The steel structure workshop possesses lots of advantages such as pretty appearance, bright colors, diversified building types, low cost, short construction period, highly industrialized production, easy installation and construction, flexible layout, and obtains the benefits of recyclable, light weight, uniform material, easy to design and convenient to calculate. The steel structure building has been increasingly used in modern industrial plants. But there is a shortcoming of steel structure workshop, that is non-fireproof.
Although steel is non-combustible material, under the action of high temperature in an open flame, its mechanical index will change greatly as the temperature increases, and the bearing capacity and balance stability will decrease greatly with the increase of temperature. The decrease will be more obvious at about 500 degrees Celsius, and it usually collapses due to the loss of load-bearing capacity in about 15 minutes.
This article will share three fire protection measures of industrial steel workshop, which make sure that they will not exceed the critical temperature quickly when the fire temperature rises. The steel structure should also ensure stability in the fire within a specified time and protect the safety of personnel and property. Now let’s talk about these three measures in detail.
Since the steel part itself cannot reach the required fire resistance limit, it is necessary to take corresponding fire protection measures for them. Commonly used fire protection measures include fire retardant coating method, foam fire-retardant coating method and external fire-retardant layer method.
1.Fire Retardant Coating Method
Fire retardant coating method is to spray fireproof coating on steel structure to improve its fire resistance limit. At present, fireproof coatings for steel structures are mainly divided into two types: thin coating type( B type, including ultra-thin type) and thick coating type( H type).The thin coating thickness is less than 7mm, which can absorb heat and expand and foam during a fire to form a foamed carbonized insulation layer, thereby preventing heat transferred to the steel structure, delaying the rise of steel structure’s temperature, and playing a role in fire protection.
Picture 1: fire retardant coating is foaming under the fire
It owns the main advantages of thin coating, light load on the steel structure, and good decoration. It is easier to paint on the steel structure surface with small area and complex shape than the thick type. The thickness of the thick type coating is 8-50mm, and couldn’t foam when heated. It relies on its lower thermal conductivity to delay the rise of steel structure temperature, thus playing a role in fire protection.Both of them have different performance characteristics and are suitable for different occasions.
2.Foam Fire-retardant Coating Method
Foam fire retardant coating is a kind of flame retardant paint made of various materials such as film forming agent, flame retardant, foaming agent and etc. Fire retardant coating has the same physical properties compared with general paint. The difference is that the paint film itself is not easy to burn after it is dried, and it can postpone the flame to the painted inflammable goods in fire, Fire retardant coating possesses feature of fire resistance.
According to the test: the general coating and the fireproof coating are painted to the wooden board separately and wait them drying, then bake them with same flame. The wooden board painted with the general coating is scorched with the paint together in less than 2 minutes. The one painted with non-expandable fire-retardant coating only smoldered after 2 minutes, and immediately extinguished after standing for 30 seconds. For the wood board painted with expandable fire-retardant coating, it even didn’t appear smoldering performance after baking for 15 minutes. It can be seen that the use of fire-resistant coating on the goods surface can prevent the fire from spreading and protect the goods surface in a certain time, thus to gain precious time for fire fighting.
Picture 2: foaming fire retardant coating under the fire
3.External Fire-retardant Layer Method
The external fire-retardant layer method is to add an outer layer on the external surface of the steel structure, which can be cast-in-place or sprayed. The cast-in-place solid concrete outer cladding is usually reinforced with steel wire mesh or steel bars to limit shrinkage cracks and ensure the strength of the outer shell. The spraying method can form a protective layer through spraying lime cement or gypsum mortar on the steel structure surface at the construction site , or it can be mixed with perlite or asbestos.
At the same time, the outer cladding can also use prefabricated plates made of perlite, asbestos, gypsum or asbestos cement and light concrete, which could be fixed on the steel structure with adhesives, nails, and bolts.
Picture 3: fire retardant panel
Safety is the most important thing in life and production, hope this article will be helpful for you. Thanks for your reading.