Durable and corrosion resistant Sintered mesh screens for your application

Made from durable and corrosion resistant materials, sintered wire mesh screens are used to form a uniform high porosity filter medium. It demonstrates a considerably low pressure drop, high permeability and outstanding dirt holding capacity.

Additionally, sintered metal mesh can be pleated to increase the functional filtration area of a screen, hence further increasing dirt holding capacity, decreasing maintenance and maximizing on-stream processing. With the feasibility to develop fibre screens to meet specific application requirements, combined with inherent durability, sintered mesh screens can be cleaned in situ without interrupting process flow, hence offering the ultimate in process economics by decreasing downtime to a minimum.

Materials used to fabricate sintered wire mesh screens are stainless steel 316L grade, Inconel, Hastelloy and Monel, depending on the requirements of the service conditions. These materials provide excellent resistance to various chemicals and can withstand high temperatures up to 1000oC. These sintered mesh screens ensure greater media uniformity without welds, providing increased corrosion resistance.

High performance sintered mesh screens also offer good permeability, high tensile strength and are available from single wrap designs to multiple layer structures to optimize the available area. These screens can be manufactured in diffusion bonded versions to increase performance security of pore shape and size and have the widest range of pore sizes of any type of filter media.

The precision sintered mesh screens can be made from different types of weaves such as Plain square weave, Reverse plain dutch weave and more. Dutch twill weave is used for the widest selection of surface filtration performances.

The diffusion bonded stainless steel mesh is built by using advanced sintering processing. It is used to construct screens for both high flow and low flow rates to meet your application requirements. These screens can be easily customized to meet the specific demands of materials, strengths, flow requirements, thickness, micron rating and environment. For particular atmospheric conditions, they can be used in temperatures up to 540oC with intermittent service peaks up to 650oC or 1202oF.

Usually made from 316 stainless steel, these screens are also made with Inconel, Hastelloy and Monel grades for service in the most aggressive conditions.

Features and benefits of sintered mesh screens

·         Excellent and mechanically strong structure

·         Made in different shapes without expensive support structures or strips

·         Can be reused as structure allows regular cleaning, offering an economical choice

·         Resistance to various chemicals

·         Made in different types of weaves

·         Precise size

·         Good permeability

·         Robust construction

·         Made in single layered design to complex multi-layered structures to optimize the functional area

·         Smooth surface for backwash applications

·         Broadcast range of pore sizes of any filter media type

·         Ability to withstand diverse process conditions

Applications

·         Catalyst recovery and retention

·         Polymer melt

·         Chemical production

·         Liquids and liquid backwash

·         Pharmaceutical powder recovery

·         Agrochemical

·         Vent filters

·         Gasification and chemical production

Heanjia is a well known manufacturer of sintered mesh screens that are used in various applications in the challenging service conditions. Contact us to know more.

Multilayer sintered mesh screens for vigorous chemical filtration

Sintered wire mesh screens are suitable for filter cartridges that need robust mesh resistant to vigorous chemicals. These screens are available in wide range of sizes to suit industry filter structures and also are made in specific sizes. The robust screens are made from stainless steel and special alloys.

Multilayer sintered mesh

Sintered screen multilayer mesh uses several layers of mesh to make a screen that offers high filtration efficiency with strength. Standard mesh structure comprises an external security layer, an internal main filter layer, drainage layer and eventually two strengthening layers to provide strength. All mesh layers are sintered to develop a single sheet of filter screen.

The sintered mesh screens can be fabricated in cylindrical or sheet formats and in a wide variety of lengths and diameters.

Cleaning

Reverse flow: It is used when most of the contaminants are larger in size as compare to pore size of the screen, reverse flowing the liquid or gas through the element will often be sufficient for cleaning. Generally a flow of minimum 2 times the forward flow offers adequate cleaning.

Ultrasonic cleaning: Surface contaminants can be eliminated by ultrasonic cleaning in a bath comprising detergent, deeply plunged particulate cannot be removed.

Chemical cleaning: Different types of chemicals such as acids, caustics, solvents are used to dissolve the contaminants or service fluids when they are hardened due to contact with air.

Sintered multilayer mesh screens are designed for high temperature applications of industries. The screens can be used for high temperature services up to 480oc. The standard combination of five layerssintered mesh made from stainless steel that is combined through sinter, compression and rolling and made into a type of porous material.

