Abrasion Resistant Ash and Slurry ConveyingPipeline
Recently, excellent abrasion resistance is required for thepipes used in the slurry transporting systems, for example, which transport thecoal ash in pulverized coal firing boilers. We have developed abrasion resistantpipe for transportation of slurries and ash named ceramic lined steel pipeswhich provide significantly longer life .
1. The Manufacturing Process ofCeramic Lined Steel Pipe and Elbow:
SHS(Self-propagating High-temperature Synthetic process)ceramiclined steel pipe and elbow create a new generation of abrasion and corrosionresistant engineering pipeline.The composite steel pipe is composed of threelayers: ceramic, intermediate, and steel layers. The ceramic layer is formed bymolten alumina at a temperature above 2500 degree. The molten alumina producedfrom the reaction Fe2O3+2Al=2Fe+Al2O3 spreads on the inside wall of the steelpipe under the influence of a centrifugal force, then solidifies, so the ceramiclayer has high density and smooth surface and bonds to the steelpipe.
Abrasion Resistant Ceramic Lined Pipes have been uniformlyproduced by a thermite reaction induced under the influence of a centrifugalforce ("Centrifugal Thermite Process") without any high-temperature furnacefacilities. The characteristic feature of the present process for forminguniform ceramic layers is in its reaction propagation as well as the reactionheat and centrifugal force. It is very important in improving the quality of theceramic lined pipes to find the proper conditions of the reactant andcentrifugal force; the former mainly determines the produced ceramic layerquality and the latter the achievement of layer separation and the mechanicalproperties of the pipes. Ceramic lined tube has great resistance againstcorrosion, abrasion and thermal shock.
2. Features andAdvantages:
1). High Abrasion Resistant:
Vickers hardness of the corundum lining is HV1100 to1500, as high asthat of tungsten-cobalt hard alloys, and the abrasion resistance is 20 times ascarbon steel pipes. The composite ceramic lined steel elbow was used in a miningplant for about fifty thousands hours. The general service life of common steelelbow is about 700 hours.
2). Corrosion Resistant:
Corundum is a neutral material, and is and fouling-free.
3). Heat Resistant:
Ceramic lined composite steel pipe can work under circumstances of -50to 800 Celsius degree .
4). Lower Weight and ConvenientInstallation:
The ceramic lined steel pipes are lighter than alloy pipes, cast ironpipes, and cast stone pipes and can be welded or connected through flanges,which reduces the expense of transportation and makes the pipes easier toinstall. For the pipes with the same sizes, types and length, the weight ofceramic pipe is about 1/2 of the wearable cast alloy steel pipe's, while thecost has reduced 10%~20% per meter. The weight of ceramic lined steel pipe isabout 1/3 of the cast stone bent pipe's, 1/2 of the cast stone straightpipe's.
5). Lower Cost :
Ceramic lined pipes can take place of expensive stainless steel,titanium, nickel, cast stone or alloy pipes. Extended service life can alsoreduce maintenance cost.
Remarks:
1. Under the direction of the arrow diagram for theexport direction.
2. Bend radius is usually 1.5-5 times thediameter of steel pipe (1.5-5D).
3. Othe specifications of thecompsite pipe can be manufactured accord to the userrequirments.
4. The weight is caculate by theoretics, maybehave some tolerance, the real weight will be weigh in afer themfinished.
Hoop strength is the resistance against radialpressure. The strength of the ceramic -lined steel composite pipe is 300 to500MPa.
