Ceramic lined pipe 3 good properties

Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique. 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. A small amount of iron also remains in the ceramic layer. There is a thin equiaxed grain area of alumina near the steel pipe wall, and then alumina was grown in form of dentrite to the surface of ceramic layer.

Why use wear resistant ceramic coatings?

ceramic lined pipe struct section
ceramic lined pipe structure section

Physical Properties of ceramic lined pipe

ceramic lined physical

When abrasive material is transported through steel pipe in mining applications, typically as pumped slurry, the pipe can quickly be eroded from the inside out, which in more extreme cases can result in pipe leaks and even failure, or significant maintenance costs and downtime for pipe replacement.

ceramic composite

Section of the composite pipe

ceramic microstructure

Microstructure of ceramic layer

Mechanical properties of ceramic lined pipe

FeAl2O4 distributes among alumina dentrite. Although the ceramic layer was solidified from one end to another end of a pipe, the microstructure of ceramic layer was almost uniform throughout the whole length of the pipe.

ceramic resistance
Resistance to thermal shock
ceramic used
A composite elbow was used
in a mining plant for about
fifty thousands hours.

Hoop Strength

Hoop strength is the resistance against radial pressure. The strength of the ceramic -lined steel composite pipe is 300 to 500MPa.

Compression-Shear Strength

Compression-shear strength is the bonding strength at the interface between the ceramic layer and the steel pipe. The compression-shear strength of the ceramic-lined composite pipe is 15 to 20MPa.

Resistance to Mechanical Shock

The ceramic layer does not crack or flake off when the composite pipe receives a mechanical shock.

Resistance to Thermal Shock

The ceramic layer does not crack or flake off when heated to 800℃ and then quenched.

Resistance to Abrasion:

The ceramic-lined steel composite pipe has exceptional resistance to abrasion. Its service life in materials transportation with hard abrasives is more than 20 times longer than in common steel pipe.

For these abrasive applications, mild steel pipe is not tough enough to stand up to the abuse for more than a year or two. As a result, maintenance engineers are seeking superior piping alternatives to reduce maintenance and prolong system life, at a price point that will not significantly impact the budget.

The general servicelife of common steel elbow is about 700 hours.

Good Weld Ability

The ceramic-lined steel composite pipe can be joined by welding the steel pipe layer.

Light Weight

The ceramic-lined steel composite pipes are lighter than alloy pipes, cast iron pipes, and cast stone pipes, which reduces the expense of transportation and makes the pipes easier to install.

Convenient Installation

The ceramic-lined steel composite pipes can be easily connected by welding, or with flanges and soft easy connectors.

The composite pipes have good corrosion-resistant. There is no evidence of corrosion filling the composite pipes with bitter for one year (left), but the common steel pipe under the same condition is corroded seriously (right).

Ceramic liner composite pipe is different from traditional seamless steel pipe, wear-resisting alloy cast steel pipe, cast stone pipe, steel plastic pipe and steel rubber pipe.

Main properties of ceramic lined pipe

Content of Alumina≥95%
Density≥3.5 g/cm3
Rockwell Hardness≥80 HRA
Impact Strength≥850 Mpa
Bending Strength ≥290MPa
Breaking Temper≥4.8MPa·m1/2
Coefficient of Linear Thermal Expansion20W/m.K

Characteristics of ceramic lined pipe

Self-propagating high temperature synthesis technology of corundum ceramic composite steel pipe is that is, “SHS” technology composite, is a national High-tech “863” project, is the original national metallurgical Industry Department, the Ministry of Electricity Project focused on the promotion of new products, the tube from within to outside by ceramic (corundum) layer, transition layer and steel layer composed of three parts.

Good wear resistance

Ceramic composite pipe due to corundum ceramic (a-AL2O3), Mohs hardness of 9.0 is equivalent to more than HRC90. Therefore, it has high wear resistance for abrasive media conveyed by industries such as metallurgy, electric power, mining, and coal. It has been confirmed by industrial operation that its wear life is ten times or even several ten times that of hardened steel.

Small operating resistance

SHS ceramic composite pipe is not like a convex spiral line on the inner surface of a seamless steel pipe because the inner surface is smooth and never corrodes. The inner surface roughness and clear water resistance characteristics of the relevant test units were tested. The smoothness of the inner surface was better than that of any metal pipe. The clear drag coefficient was 0.0193, which was slightly lower than the seamless pipe. Therefore, the tube has the characteristics of small running resistance and can reduce operating costs.

Corrosion, anti-scaling

Since the steel ceramic layer is (a-AL2O3), it is a neutral characteristic. Therefore, it is resistant to acid and alkali and seawater corrosion, and it also has anti-scaling properties.