Applications of multilayer sintered mesh screen

Polymer filtration, cross flow filtration, gas filtration, analytical devices, medical equipments, aerosol applications, hot gas filtration, fuel and hydraulic oil filtration, RO pre filtration.

Heanjia offers a filtration solution with long experience in working with designers and end users to supply filtration products to industries like food, beverage, pharmaceuticals and chemical processing. We have developed a range of sintered mesh screens and elements designed to work in the most challenging conditions. We are able to offer a wide range of media that meet the demanding duties.

We can manufacture filter elements in a uniform high porosity filter medium. These elements offer long life and nominal maintenance cost. They provide high strength, good permeability filter medium with a tightly controlled pore size. The robust filter material made from sintered mesh is ideal to use for different types of filtration applications. These screens have a high surface area to provide good flow efficiency and dirt holding capacity.

Materials for sintered wire mesh include stainless steel, Hastelloy, Inconel and Monel. We also provide industrial standard format that easily fits many existing filter housings to perform at higher temperatures.

Which materials should be used with alkalies

Alkaline solutions comprise hydrogen ion in nominal concentrations. Usually corrosion by alkalies results into pitting and other types of localized attack as they develop cathodic layers and corrosion is concentrated at sensitive anodic areas. Austenitic stainless steels and other low nickel alloys may experience stress corrosion cracking or general corrosion in hot concentrated caustic.

Corrosion resistance in alkalies generally enhances with increase in nickel concentration. Nickel 200 and other high nickel alloys provide satisfactory performance in these materials. The most commonly used Inconel bars in alkalies are made from Inconel 625 and 600.

Nickel 200

The excellent corrosion resistance of Nickel 200 is its resistance to caustic soda and other alkalies. Nickel 200 is not corroded by anhydrous ammonia or ammonium hydroxide in concentrations 1%. Higher concentrations can cause quick corrosion in the presence of dissolved oxygen.

Nickel 200 provides outstanding resistance to concentrations of caustic soda at temperatures about as well as melting level. For concentrations below 50% the corrosion rates are nominal being often below 0.1 mpy even in the boiling solutions. With increase in concentrations and temperature, corrosion rates nominally increase.

The major factor influencing the performance of nickel in highly concentrated NaOH is the type of layer developed when kept in its contact. In various conditions, a security layer of black nickel layer is developed that causes remarkable reduction in corrosion rates over prolong exposure. The presence of chlorates in caustic soda solutions increases the corrosion rates of Nickel 200 significantly.  

It has been observed that the influence of oxidizable sulfur compounds results into increased vigorousness of caustic solutions. This effect can be prevented by the addition of adequate sodium peroxide in the caustic solution to oxidize it to sulphates.

Monel 400

Containing high nickel concentration, Monel 400 offers similar resistance as of Nickel 200 to caustic soda in the most of concentrations, however susceptible to stress corrosion cracking in strong alkalies at high temperatures. The corrosion rates of Monel 400 are higher in highly concentrated caustic soda and caustic potash at high temperatures. Monel 400 resists anhydrous ammonia and to ammonium hydroxide solutions to 3% concentrations in the absence of dissolved oxygen.

Incoloy 800 and Incoloy 825

While these alloys provide outstanding resistance to alkaline solutions, the corrosion rate of 0.5 mpy in boiling 50% sodium hydroxide, they are not as resistant as Nickel 200 and are nominally used in alkaline solutions if the corrosive materials are not involved. These alloys may also suffer from stress corrosion cracking in the hot concentrated alkalies.

Inconel 600

Inconel 600 should be stress relieved before use and subjecting to stresses should be minimum. Inconel 600 prevents corrosion in sodium hydroxide at boiling points in concentrations about 80%.

Similar to Nickel 200, exposure to chlorates present in caustic soda corrodes the alloy. With the presence of chromium concentration, Inconel 600 is fully resistant to ammonia solutions for a complete range of concentrations and temperatures.

Inconel 625, C276

These alloys offer advantageous performance in halide based conditions.

Advantages Of Window Screen Mesh Using Aluminum And Copper

Window screens can be made from different kinds of materials but the variety of meshes that are manufactured using aluminum and copper. You can take a look at the advantages of aluminum mesh that is used for alleviating the insects. If you are planning to refurbish or replace the windows at the office or home, here are a few reasons to use aluminum window screen mesh for more protection.

