Bimetal Clad Elbow

The Bimetal clad elbow made of high chromium cast iron pipe is an alloy steel for high temperature and high pressure service.

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Bimetal Clad Elbow

Bimetal clad elbows are used to to allow one pipe to join another pipe at some degree or angle.

Special Corundum ceramics made of rare metal oxides as solvents and sintered at high temperature by 1730 ℃ through bonding, welding, mosaic, riveting and socket technology, a variety of wear-resistant ceramic pieces, block brick materials in the pipe wear surface, so as to form a surface with excellent wear resistance, and the matrix is still using the composite pipe of ordinary metal.

Layer construction

45° Elbow High Chromium Alloy

Do you know what’s the cladding steel pipe used for?

It not only satisfies the special requirements, but also saves costs.

In a clad line pipe, the corrosion-resistant alloy forms a complete barrier layer on the internal surface of carbon or low-alloy steel pipe (usually referred to as the “backing steel”). In general, use of clad or bi-metal-lined pipe allows the economic use of expensive CRA materials,It has been widely concerned and used in many other fields abroad.

Features of High chromium cast iron pipes

The wear resistance of the high-chromium bimetallic lined pipe is at least many times that of ordinary steel pipes. The bimetallic composite steel pipe has inner and outer double layers of metal, the inner lining is made of wear-resistant cast iron, the inner lining material has good wear resistance and corrosion resistance, and the outer layer material has high mechanical strength and high impact resistance. The lost foam composite process is directly adopted, and the metallurgical composite is formed by casting, which is safe and reliable to use.

Lined high-chromium bimetallic composite pipes include high-chromium bimetallic composite straight pipes lined, high-chromium bimetallic composite elbows lined, high-chromium bimetallic composite tee lined, Lined with high-chromium bimetal composite multi-pass, lined with high-chromium bi-metal composite reducer, lined with high-chromium bi-metal composite flash buffer device, etc.

Chrome-Moly

  • Chromium-Molybdenum Alloy Steel or Chrome-Moly, CrMo is an alloy steel intended for high temperature and high pressure services.
  • Chrome-Moly is used in the power generation industry and the petro-chemical industry because of its tensile strength, corrosion resistance and high-temperature strength.
  • Chrome-Moly has a better strength to Weight ratio than steel, which enables designers to use thinner wall pipe or smaller diameter tubing to reduce overall weight.
  • Chromium-Molybdenum Alloy Steel has strong resistance to rupturing at high temperatures and high pressures.
  • Chrome-Moly is also resistant to cracking from hydrogen attack and hot sulfide corrosion cracking.
  • Chrome-Moly grades P-11, P-22, P-91 and P-92 are used in the power industry.
  • Chrome-Moly grades P-5 and P-9 are used in petro-chemical refinery processes.
  • Chrome-Moly Forged Fittings & Flanges are available in grades F-5, F-9, F-11, F-22, F-91, F92.
  • Chrome-Moly Alloy Butt Weld Fittings are available in grades WP-5, WP-9, WP-11, WP-22, SP-91, WP-92.
  • F11 and F22 meet NACE-MRO 175.

Bimetal wear resistant products including: double metal wear-resisting straight pipe and double metal wear-resisting bend, double metal wear tee, double metal wear resistance reducer adopts the pipe fittings such as vacuum suction casting composite process, its advanced technology, effectively solve the problem of the bent pipe cannot be composite, bending and other various special-shaped pipe can do the whole compound, don’t change the material flow in the pipe bending trajectory, reduce resistance material conveying.

The outer wall of the centrifugal pipe is made of carbon steel, which ensures that the bimetal wear-resistant pipe has high mechanical strength and impact resistance.The inner lining wear resistance layer adopts the anti-wear alloy steel series independently developed by our company. The steel mainly adds alloy such as cr-ni-mo-cu-re and so on. Through the tempering heat treatment process, the alloy steel has strong wear resistance and corrosion resistance, high mechanical strength and impact resistance.

The whole set of process of our factory is the first in China, which fills the blank of anti-corrosion and wear-resistant industrial pipeline in China and has reached the international advanced level. It has been widely used in mining, metallurgy, coal, electric power and other industries, and is an ideal wear-resistant pipeline.

