Q235 steel plate: a comprehensive guide from material selection to application

On construction sites, we often see orange-yellow tower cranes and silver-gray Steel Frames. Many of the "skeletons" of these behemoths are made ofQ235 steel plates.

As one of the carbon Structural Steels with the longest application history in my country, Q235 has accompanied China's construction industry through more than half a century of ups and downs.

Today, let us get to know this "old ox" in the "steel family".

1. Simple but powerful
Speaking of the characteristics of Q235, the four words "economical and practical" are more appropriate. The yield strength of this steel is just 235 MPa (this is also the origin of its name).

Although it is not as good as those high-end alloy steels that easily reach thousands of MPa, it is more affordable and easy to process.

"Just like you can't use all mahogany furniture when building a house," said Mr. Li, who has been engaged in steel structure design for 20 years.

"Q235 is the pine wood in the construction industry. It is sufficient, easy to use and durable." Indeed, this kind of steel is not only not easy to crack when welded, but can also be easily bent into various shapes,

which is particularly suitable for making building templates, steel frames and other components.

2. Model selection is particular
Although they are all called Q235 steel plates., they are subdivided into four grades: A, B, C, and D. This is like the same brand of car has different configuration versions:

Grade A is like the "basic version", suitable for occasions with low performance requirements;

Grade B is the "standard version", which is most common in construction sites;

Grade C and D are "Northern Special Edition", which can maintain toughness in low temperature environments.

It is worth noting that some steels are marked with the words "Q235BF", where "F" stands for boiling steel. This kind of steel will produce bubbles when cast, just like the bubbles in Coke.

Although the cost is low, the quality is slightly inferior. In contrast, the calm steel marked with "Z" is more dense and durable.

3. The ubiquitous "steel guard"
You can find Q235 in any construction site:

Steel springboards under the feet of workers

Temporary construction fences

Formwork support for concrete pouring

Auxiliary structural parts of tower cranes

"We have done statistics," said Manager Zhang of a building materials market, "In an ordinary real estate construction site, the use of Q235 steel plates can account for more than 60% of the total steel."

In addition to the construction field, this steel is also widely used in the production of shelves, billboards, simple factories, etc.

4. Tips for use
Although  Q235 steel plates. is very "tough", you still need to pay attention to the following when using it:

Rust prevention should be done in humid environments

It is recommended to use Class B or above for important load-bearing structures

Pay attention to controlling the current during welding

Grade C/D is preferred in low temperature environments

"Although there are many new materials now," said Professor Wang, a steel structure expert, "Q235 steel plates is like a white shirt and will never go out of style. The key is to use it in the right place."

Conclusion 
From high-rise buildings to bridges across rivers, Q235 steel plates have witnessed the miracles built by China with their solidity and reliability. In this era of pursuing high-tech materials,

we still have to praise such "basic skills". After all, the rise of a towering building is inseparable from these silently dedicated "steel backbones".