•    While you can get fresh airflow through the windows, it can help you ward off the insects easily.

•    In all those places where the climate is very hot, using aluminum windows can make the screen dense thus preventing the entry of sunlight and heat. It can help you to lessen the cost of cooling in offices and homes and also prevent damage to the carpets, floors and other furnishing materials.

•    You can get protection from leaves, debris, insects, and animals with the installation of the Window screen mesh made from aluminum.

•    The durability of aluminum makes the screen mesh more durable and prevents dents and makes it less susceptible to wear and tear.

•    If you are keen to make some areas darker, using the metal screen mesh made from aluminum and copper provides the right solutions. Due to its durability and strength, it can prevent rust and does not sag.

•    With the application of a protective finish, you can the metal mesh can prevent corrosion and the weaves are stronger than the meshes that are made from plastic.

•    Metal meshes comprising copper not only shows superior strength and durability but when it oxidizes, the screen stays protected from corrosion.

Insect screen mesh

It is true that insect screens come in a variety of material options but aluminum and make a difference when you want to achieve the desired quality and the functions. Whether it is to add to the style quotient or to make the home free from those insects and animals, using a screen mesh is the best option. For those people living in the coastal areas who are especially susceptible to insect bites, the screen mesh made from aluminum not only provides protection but retains its durability over the years.

Grades of screens

You can acquire screens in different grades depending on the use. While the heavy-duty grade is perfect for those places n which greater protection is required from insects and animals, the fine grade variety is ideal insect infestation in the coastal areas. With the use of aluminum, you can prevent the chances of scratching and breaking easily. When it comes to acquiring materials for screen mesh that can sustain strong and gushing wind followed by harsh weather, there is no alternative to the metal variant.

Benefits of aluminum mesh

• Although the color options are restricted in aluminum screen mesh, it is sturdy and durable when compared with the rest of the variants.

• With a long lifespan, it provides resistance and coverage against different kinds of weather conditions.

•   It is resistant to abrasion, corrosion, and rust.

• Aluminum screen mesh can serve you for years when maintained properly, and is lightweight.

Alloys that can be used in Hydrochloric acid solutions

Hydrochloric acid is a reducing acid in its whole concentrations. It has strong acidic character and the vigorous effect of the chloride ion combines to make it an extremely severe. The super alloys containing high nickel are the only materials that provide significant resistance to hydrochloric acid solutions.

In the presence of oxidizing contaminants, the vigorousness of the hydrochloric acid can change drastically hence this fact should be considered while choosing a service material. Alloys recommended for use in hydrochloric acid are Hastelloy bars C276, Inconel 600, Inconel 625, and Incoloy 825.

Function of Nickel 200 and Monel 400

These alloys show similar performance in hydrochloric acid. With acid concentration up to 10%, both alloys show similar performance with corrosion rates in air-free solutions below 10 mpy. When the concentration is increased such as above 15%, the corrosion of Monel 400 increases steeply hence its applications are limited to room temperature for concentrations below 10% in aerated solutions and within 20% in air-free solutions.

The applications of Nickel 200 are feasible in acid concentrations to 30%, in aerated or non-aerated at room temperature. The function of nickel in concentrated hydrochloric acid may be influenced by relatively low solubility of its corrosion products, care should be taken at high paces.

Uses of Monel 400 and Nickel 200 in air-saturated hydrochloric acid above room temperature are limited to concentrations below 3 – 4%. Monel 400 provides significant performance in dealing with 2% concentration at 120oF and of 1% at 180oF

Increased temperature more severely affects Nickel 200 than Monel 400 in 5% acid. These alloys specifically Monel 400 is commonly used in acids at lower temperatures at higher temperatures. In many process formation of hydrochloric acid occurs as a result of hydrolysis of chlorides or chlorinate solvents, acid concentrations are below 0.5%. Nickel 200 and Monel 400 can serve in these concentrations adequately up to 300 to 400oF.

Inconel 600

However Inconel 600 provides significant resistance to dilute hydrochloric acid solutions, its service is adequate unlike to Monel 400. Inconel 600 shows suitable resistance to cold aerated below 2% concentration and good performance at room temperature to concentrations to 20%.

