Application of Abrasion resistant pipe in Dense Medium System

As the medium pipeline is the transmission of high hardness, abrasive strong media suspension, the pressure of the feed cyclone into the tube, in addition to transport media suspension, but also includes coal and gangue. Therefore, compared with the slime mixed pipeline, the media pipe wear speed faster, especially the pressure pipe, such as the cyclone into the material tube, disengage sieve into the material and so on. According to the different materials and flow channels, the general life of the metal pipe material in about a few months to a year or so.

Coal preparation plant site

In recent years, wear-resistant technology and the rapid development of wear-resistant materials, Abrasion resistant pipe technology in addition to metal mines, construction, power plants and other areas of application, in the field of heavy media coal preparation has also been widely promoted, greatly improving the heavy pipe Of the service life, reducing the maintenance workload and material consumption, and promote the rapid development of heavy media coal preparation technology.

Commonly used wear-resistant media tube

Common wear-resistant pipe mainly stone pipe, ceramic wear-resistant pipe, alloy wear-resistant pipe. Cast stone is a natural rock as the main raw material, by ingredients, melting, burning, annealing made of an inorganic non-metallic materials. It has excellent wear resistance, corrosion resistance.

China’s metallurgical, thermal power, mining, chemical building materials and other departments are widely used cast stone materials. The main raw material for the production of cast stone is the broadly distributed basalt and diabase, which are basic magmatic rocks, and the chemical composition is relatively stable. Cast pipe than the alloy tube wear, tough, and has a high corrosion resistance, can be resistant to hydrofluoric acid and overheating of any acid and alkali corrosion. But the cast stone tube density is high, brittle, impatient impact, easy to break, the production process is complex, installation and maintenance is not convenient.

Ceramic wear tube is made of self-propagating high temperature synthesis centrifuge. The seamless steel pipe on the centrifuge tube mold, in the steel pipe by adding iron and aluminum powder mixture. This mixture is called aluminum heat in chemistry. Centrifuge tube mold rotation to a certain speed, the Mars ignited aluminum heat agent, aluminum heat agent immediately burn their own, burning quickly spread, and in the spread of a violent chemical reaction, aluminum heat agent after the reaction of corundum and iron, At the same time release a lot of heat, is the original material in the steel pipe and the reaction after the product, even if the melting point of 2045 ° corundum will all melt, because the reaction is very fast, only a few seconds, the molten reactant in the centrifugal force, Size to be separated. Iron is centrifugal force thrown to the inner wall of steel, Al2O3 is distributed in the inner layer of iron. As the steel pipe quickly heat and heat transfer, Al2O3 and Fe quickly reached the freezing point, and soon stratified solidification. The final formation of ceramic wear-resistant tube from the inside out, respectively, corundum ceramic layer, iron-based transition layer, and the external steel pipe layer. High temperature molten iron liquid.

And the Al2O3 liquid, contact with the inner wall of the steel pipe, so that the inner wall of the steel pipe in the semi-molten state, so that the formation of iron and steel pipe metallurgical structure, iron layer and corundum ceramic layer between the liquid formation of a strong combination of its combined strength (that is, Laminated strength)> 15MPa; ceramic wear-resistant tube crushing strength (that is, from the tube outside the tube when the strength of ceramic crushing)> 350MPa.

Ceramic tile lined pipe & fittings

Ceramic tile lined pipe and the traditional steel pipe, wear-resistant alloy cast steel pipe, cast stone pipe and steel pipe and other essential differences. Ceramic tile lined pipe is a seamless steel pipe, the inner layer is corundum, this corundum is molten state under the action of centrifugal casting. Corundum layer hardness up to HV1200 ~ 1400, it is better than the ordinary combination of corundum grinding wheel performance is much better, can be corundum grinding wheel wear off.

Ceramic tube wear resistance is mainly by the inner layer of a few millimeters thick corundum layer, which wear-resistant alloy cast steel pipe, cast stone pipe both by the composition and organization, but also by the thickness of the anti-wear has been a qualitative leap. The same specifications and unit length of the quality of Ceramic tile lined pipe only wear-resistant alloy steel pipe 1/2, cast pipe 1/3; the cost per meter project reduced by 30% to 40%; so ceramic wear pipe in addition to performance Superior, the project cost also has obvious advantages.

Ceramic tile lined pipe with good thermal shock resistance, this performance in the construction of useful. As the outer layer of steel, coupled with the inner temperature does not crack, in the construction, the flange, purge mouth

And so can be welded, can also be used direct welding method for pipe connection, which wear-resistant alloy cast stone pipe and cast stone pipe in the construction is not easy welding and welding can not be better. In case the production site due to special reasons, ceramic wear tube rupture situation, can be immediately emergency welding to ensure safe production and prevent environmental pollution. It should be noted that the thickness of the ceramic layer in the Ceramic tile lined pipe is not uniform, and it is possible to break out during the transportation, installation, tapping and bending deformation between the two stands, resulting in uneven wear during operation and affecting the use Life, and even cause short-term local steel pipe damage.

Ceramic (Corundum: a-Al2O3) lined abrasion resistant straight pipe and fittings are lined with highly abrasion resistant ceramic by SHS ——-Self-propagating High-temperature Synthetic process.

Ultra-high composite wear-resistant pipe is a combination of internal and external pipe. It is a polymer material as the main material, adding the necessary additives, additives made into wear-resistant inner tube to Q235 steel plate as raw material, coil welded together made of such pipes with high wear resistance, good corrosion resistance (Strength, toughness), impact, play a supporting role, to withstand external pressure, so as to avoid collapse; and to adapt to changes in ambient temperature, light weight, easy to operate processing. Ultra-wear-resistant composite pipe wear resistance, long life, mechanical noise, the use of the product can change the coal preparation plant before the frequent replacement of pipes, downtime for a long time, the amount of maintenance of the situation, that is, improve the efficiency of the coal preparation plant, But also reduce the labor intensity of workers, reducing the maintenance workload. Table 10-16 for the ceramic wear-resistant tube and super-wear-resistant composite pipe technical and economic indicators, for reference.

First of all, in addition to alloy tube, the current commonly used wear-resistant pipe is to rely on a layer of composite wear-resistant materials to improve the life of the pipeline. No matter what the process, wear-resistant layer and the grass-roots bonding strength and then large, is also a combination of heterogeneous materials, can not achieve a seamless. So the installation, especially the welding process requirements are high.

Second, although the hardness of the composite layer is large, but often very brittle, especially ceramic wear-resistant tube, ceramic layer of the impact resistance is relatively poor. Therefore, in the transport, installation, maintenance process should be strictly prohibited to fall, knock, hit, to avoid the composite layer and the base of the separation. For the composite wear-resistant pipe, if the wear-resistant layer after damage, its wear resistance is lost. For example, in the production of blocking, the use of beat the way to clear the block. On the ordinary pipe can be, but by the wear-resistant layer of the pipeline should be strictly prohibited.

In the pipeline installation process, often due to improper welding lead to wear parts of the wear-resistant layer is more or less destroyed, the general impact of the range of about 2 ~ 5mm in the weld, and even may be part of the shedding, resulting in the resistance of the region Grinding down. Therefore, part of the coal preparation plant in the new plant design, often according to the pipeline design drawings, directly to the manufacturer customization, especially the elbow, tee, elbow, distribution and so on. This puts a higher demand on the design of the medium pipe. There are some plants to take into account the design and construction level, often in the first use of the processing can be better general pipeline, after the normal operation of the system, and the system pipeline after the measured, according to the test drawings to the pipeline manufacturer custom wear pipe.
When necessary to be replaced. Old factory transformation can also be used this approach.