The hot wind pipes adopts a working layer lining brick with excellent quality and appropriate masonry structure, combined with lightweight insulation bricks with high temperature resistance, it can guarantee the service life of more than 16 years.

However, the cracking and spalling of the brick lining from the sanchakou is a weak link that affects the long-term operation of the hot air pipe, and so is the top inside the pipe.

Frequent occurrences of hot wind pipes accidents, in addition to the improper use of brick lining materials in hot wind pipes, the introduction of counterfeit products and masonry problems at low prices, but also related to factors such as zinc and alkali metals contained in hot air gases.

The brick lining on the inner surface of the pipe will also appear loose and peeling due to chemical reaction with zinc and alkali metals.

In order to improve the service life of the hot wind pipes of the iron making system, it is possible to establish a suitable standard for hot wind pipes refractory materials, to prevent low-price bidding, and to deal with the problem of zinc enrichment and alkali metal local enrichment in the gas inside the pipeline.

These are all beneficial to improve the service life of the hot wind pipes and maintain the stable operation of the blast furnace iron making.