Incoloy 825

Incoloy 825 provides supreme resistance to HCl solutions. Its resistance is widely enhanced by adding copper and molybdenum as well as higher nickel concentration in Incoloy 825.

Inconel C276 offers outstanding resistance to hydrochloric acid because of its high molybdenum concentration and nominal addition of tungsten. Incoloy C276 provide suitable resistance to corrosion in hydrochloric acid solutions up to 3% at boiling point. 

Inconel alloys with presence of molybdenum, offer supreme resistance to hydrochloric acid, specifically in strong concentrations or oxidizing conditions. These alloys offer better performance than Nickel 200 as well as Monel 400. Inconel 625 provides supreme resistance to hydrochloric acid by 9% molybdenum concentration.

Hence high nickel alloys provide significant performance in powerful acids based applications.

How does Stress corrosion cracking occur and how to control it

Stress corrosion cracking involves a conjoint corrosion and straining of a metal resulted by a residual or applied stresses.

Irrespective of the increased use of polymers in the modern times, metals are still an essential part of structures for their high strength, toughness and potential to withstand high temperatures and high pressures. But the metals are prone to corrosion. Corrosion may occur in various forms. Here we discuss the stress corrosion cracking, also referred as SCC.

SCC may include different mechanisms when cracking is commonly caused by hydrogen embrittlement, it is also considered to be a part of SCC.

Stress corrosion cracking is a vigorous type of corrosion, it causes a remarkable loss of mechanical strength  with nominal metal loss, the damage is not evident from the causal evaluation. SCC may cause catastrophic damage to application components and structures. It is found that various major damages involved stress corrosion cracking including high pressure gas transmission pipes, boiler explosion and damage of power units and oil refineries.

The occurrence of stress corrosion cracking depends on the simultaneous presence of three factors:

a sensitive material, condition that cause stress corrosion cracking of that material and adequate tensile stress to cause stress corrosion cracking.

Occurrence of stress corrosion cracking

SCC is not an inevitable process and for various metals in most conditions, it does not occur. Hence it is easy to identify specific combinations of metal and environment that are sensitive to problem. But with the passage of time, more and more combinations are identified, particularly engineers endeavour to use materials more efficiently by increasing working stress and using economical materials.

Austenitic stainless steels experience stress corrosion cracking in hot solutions comprising of chlorides. A high chloride concentration although nominal magnitudes of chlorides are adequate at hot surfaces where chloride concentration may occur or where chloride is concentrated by pitting or crevice corrosion and issues can be noticed in fresh water.

The temperature suitable for SCC is normally above 70oC however stress corrosion cracking may occur at lower temperatures in some conditions, usually more acid solutions. The cracking progresses at low stresses and occurs at a result of residual stresses from welding or fabrication. The cracking is usually transgranular, however it may turn to an intergranular path due to sensitization of steel.

Protection from stress corrosion cracking

The first step to defence in controlling stress corrosion cracking is be informed of the feasibility in the design and development stages. By choosing a material that is not sensitive to stress corrosion cracking in the service condition and by processing and fabricating it suitably, the resultant scc problems can be prevented.

Mechanical needs like high yield strength can be tough to resolve with scc resistance. Residual stress can be eased by stress-relief annealing and is commonly used for carbons steels. Additionally by using high corrosion resistant nickel based alloys such as Hastelloy C276- a SCC resistant alloy, it is possible to significantly the control the problems that occur due to Stress corrosion cracking in various industrial processes.

Monel wire mesh- Excellent performance in Marine engineering

Monel wire mesh is an alloy of nickel (67%) and copper (23%) that has resistance to sea water and steam at high temperatures. Monel wire mesh is strong against de-aerated acids such as H2SO4 and HCL however it is affected by nitric acid & ammonia solutions due to high percentage of copper content.

There are various features of Monel wire meshthat makes it highly useful such as

·        Excellent weldability

·        High resistance to stress corrosion.

·        Low strength in annealed condition, usage of foreign elements and heat treatment helps to increase the strength.

·        Excellent mechanical properties at subzero temperature.

·        High yield & tensile strength.