Physical Properties of Bi-metal clad pipe

Flexure Strength
MN/㎡
Tensile Strength
MN/㎡
Elongation
%
Cross Section Stretch Ratio
%
Impact Toughness
J/c㎡
Hardness of Wearable Layer
HRC
Hydrostatic Testing Pressure
Mpa
>610 >700 5 5.1 >15 >38 5.6-12.9

What is Bimetal clad pipe?

Bimetal wear resistant pipe adopts centrifugal casting technology in the production process of straight pipe.

Bi metal clad pipe layer structure

This technology is to fuse and shape both metals in liquid state, realizing the purpose of real metallurgical bonding. The shear strength of the binding layer is higher than that of the metal itself, and completely realizes the mechanical complementarity between base layer and wear resistant layer.

Bimetal wear resistant pipe, including: double metal wear-resisting straight pipe and double metal wear-resisting bend, double metal wear tee, double metal wear resistance reducer adopts the pipe fittings such as vacuum suction casting composite process, its advanced technology, effectively solve the problem of the bent pipe cannot be composite, bending and other various special-shaped pipe can do the whole compound, don't change the material flow in the pipe bending trajectory, reduce resistance material conveying.

The outer wall of the centrifugal pipe is made of carbon steel, which ensures that the bimetal wear-resistant pipe has high mechanical strength and impact resistance.The inner lining wear resistance layer adopts the anti-wear alloy steel series independently developed by our company. The steel mainly adds alloy such as cr-ni-mo-cu-re and so on. Through the tempering heat treatment process, the alloy steel has strong wear resistance and corrosion resistance, high mechanical strength and impact resistance.

The whole set of process of our company is the first in China, which fills the blank of anti-corrosion and wear-resistant industrial pipeline in China and has reached the international advanced level. It has been widely used in mining, metallurgy, coal, electric power and other industries, and is an ideal wear-resistant pipeline.

What is a clad pipe made of?

The base material is carbon steel or low alloy steel. Clad pipes comply with the most stringent requirements of strength and corrosion resistance. The carbon steel outer pipe (backing steel or base metal) complies with the static requirements of strength and durability whereas the high alloyed inside pipe provides protection against corrosion.

What is a bimetal?

A bimetal or thermostatic metal is a sheet or strip of two or more composite materials having different coefficients of linear thermal expansion bonded by riveting, brazing or welding.


Bi metal clad pipe applicable areas

Because oil and natural gas contains a large amount of corrosive media such as hydrogen sulfide, carbon dioxide and chloride ions, especially the content of corrosive components in the oil and gas medium before pipeline purification in the seabed oil and gas field is high, and some even require heat transfer, and internal corrosion problems are very prominent.

Bi metal clad pipe applicable areas

The use of stainless steel or corrosion-resistant alloys in large quantities is not economical. Double metal clad pipes are a good choice.

The bimetal clad pipe structure uses a corrosion-resistant alloy tube (stainless steel or corrosion-resistant alloy) as the inner liner (wall thickness 0.5-3mm) to contact the corrosive medium and carbon steel or low-alloy steel as the outer base pipe to withstand the pressure. low. Generally, the double-metal clad pipe contains 316L austenite stainless steel as the inner liner in the case of containing CO2 medium, and 2205 and 2505 duplex stainless steel can be used as the medium containing CO2 + small amount of chloride, when H2S+CO2 is contained. + Chloride, the inner liner should be 028, G3, INCONEL625 and Inconel825 nickel-base or iron-nickel alloy, in order to ensure the corrosion resistance of the pipeline, but also can choose the titanium alloy and other materials with excellent corrosion resistance as lining. The outer layer material is usually API 5L X42, X50, X60, X70, ASTM-A106GB and A335-P22 and other materials, so as to ensure the strength of the pipeline.

Casing pipe for oil and gas transportation

Choosing stainless steel such as Incoloy625 and Incoloy825 for inner tubes to ensure the corrosion resistance of the pipe. The outer pipe are usually X42, X50, X60, X70, A335-P22 and other materials to ensure the strength of the pipeline. The American Petroleum Association (API) has developed the standard for composite pipes for pipelines,with the serial number API 5LD:Cr-Mo steel,super 13Cr, G3, C028 and other oil well tubes and the nickel-base alloy cladding tubes such as 825, 028.

