Mechanism and Detection Methods of Thermal Stress-induced Cracks in Refractory Bricks | Practical Guide for Chemical Equipment Maintenance

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2025-10-16

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This article delves into the common issue of cracking in refractory bricks within chemical furnaces, focusing on revealing the structural damage mechanism caused by thermal stress, including the impacts of sudden temperature changes, uneven heating, and internal material defects. It scientifically explains how high-strength refractory clay insulation bricks produced with hollow sphere structures and high-grade clay materials enhance thermal shock resistance. Alongside, it provides key points for daily inspections, early damage identification, and maintenance suggestions to assist chemical equipment maintenance personnel and technical teams in effectively preventing thermal stress damage and ensuring the safe and stable operation of equipment. The article is accompanied by graphical analyses and typical cases, combining technical depth with practicality to help readers comprehensively master refractory brick maintenance skills and improve production efficiency.

Mechanism and Detection Methods of Cracks in Refractory Bricks Caused by Thermal Stress: A Practical Guide for Chemical Equipment Maintenance

This article delves into the common problem of cracking in refractory bricks inside chemical furnaces. It focuses on revealing the structural damage mechanism caused by thermal stress, including the impacts of sudden temperature changes, uneven heating, and internal defects in the materials. Let's first understand the severity of the cracking problem in refractory bricks.

The Severity of Refractory Brick Cracking

Cracking in refractory bricks is a widespread issue in chemical furnaces. These cracks can significantly impact the safety and economy of equipment operation. According to industry statistics, nearly 70% of equipment failures in chemical furnaces are related to refractory brick problems. When refractory bricks crack, it not only affects the thermal insulation performance of the furnace but also may lead to safety hazards such as heat leakage and even equipment damage. This directly increases the maintenance cost and downtime of the equipment, causing substantial economic losses to enterprises.

$The cracking phenomenon of refractory bricks in a chemical furnace$

Mechanism of Thermal Stress - Induced Structural Damage

Thermal stress is the main culprit behind refractory brick cracking. Sudden temperature changes, such as rapid heating or cooling during furnace start - up or shutdown, can generate large thermal stress within the bricks. Uneven heating also plays a role. For example, in some areas of the furnace where heat distribution is uneven, the temperature difference between different parts of the refractory brick can reach up to 200 - 300°C, causing uneven expansion and contraction and leading to cracks. Additionally, internal defects in the materials, such as pores and micro - cracks, can act as stress concentration points, accelerating the cracking process under thermal stress.

Enhancing Thermal Shock Resistance with Special Materials

High - strength refractory clay insulation bricks produced with a hollow - sphere structure and advanced clay materials can effectively improve thermal shock resistance. The hollow - sphere structure provides good thermal insulation and can absorb and disperse thermal stress. Advanced clay materials have excellent high - temperature stability and mechanical properties. Tests show that these high - strength refractory clay insulation bricks can withstand temperature changes of up to 500 - 600°C without significant cracking, which is much better than ordinary refractory bricks.

$The structure of high - strength refractory clay insulation bricks$

Practical Maintenance Guide

Regular maintenance is crucial for preventing thermal stress damage to refractory bricks. Here are some key points:

Daily Inspection: Check the surface of refractory bricks regularly for cracks, peeling, or other visible damage. This should be done at least once a week.
Early Crack Identification: Use non - destructive testing methods, such as ultrasonic testing, to detect early - stage cracks that are not visible to the naked eye. This can be carried out once a month.
Maintenance Strategies: For small cracks, repair materials can be used for filling. For severe cracks, the damaged bricks should be replaced in time.

Typical Cases

A chemical plant was facing frequent furnace shutdowns due to refractory brick cracking. After replacing the original ordinary refractory bricks with high - strength refractory clay insulation bricks and implementing a regular maintenance plan, the frequency of furnace failures decreased by 80%, and the service life of the furnace was extended by more than 2 years. This case clearly demonstrates the effectiveness of using high - quality refractory bricks and proper maintenance.

$The comparison of a furnace before and after using high - strength refractory clay insulation bricks$

In conclusion, understanding the mechanism of thermal stress - induced cracking in refractory bricks and adopting effective prevention and maintenance measures are essential for ensuring the safe and stable operation of chemical equipment. If you want to learn more about the advantages of high - strength refractory clay insulation bricks and how they can improve the performance of your chemical furnaces, click here to explore further.