Detailed introduction and use of rock wool
Detailed introduction and use of rock wool
Author: Nanjing Hai insulation Time: February 20, 2021
1. What is mineral wool
Mineral wool is a general term for cotton-like fibers made of molten rock, slag (industrial waste), glass, metal oxide or ceramic soil. Common mineral wool includes slag wool, rock wool, glass wool, aluminum silicate refractory fiber and other varieties.
2. What is mineral wool
The standard name of mineral wool is slag wool. Slag wool is an inorganic fiber made from industrial slag, such as blast furnace slag, phosphorous slag, and fly ash as the main raw material, after remelting and fiberizing. After processing, it can be made into various products such as boards, tubes, felts, belts, papers, etc. It should be used for heat insulation, fire prevention, sound absorption, earthquake resistance, etc. of construction and industrial equipment, pipelines, and furnaces.
3. What is rock wool?
Rock wool is a kind of mineral wool. Rock wool is a fluffy short-fiber cotton made of natural rocks such as basalt, diabase, dolomite, iron ore, bauxite, etc. as the main raw material by high-strength temperature injection. After processing, it can be made into various products such as boards, tubes, felts, belts, papers, etc. It should be used for heat insulation, fire prevention, sound absorption, earthquake resistance, etc. of construction and industrial equipment, pipelines, and furnaces.
What is the difference between mineral wool and rock wool?
(1) Similarities
a. They are all fibrous heat-insulating products made by centrifugation at high temperature;
b. The same product standard "Rock wool, slag wool and their products GB/T11835-2007 for thermal insulation" shall be implemented in the industrial field;
c. In the construction field, the same product standard (except for external wall insulation) "Rock wool and slag wool insulation products for construction" GB/T19686-2005 is implemented.
(2) Difference
a. Different raw materials: rock wool uses natural ores such as basalt (or diabase) as the main raw material; mineral wool uses industrial waste slag such as blast furnace slag as the main raw material;
b. The fiber mechanical properties, temperature resistance and chemical stability of rock wool are better than those of mineral wool;
c. Mineral wool contains more alkaline compounds, and its volume stability and water resistance in a humid environment are worse than rock wool;
d. The acidity coefficient of mineral wool is lower than that of rock wool, and it is worse than rock wool in terms of weather resistance and service life;
e. The use temperature of mineral wool fiber is lower than rock wool, and it is worse than rock wool in terms of high temperature volume stability.
What does the acidity index of rock wool mean?
The acidity coefficient is a measure of the chemical durability of rock wool. It is the mass ratio of the sum of silica and alumina to the sum of calcium oxide and magnesium oxide in the fiber composition. The acidity coefficient is an important index to evaluate the quality of rock wool products. The acidity coefficient is high, the weather resistance is good and the life is long. At the same time, the acidity coefficient is also an important means to distinguish between rock wool and slag wool. The raw material of slag wool is based on slag and the acidity coefficient is less than 1.5, and the raw material of rock wool is based on basalt, and the acidity coefficient is ≥ 1.6.
How are rock wool products produced? What are its characteristics?
A good rock wool product is made of selected basalt as the main raw material. The rock is melted at high temperature (temperature greater than 1450℃). After the inorganic fiber is made by high-speed centrifugal equipment, special binder and dustproof oil are added, and then passed through the drum. It is a new type of lightweight thermal insulation material made by laying felt on the cotton swing belt, and changing the fiber arrangement through special equipment to arrange the rock wool fibers into a three-dimensional chaotic structure, and finally curing and shaping equipment. Then, according to different purposes, products such as rock wool board, rock wool felt, rock wool tube shell and so on are made.
Its characteristics are:
(1) Good thermal insulation performance.
(2) Excellent fire resistance.
(3) Excellent sound insulation performance.
(4) Long-lasting chemical stability.
Where can rock mineral wool products be applied?
(1) The application of rock and mineral wool products in construction: used for heat preservation and sound insulation of building walls and roofs, fire protection and noise reduction of building partitions, firewalls, various sandwich panels, fire doors and elevator shafts.
(2) The application of rock and mineral wool products in industry: heat insulation, fire prevention, sound absorption and earthquake resistance of industrial equipment, pipelines, containers and various kilns.
(3) Application of rock and mineral wool products in shipbuilding industry.
(4) The application of rock and mineral wool products in other fields: instead of alkali-resistant glass fiber weaving high-performance alkali-resistant grid cloth, used for heat preservation and fire protection of vehicles, mobile equipment, cold storage projects, and air-conditioning pipelines.
Make friction materials and sealing materials.
The difference between rock wool and insulation wool/glass wool?
Rock wool and glass wool have many similarities. They are both commonly used heat-insulating and sound-absorbing materials in industry and construction. They can even be used instead under certain conditions, but they also have some obvious differences:
1. Different production materials and processes
Glass wool is made by melting the raw material and flowing through the leakage plate into the centrifuge. Under the high temperature of centrifugation, the fiber attached to the resin binder settles on the moving mesh belt, and is processed in a constant temperature curing oven. Rock wool board products are made of minerals ( Mainly basalt, etc.) are melted, centrifuged and fiberized, added with additional materials and processed, and finally solidified and shaped.
2. Different product performance
Glass wool has lower bulk density, less slag ball content, lower thermal conductivity, longer service life, and greater fiber toughness than rock wool. However, the maximum use temperature of rock wool is about 600 degrees Celsius, and glass wool is only about 260 degrees Celsius. At the same time, glass wool has a certain degree of flexibility and can often be rolled into felt, while rock wool is relatively "rigid" and often in the form of plates, which determines the different laying, installation and fixing methods when they are used.
3. Different product uses
Glass wool is generally used for heat preservation parts below 200 degrees Celsius, and is mostly used for heat preservation of general buildings or low-temperature pipelines. Rock wool is generally used for heat preservation parts with a temperature of 500 degrees Celsius, and is mostly used for heat preservation of high-temperature thermal pipelines or power equipment.
4. Different product weights
The mechanical strength of rock wool is greater than that of glass wool, and the density of glass wool is less than that of rock wool.