There are numerous applications in which Monel wire mesh is found such as

·        Crude petroleum stills

·        Industrial heat exchangers

·        Marine engineering

·        Boiler feed water heaters and other heat exchangers

·        Chemical and hydrocarbon processing equipment

·        Valves, pumps, shafts, fittings, and fasteners

·        Crude oil distillation towers

·        Gasoline and freshwater tanks

·        Chlorinated solvents

·        De-aerating heaters

·        Process vessels & pipings

·        Electrical & electronic components

Monel alloy is widely used in marine engineering due to its resistance to corrosion. The corrosion rate of this alloy decreases sharply with increase in the nickel content. The corrosion of Monel 400 in naturally aerated and deaerated Arabian Gulf water (AGW) and 3.5 % NaCl solutions was studied. The work has been carried out using cyclic potentiodynamic polarization, chronoamperometric current-time, open-circuit potential, and electochemical impedance spectroscopy measurements along with scanning electron microscope (SEM) and energy dispersive X-Ray analyzer (EDX) investigations. Polarization data showed that AGW is more corrosive than 3.5% NaCl towards Monel and the deaeration process decreased the corrosion of Monel in both media. Chronoamperometric curves confirmed the results obtained by polarization measurements that the uniform and pitting corrosion of Monel 400 were reduced in the deaerated AGW and 3.5% NaCl solutions. Impedance spectra showed that the surface and polarization resistances recorded higher values in deaerated solutions. SEM/EDX investigations indicated that the corrosion of Monel 400 proceeds by the selective electrodissolution of nickel that allows copper enrichment on the surface of the alloy.

Monel 400 alloy is used in the desalination technology industry and other marine engineering fields due to its durability in natural seawater. 

Monel 400 alloy contains 60-70 percent nickel, 20-29 percent copper and small amounts of iron, manganese, silicon and carbon. A low corrosion rate in rapidly flowing brackish or seawater combined with excellent resistance to stress-corrosion cracking in most freshwaters, and its resistance to various corrosive conditions resulted in its use in marine applications such as valves & pumps (that are either submerged in sea water or frequently exposed to it), oil and chemical processing industries including non-oxidizing chloride solutions. The corrosion of a series of Copper and nickel alloys in natural sea water and in chloride solutions under different conditions are studied. Some authors have claimed that selective electrodissolution of nickel is predominant while others have found that copper dissolution depending on the composition of the alloy.

Inconel 600 wire- Excellent impact strength & mechanical properties

Inconel 600 wire is made from an alloy of nickel and chromium Inconel 600 that offers excellent resistance to oxidation & corrosion at high temperatures. This alloy can withstand heat and has good mechanical properties. This alloy has good workability & high strength.

Typical applications of this alloy are

·        Chemical processing

·        Nuclear engineering

·        Furnace components

·        Food processing

The high nickel content provides the alloy resistance to corrosion by many organic & inorganic compounds. Nickel also provides immunity to chloride-ion stress corrosion cracking. Chromium has resistance to sulfur compounds and oxidizing conditions at high temperatures or in corrosive solutions. This alloy is not precipitation hardenable and is hardened & strengthened by cold work. Inconel 600 alloy is used in various applications involving temperatures from cryogenic to above 2000°F.

Chemical industry

Inconel 600 alloy is used in the chemical industry due to its corrosion resistance and strength. Applications in chemical industry are

·        Bubble towers, heaters, stills & condensers for processing of fatty acids.

·        Equipment for handling abietic acid in the manufacture of paper pulp.

·        Tube sheets, evaporator tubes & flaking trays for the manufacture of sodium sulfide.

Heat-treating industry

Inconel 600 alloy is used in the heat-treating industry due to its strength & oxidation resistance at high temperatures. It is useful for muffles, retorts, roller hearths, heat-treating baskets & trays and other furnace components.

Aeronautical industry

Inconel 600 alloy is used in the aeronautical field for various engine & airframe components that withstand high temperatures such as exhaust liners, lockwire & turbine seals.

Electronic industry

Inconel 600 alloy is used for parts such as thyratron grids, springs, cathode-ray tube spiders and tube support members in the electronic industry.

Nuclear applications

 This alloy is a standard material of construction for nuclear reactors and has good resistance to corrosion by high-purity water and there is no chloride-ion stress corrosion cracking in reactor water systems.

