Q235B square pipe is one of the products with increasing demand, especially in the fields of petroleum, chemical, power generation, automobile, shipbuilding, construction and environmental protection. The annual consumption is about 700,000 tonnes. Domestic Q235B square pipes have covered the variety specifications of the world's standards, and the specifications and varieties of shaped pipes are more than a hundred kinds. Next, we will discuss the differences between hot rolled and cold rolled Q235B square tube:

1, Cold-rolled structural steel allows for local buckling, thus better utilizing its load-bearing capacity, whereas hot-rolled structural steel does not permit local buckling of the cross-section.

2, Hot rolled steel and cold rolled steel residual stresses of different reasons, so they are also very different distribution of the cross-section. Cold-formed thin-walled steel section on the distribution of residual stress is curved, and hot-rolled steel or welded steel section on the residual stress is thin film.

3, The free torsional stiffness of hot rolled steel sections is higher than that of cold rolled steel sections, so its torsional performance is also better.