Q:How long is the fire endurance of the rock wool board?

In the fire?safety?rules, of the building materials are classified as non-burning combustion body, difficult to burn the body and burning body categories depending on its difficulty level of burning. Rock wool board is the fiber processed by the coated steel sheet and basalt minerals and other inorganic minerals,and the building panels through artificial composition. Because that the dominant sectors, like, steel plate and rock wool are non-combustible materials, so it should be considered as non-combustible?component. The fire resistance of rock wool board has its judging criteria. Loss of support capacity, loss of integrity and loss fire insulation function. Its fire resistance is within 2 hours.

Q:Which one is better, fire-resistant wood or steel?

According to my understanding. This fire-resisting wood is better. Iron birch. The iron birch is three times harder than the oak, twice as hard than ordinary steel. It is the world's hardest wood which is used as a substitute for metal. The Soviet Union have used iron birch for the manufacturing of roller ball, bearings and it is applied in yachts. Iron birch has some wonderful characteristics. Since it has very dense texture, once put in the water it will sink; even if it is soaked in the water for a long time, the inside still remains dry. The iron birch is twice harder than the steel, it doesn't mean that its hrc value is twice of that of the steel. HRC means test load 1471.1N (150KG-F) using a diamond cone head with the point angle of 120 degrees to press. The calculation formula HR= (K-H) /C,K=0.2MM,H is the depth of indentation after releasing the major load. C= 0.002MM, so HRC100 is a limit value, then H is 0, which means that even the diamond will not drill into it. Generally the hardness of bearing steel is about HRC60. Iron birch is the championship among trees in terms of hardness. The bullet hit the wood is like hitting on a thick steel plate and the wood will be motionless. So, it is known as a tree harder than steel. I hope my answer will be helpful to you.

Q:What is the fireproofing requirements of external wall thermal insulation materials?

According to the "building external wall insulation fire barrier zone technical regulations" to be published: it is not less than the level B2. But before the procedure was published, it should be strictly implemented the document, level A is the best, I hope to help you, hope to adopt

Q:Who knows the refractoriness of high temperature lightweight firebricks?

pores of high temperature lightweight refractory bricks is made by lightweight aggregate such as combustibles, foaming?agent, and hollow?sphere production with better thermodynamic stability. Refractoriness reaching 1200 ℃ or more is first grade refractories. fire resistance of building blocks of 100mm thick can reach 225 minutes, 200mm thick brick 480 minutes.

Q:What refractories are accessible with ease in daily life? This material is suitable as a disposable mold and crucible for melting brass.

Well, you have no furnace to cast disposable molds. You can sieve sand which is used for blending cement with siever (left the most fine behind)! And then you can go to hardware (parts) factories directly with molds to ask them to pour. Remember that brass (60 copper) needs to be heated to 1200 ℃, while the crucible is not needed.

Q:How to divide the fire resistant level of construction thermal insulation materials?

Combining three versions of GB8624 (1997,2006,2011), external wall thermal insulation fire?rating can be basically divided into: A1, A2, B1, B2, B3 and other levels. There are many technical indexes for specific division. And it is mainly determined in accordance with the national standard GB8624 Building materials combustion levels.

Q:How to understand qualitative and qualitative refractory materials?

Such as amorphous refractory castable, referred to as bulk loading, cast material, ramming material, refractory clay etc., utensils and other special products. Amorphous refractory material products, refractory heat insulating bricks and experimental and industrial crucible, spraying materials, such as burning bricks, electric melting brick, turn it into required shape and process heat treatment in where it is used.

Q:What are the models of bauxite with high alumina?

China Ferrous Metal Industry Corporation released the industry standard of bauxite (YS / T78-94) in 1994. According to this standard, bauxite can be divided to sedimentary diaspore, stacked type diaspore and lateritic gibbsite. According to the chemical composition, it can be divided into nine trade marks as LK12-70, LK8-65, LK5- 60, LK3-53, LK15-60, LK11-55, LK8-50, LK7-50 and LK3-40. In addition to the provisions of chemical composition of bauxite, the standard also requires that the water of sedimentary diaspore shall not exceed 7% and water of stacked type diaspore and lateritic gibbsite shall not exceed 8%. Moreover, particle size of bauxite should be not greater than 150mm. Bauxite shall not be mixed with clay, limestone and other debris.

Q:What's the material of fireproof and wear-resisting floor?

1. It is the kind of special concrete floor, and its production process is the same with that of the common concrete floor, but it uses different material which needs to be the pebbles and sand after processing with marbles and dolomite. 2. Fireproof floor is a kind of decorative material which is laid on the ground of the factory or large areas of floors. It does not support combustion or it is composed of flame retardant materials. Fireproof floor has two categories. One is composed of aggregate wear-resistant material which is solid particulate matter. Its construction method is to evenly spread aggregate wear-resistant particles on the surface layer of the concrete when the floor is just pouring concrete and solidified, and then a firm flame retardant layer will be formed on the surface layer. This is the the so-called carborundum wear-resisting floor. But this kind of material has many limitations and can only be used on the surface of the just poured concrete. In addition, it is easy to fade in color and not beautiful in appearance. So this is not fireproof floor in the strict sense. Here we focus on a new liquid coating fire protection floor, which is environment friendly, widely used and beautiful in appearance. 3. Wear-resistant floor has the characteristics of pressure resistance, strong wear resistance,oil resistance, and anti-infiltration. It is also dust-free and easy to clean. After entering the initial setting of concrete, construction can be started immediately. Construction period is usually longer, but better using effect will arise.

Q:can slag tailings be used to be the base materials of refractory materials ?

perhaps not, because it has many pores.