Temperature resistance and heat resistance

Due to the corundum ceramic (a-AL2O3), it is a single stable crystalline structure. Therefore, the composite pipe can operate normally in the long-term temperature range of -50–700°C. Material linear expansion coefficient of 6-8 × 10-6/0C, about 1/2 of the steel pipe. The material has good thermal stability.

The cost of the project is low

Ceramic composite pipes are light weight and affordable. It is 50% lighter than the cast stone tube with the same inner diameter; it is 20-30% lighter than the wear-resistant alloy tube, and it has good wear resistance and corrosion resistance because of its long service life, thus supporting hanger costs, transportation costs, installation fees, and Reduce operating costs. Comparing the project budget of the design institute and construction unit with the actual project, the project cost is equivalent to the cast stone. Compared with the wear-resistant alloy pipe, the project cost is reduced by about 20%.

Easy installation and construction

Because of its light weight and good welding performance. Therefore, welding, flanges, quick coupling, etc. can be adopted, and the construction and installation are convenient, and the installation cost can be reduced.

Other Knowledge

Ceramic steel pipe and traditional steel pipe, wear-resistant alloy cast steel pipe, cast stone pipe, as well as steel plastic, steel rubber pipe, etc. have essential differences. The outer layer of ceramic steel pipe is steel, and the inner is corundum. The Vickers hardness of corundum layer is as high as 100-1500 (Rockwell hardness is 90-98), which is equivalent to tungsten cobalt hard gold. The wear resistance is more than 20 times times higher than carbon steel pipe, it is superior to the corundum grinding wheel which is usually bonded. Now the corundum grinding wheel is still the main grinding wheel of the grinding mill. The corundum layer in the ceramic steel tube can wear away the corundum grinding wheel. The abrasion resistance of ceramic steel tube is mainly by the inner layer of several millimeters thick corundum layer, its Morse hardness is 9, second only to diamond and SIC, in all oxides, its hardness is the highest. The inner liner ceramic wear-resisting steel pipe is made by SHS high temperature synthesis-centrifugal method, the melting point of corundum in ceramic steel pipe is 2045 ℃, the corundum layer and steel layer have special structure and stress field because of the process reason. Under normal temperature, the compressive stress of the ceramic layer, the tensile stress of the steel layer, the two opposites, into a balanced whole. Only when the temperature rises to more than 400 ℃, because the thermal expansion coefficient is different, the new stress field produced by the thermal expansion and the original stress field in the ceramic steel pipe cancel each other, so that both the ceramic layer and the steel layer are in a free equilibrium state. When the temperature rises to 900 ℃ the inner liner ceramic wear-resistant steel pipe into the water, repeatedly soaked repeatedly, the composite layer does not crack or cracking, showing the incomparable thermal shock resistance of ordinary ceramics. This performance is of great use in construction, because the outer layer is steel, in addition to heating the inner layer does not crack, in the construction, the flange, blowing, explosion-proof doors can be welded, but also can be directly welded to connect, which is more than wear-resistant cast stone pipe, wear-resistant cast steel pipe, Rare-earth wear-resistant steel pipe, bimetal composite pipe, steel pipe, Steel rubber pipe In the construction is not easy to weld or welding more than a chip. Internal liner ceramic Wear-resistant steel pipe resistance to mechanical impact is good, in transport, installation beat and the two support between the weight bending deformation, the composite layer does not break off.

At present, the practice of dozens of thermal power plants shows that the wear resistance of the inner-lined ceramic steel tube is high, and the resistance to fluid scouring is strong. In the first air duct, the bending pipe wear the most quickly, the wear resistance of the inner liner ceramic wear-resisting steel pipe is more than 5 times times higher than that of the thick wall wear-resisting cast steel elbow. In practice, the inner liner ceramic wear-resistant steel pipe after 1-2 years to open observation and measurement, the composite layer has no obvious wear or fall off, in the same size and unit length of the pipeline, the internal liner ceramic wear-resistant steel tube weight only wear-resistant cast steel pipe or bimetal composite pipe of about 1/2, the cost of each of the meters reduced 30–40%, Only cast stone pipe and Rare-earth wear-resistant steel pipe weight of about 2/5, per meter project cost reduction of more than 20%. In the corrosive or high-temperature place to use the liner ceramic wear-resistant steel pipe, its price is only a stainless steel tube, nickel-titanium tube of a fraction of. Fluid pipeline transportation is not only used in the power industry, but also in metallurgy, coal, petroleum, chemical, building materials, machinery and other industries. When the pipe is transported with large grinding material (such as ash residue, pulverized coal, mineral fine powder, tailings cement, etc., there is a problem of fast abrasion of pipe, especially the bending pipe wear fast; when conveying a strong corrosive gas, liquid or solid in the pipeline, there is a problem that the pipeline is corroded and destroyed quickly. When conveying the material with high temperature in the pipeline, there are some problems such as the price of heat-resisting steel pipe is very expensive. The internal liner ceramic wear-resistant steel pipe market, these problems are solved.