Boiler

The steel tube for superheater should have high temperature strength under the condition of 650 and 35 MPa steam,excellent surface temperature and corrosion resistance, and inner surface resistance to water vapor oxidation.

Japan Sumitomo metal company choose SUS310S, 35Cr-55Ni, 40Cr-55Ni as outer base tube and 17-14CuMo,Alloy800Has the inner tube,developed super supercritical boiler superheater cladding pipe.

Sandvik,a Sweden Steel Corp successfully developed carbon steel as an inner pipe and Sanicro28 steel with good corrosion resistance as outer pipe. The cladding steel pipe made by Sandvik does not need any change in the boiler structure design and can be used directly.

Waste incinerator

Cladding steel tube for waste incinerator.The outer tube can be made of Sanicro65 alloy, and the inner pipe may be carbon steel or chromium molybdenum steel with resistance to stress corrosion cracking.Europe and the United States have used 2 million meter composite steel pipe since the first installation cladding pipe incinerator superheater and water wall tubes in the 1971.

Heat exchanger

Cladding steel pipe used for heat exchanger should also have good thermal conductivity and a certain strength and corrosion resistance.

Sandvik manufactured cladding pipe with high alloy nickel chromium alloy 800 as the inner tube and the low-alloy steel ASTM A213 Ti2 as the outer pipe.NKK company from Japan made cladding pipe with API 5L-16MnV steel as its outer pipe and NIC42 steel as inner pipe.

Used for wear-resistant steel

A Japan company have made cladding steel pipe with SUS316L corrosion resistant steel for outer pipe,Stellite No12 alloy for inner pipe,after 4 years is still new.They has also been well applied in the pneumatic conveying pipe of other micro powder particles, and the demand is increasing.

Marine environment

Inner pipe:Nickel, Titanium stainless steel or Copper alloy.

Outer pipe:Carbon steel or low alloy corrosion resistant steel.

Cladding pipe used for marine environment made by Japan's Kawasaki is widely used as marine heat exchanger tube and seawater desalination of seawater intake pipe. 

Civil areas

Cold, hot water pipes, direct drinking water pipes, heating, solar energy, ground source heat pump; civil construction water supply pipes, water distribution trunk; air conditioning circulation pipe, fine decoration high-grade commercial housing water pipes.

Industry

Oil and gas pipeline, oil and gas wells casing, sewage return pipe; chemical heat exchanger tube bundle; power desalination water, desulfurization pipeline and other metallurgy, desalination, medicine and chemical industry, sewage treatment, new energy, food processing and other industries.


Advantages

  1. The hardness of a good wear resistance superhard wear alloy is greater than 56 (HRC), which has good wear resistance and thermal stability.
  2. Excellent impact resistance, metal binding and thermal shock resistance KMTBCr28 bimetal composite wear-resistant elbow. The joint surface of the two metals is completely metallurgical, safe and reliable. The coefficient of thermal expansion is equal to that of expansion, shrinkage and crack. The outer wall of the elbow is made of steel tube and the inner lining is made of super-hard wear-resistant alloy.
  3. Good resistance to heat and corrosion. The matrix of super hard alloy material has strong resistance to heat and corrosion. Under the action of wet state, corrosion medium and particle scour, it is more suitable to use the super hard wear-resistant alloy. Under the condition of dry state in which abrasive wear is the main failure mode, a kind of super hardness wear-resistant alloy material which can be obtained by heat treatment is selected.
  4. The bimetal wear-resistant pipe with low composite cost and good quality is manufactured by the internationally advanced epc casting process with high yield, good compactness, uniform thickness and stable quality.
  5. The bimetal wear-resistant pipe can be connected by flange, quick joint and direct welding.In addition, due to the high resistance and beating performance of the composite pipe, when partial blockage occurs in the pipe system maintenance, it can be knocked or hammered at will, and can be cut, unloaded, welded and installed at will.

Technology

High chromium cast iron is the third generation of white cast iron developed from ordinary white cast iron and hard nickel cast iron.

