very low thermal conductivity to reduce heat losses
  • Contains lightweight, low density aggregates to generate porosity
  • Excellent insulation value with moderate strength
  • Withstands thermal gradients and cyclic heating conditions
  • Typically fiber-reinforced to increase strength

Insulating castables gunned as a backing layer improve energy efficiency and protect substrates.

Achieving Quality Results with Proper Installation

To maximize performance, it is critical to:

  • Use top quality castable materials from proven, trusted suppliers
  • Select suitable gunning equipment for material volumes and site access
  • Employ experienced crews for prep, installation, and curing
  • Follow all mixing and application specifications from the manufacturer
  • Cure castables using proper techniques to develop strength
  • Inspect for defects and test lining thickness and bonding

Contact refractory experts to review needs and develop an optimized gunning solution.

Gunning Refractories for Reliable Protection

From furnaces to boilers, gunning high performance castables creates durable, heat-resistant linings with rapid installation. Combining specially formulated gunning and insulating refractory materials with proper gunning equipment and techniques allows industrial facilities to cost-effectively enhance safety and efficiency.