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FAQ

 Boiler tubes are used in fire-tube boiler, a type of boiler in which hot gases from a fire pass through one or more tubes running through a sealed container of water.






How to get rid of surface stains of cracking tube

How to get rid of surface stains of cracking tube follow the steps below:

The first step is to clean, we must first petroleum cracking tube surface oil, dirt, grease, and some other substances removed. The second step is naturally acid, generally speaking, there are two pickling treatment, a chemical treatment, another treatment method is electrolysis, which can be handled in two ways petroleum cracking tube surface cleaning clean, but chemical pickling is a pipeline anti-corrosion measures.

The third step is necessary to use the tool to the surface of the oil cracking pipe polished, although the effect may not be very good polish, but this procedure is also indispensable. The final step is to make the surface of petroleum cracking tube jet, one can remove some of the dirt, the second is to make the roughness of petroleum cracking tube more evenly.

For petroleum cracking tube defects formed on the surface there are many, but certainly there are a lot of different reasons, the specific form of the crack is different, often found defective for its appearance on petroleum cracking tube we can see, the main reason for its main form by the following points. In fact, for the production process, the emergence of various drying phenomena of its raw materials for steelmaking summer rainy season or when it will produce up to steel gas content's sake.

In the process, the ingot when heated due to heating of the air bubbles are burned through, it will have more cracks after the rolling, which will meet the petroleum cracking tube relatively thin, dense and sizes, its length ranging from cracks, these things collectively referred to as hairline, this is a defect. So the cause of the surface oil cracking tube defects are many, so we have to remedy. After oil cracking pipe handling, appearance becomes smoother, more beautiful. Although after the rust will not affect the use again, but if we do the work in advance, so do not bother it. We buy petroleum cracking tube among the first to note that it is not a strong corrosion resistance, have a longer life does not have to select a high-quality petroleum cracking pipe products that can reduce our future work a lot of trouble.

Small diameter high-pressure boiler tube surface defects that affect the quality, mainly due to waste generation.

Boiler pipes often in high temperature and high pressure work, pipe smoke and water at high temperature steam oxidation and corrosion effects will occur, thus requiring durable steel with high strength, high oxidation resistance, and good organizational stability, high pressure boiler tube in addition to chemical composition and mechanical properties, hydrostatic testing done by the root, to be flaring, flattening test. Steel to heat treatment delivery. In addition, the finished steel microstructure, grain size, there are certain requirements decarburization.

High-pressure boiler tubes are seamless steel pipe categories. Seamless same manufacturing method, but used in the manufacture of steel pipe, there are strict requirements. Often in high-pressure boiler tubes at high temperature and pressure conditions of use, the tube under the effect of high temperature gas and water vapor, oxidation and corrosion will occur. Require durable steel with high strength, high resistance to oxidation corrosion, and have good organizational stability.

High-pressure boiler tube is mainly used to manufacture high-pressure and high pressure boiler superheater tubes, reheater tubes, windpipe, the main steam pipe. High-pressure boiler tubes for low and medium pressure boiler (working pressure is generally not more than 5.88Mpa, working temperature below 450 ℃) of heating surface tubes; used for high-pressure boilers (above 9.8Mpa working pressure in general, the working temperature of 450 ℃ ~ 650 ℃ between) the heating surface tubes, economizer, superheater, reheater, petrochemical industrial pipe.

Hardness testing methods of high-pressure boiler tubes

High pressure boiler tube hardness testing should take into account its mechanical properties, which is related to stainless steel as raw material for the deformation, such as punching, cutting processing performance and quality.

Therefore, all of the high-pressure boiler tubes need to conduct mechanical tests. Mechanical performance testing method is mainly divided into two kinds, one kind is tensile test, the other kind is usually hardness test.

Tensile test is the high pressure boiler tube sample, high pressure boiler tube tend to sample to the fracture on tensile testing machine, mechanical properties and determination of one or more, usually only determination of tensile strength, yield strength, break elongation, and reduction of area. Tensile test is the most basic mechanical properties of metallic materials testing methods, almost all of the metal material, as long as the requirements of the mechanical properties of the high pressure boiler tube, the provisions of the tensile test. Especially those appearance and high pressure boiler tube is not good for the material of hardness test, tensile test became the only means of mechanical properties testing.

Steam boilers

A steam boiler is a device used to create steam by applying heat energy to water.

High Frequency Resistance Welding

A continuous helical fin is attached to the base tube by high frequency electric resistance welding in order to give an efficient and thermally reliable bond. Fins can be either solid or serrated (segmented). The weld produced in this process is a true forge, blacksmith weld. This type of weld is comprised of a fusion between two portions of parent metal without the introduction of a filler material. The weld is simply produced by heating the interfaces to be joined to a plastic state and applying pressure.

Used in boilers, furnaces and fired heaters for efficient heat recovery.

High-pressure boiler tubes are frequently occurs fault because of high temperatures, affecting the entire heating system, mainly due to an internal boiler for heat treatment is not perfect, a lot of heat can not be effectively converted and timely treatment.

High pressure boiler tube hardness testing should take into account its mechanical properties, which is related to stainless steel as raw material for the deformation, such as punching, cutting processing performance and quality.

Therefore, all of the high-pressure boiler tubes need to conduct mechanical tests. Mechanical performance testing method is mainly divided into two kinds, one kind is tensile test, the other kind is usually hardness test.

Finned tubes are used in applications involving the transfer of heat from a hot fluid to a colder fluid through a tube wall.

The rate at which such heat transfer can occur depends on three factors:

  • the temperature difference between the two fluids;
  • the heat transfer coefficient between each of the fluids and the tube wall;
  • and the surface area to which each fluid is exposed.

Boiler pipe forming include fin tube, serpentine tube and reaming welding.

Boiler tubes need take for a variety of molding in the boiler manufacture and installation process

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