Mechanical properties

Inconel 600 alloy can be hardened & strengthened in a broad range depending on the form & condition. This alloy exhibits moderate yield strengths of 25,000 to 50,000 psi in the annealed condition. Yield strengths in that range, combined with elongations of 55 to 35% allow the alloy to be fabricated. Heavily cold worked material can have tensile strengths of up to 220,000 psi.

Impact strength

Inconel 600 alloy has excellent impact strength at room temperature and retains virtually all of that strength at low temperatures. There is no tough-to-brittle transition with decreasing temperature.

Microstructure

Inconel 600 alloy is a stable & austenitic solid-solution alloy and the only precipitated phases present in the microstructure are titanium carbides, titanium nitrides and chromium carbides. Titanium nitrides & carbides are visible in polished microspecimens at magnifications of 50X or greater. Their appearance is as small, randomly dispersed & angular-shaped inclusions. There is a color difference as orange-yellow for the nitride & gray-lavender for the carbide. These nitrides & cyanonitrides are stable at temperatures below the melting point & are unaffected by heat treatment. Chromium carbides precipitate out of the solid solution at temperatures between 1000°F & 1800°F and the precipitation occurs at the grain boundaries & in the matrix.

Inconel wire- Optimum performance in high temperature conditions

Inconel alloy is a nickel-chromium alloy that has resistance to caustic corrosion, oxidation at high temperatures, ultra-high purity water corrosion & stress corrosion cracking. Applications of Inconel alloy are in

·        Nuclear engineering

·        Furnace components

·        Sparking electrodes

·        Food processing

·        Chemical processing such as reaction vessels, transfer piping, heat exchangers and evaporators.

·        Air pollution control such as dampers, stack liners, fans, ducts, stack-gas reheaters, housings and scrubbers.

Inconel wire is preferred for various applications such as

Rapid temperature changes

Inconel wire has high oxidation resistance at low/high temperature conditions, therefore, a single basket made of Inconel can be used in processes where temperatures change between near-cryogenic lows & heat treatment highs. Inconel is highly useful for manufacturing processes that combine high & low temperature processes in rapid succession.

Jet engines

Various manufacturing units use Inconel alloy in the construction of Jet engines and turbines. Jet engines need to withstand low & high extreme temperatures frequently during use. At 36,000 ft., the average air temperature is -56.3°C and the combustion process can exceed temperatures of 1,150°C as per the meteorology training website. Inconel retains tensile strength & oxidation resistance during rapid changes in temperature in the combustion process and cooling technologies used in the aerospace industry to rapidly reduce temperatures. Inconel is suitable for chemical resistance & extreme temperature conditions. Inconel is especially suitable for processes in which temperature elevations would normally reduce the oxidation resistance of other metals.

Heat treat applications

Inconel has resistance to extreme temperatures and retains a good amount of tensile strength at high temperature to continue holding moderate loads. Inconel is suitable for heat treat applications as it won’t lose shape easily when holding parts through a rigorous heat treat application.

Saltwater applications

Inconel has excellent resistance to sodium chloride (salt) at different temperatures, therefore, it is used in marine applications. Inconel is suitable for part washing basket in processes that use salt or in factories located near the ocean. Stainless steel alloys also have resistance to salt water however Inconel alloy is preferred for high temperatures.

Corrosion resistance

Inconel alloys are resistant to various types of corrosive media such as alkalis, moisture, salt solutions, non-oxidizing acids & organic acids. Stress corrosion cracking doesn’t occur and this alloy has a small tendency to selective corrosion. Pitting corrosion rarely occurs and this alloy has resistance to gases such as chlorine, hydrogen fluoride, carbon dioxide, hydrogen chloride, oxygen & sulphur dioxide. No heterogeneous structure occurs in these alloys as copper & nickel form a continuous series of solid solutions. Inconel alloy has excellent resistance to hot seawater at high flow rates. This alloy remains stable up to a moderate flow rate of 6m/s.

Inconel is alloyed, processed & melted using special designs to have excellent resistance to low-cycle & thermal fatigue at temperatures up to 1200°F. Inconel is used in various types of process or transport piping in Aircraft exhaust, automotive flexible coupling bellows & expansion joints. Inconel is also designed for excellent corrosion resistance in severe environments in pollution control, industrial/municipal waste treatment, chemical processing, pulp/paper production.