Bi metal clad pipe applicable areas

Process requirement

  1. Wear-resistant elbow is made of bimetal wear-resistant composite.
  2. The general manufacturing method is made by the combination of the vacuum absorption casting process of the vanishing mould, and the manufacturing process of the commodity shall be indicated in other processes.
  3. Adopt composite alloy steel wear-resistant layer, each elbow shall be eccentric compound, and the outside of the elbow shall be thickened according to the working condition to achieve the life design of the outside and inside. In order to reduce the resistance of coal powder transportation, the elbow should be smooth and excessive, and the shrimp waist welding method should not be adopted, so as to ensure that the inner diameter of the throughflow at all parts is 510mm, and no convex platform can be found.
  4. Wear-resistant lining is made of high chromium alloy (not lower than KMTBCr28), with service life over 2 years and annual wear less than 5mm.The outer wear resistant lining thickness is 28mm, the inner wear resistant lining thickness is 22mm, and the hardness of HRC is greater than 55. Outer pipe of lining part 558*10, connecting pipe 508*10, outer ring 558*22, material is 10 steel. Seamless pipes (or welded pipes) can be used, and their performance should meet the requirements of GB2087, GB8163.

The bimetal wear-resistant tube inner wall KMTBCr28 has stable quality and good comprehensive performance. Adding a certain amount of rare earth elements can improve the alloy quality of steel, refine the grain and form a protective film on the surface.A certain amount of Mo was added to make the alloy have certain antioxidant effect and increase service life at high temperature.A certain amount of boron carbide can be added to control the hardness in the range of HRC45 ~ 65, and solve the contradiction between the hardness and weldability of wear-resistant steel.

Quality requirements

The inner and outer surface of bimetal wear-resistant elbow should be smooth and clean, without burrs, burrs, cracks, loose, pores or bubbles;The inner wall of the wear-resisting elbow should be smooth without accumulated powder.The bend should have good thermal shock resistance. When there is a sharp change in temperature or welding connection, the inner layer of the wear-resistant pipe will not break and spalling due to the expansion or contraction of the inner layer.The dimensional deviation shall meet the requirements of product drawings and order, agreement, and shall meet the provisions of GB3092, GB8162 and GB8163 without special requirements.The thickness deviation of lining is + / – 1.2mm.


Features of centrifugal casting for bimetal wear resistant pipe production process

(1) Centrifugal casting technology enables the molten steel to solidify and form under the gravity condition, which is dozens of times higher than conventional casting. It solves the problem of loose inside the casting tube billet, has high metal density, and has good discharge and exhaust effect.

(2)The size accuracy of centrifugal cast pipe is high and the wall thickness is even, which provides a favorable guarantee for the size accuracy of subsequent processed products.

(3)Centrifugal casting process has high flexibility for the production of steel pipes of small batch, multiple varieties and specifications, high quality and high value-added steel.

What is CRA Cladding?

CRA basically means corrosion resistant alloy.
It’s a material that is built for cladding because its main purpose is to enhance a pipe’s resistance to corrosion.

What is Elbow Cladding?

Pipe elbow cladding is the process of applying a cladding material to elbow pipes.
It’s done on a more careful manner than the usual.
This is because elbow pipes can change throughout the entirety of the process.

Where Can Pipe Cladding be Applied to?

Particularly, the process of pipe cladding benefits the oil and gas industry the most.

However, it can also be used by other industries such as:

What is Pipe Lining?

Pipe lining is the process of prolonging the lifespan of pipes.

It can also be used, however, to restore a pipe from natural damages such as:

Lined Pipes vs. Clad Pipes

Pipe lining and pipe cladding are processes that are far from each other.

Lining is the process of mechanically bonding materials to pipes for restoration. Some of the uses of pipe lining include:

Cladding is the procedure of metallurgical bonding of clad materials to pipes. Some of the major uses of pipe cladding include:

Who Can Help You With Pipe Cladding?

There are a lot of companies that utilize state-of-the-art pipe cladding equipment.

We have cutting-edge technology that can complete projects ahead of time.

Some of the most notable features that our pipe cladding equipment have include:

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