Sintered mesh elements for high temperature and corrosive environmental applications

sintered mesh

Sintered mesh materials are normally made into tubular shapes preventing the need for a core. Tubular shapes can also be considerd as candles instead cartridges, a single element in the house called a cartridge and a multi-element housing called a candle filter.

The mesh elements are sintered to receive suitable pore size and filtration properties. These elements are made in specially designed moulds and various shapes are feasible. The mesh elements are used for compressed air filtration and other applications in environments where temperatures vary.

Sintered mesh filters offer the feasibility of closer control of hole size, shape and uniformity resulting in very strong, rigid and highly resistant to heat screen. The hole sizes vary from submicrometre dimensions up 1mm. So practically, ultrafine filtration needs can be met by using sintered metal mesh elements.

Porosity to overall matrix volume can be controlled over a large range by using sintered metal element. Whilst increasing the porosity results into reduction of resistance to through-flow, the matrix strength decreases at the steep rate. To receive suitable mechanical strength, it is essential to restrict porosity by suitable management of strength-permeability needs. For filter elements, the porosity ranges up to 70% or may be higher for low pressure drop screens. The specific benefit of sintered mesh elements besides of fine cut-off that can be received, is high strength, durability that makes them a suitable choice for high pressure applications.

Sintered metal mesh filters are categorized into- element made by sintering loose powder in a mould, and those developed by compaction. Spherical particles for more uniform packing and hence possess more uniform hole sizes. Spherical particles are easier to fabricate and categorize by spray atomization and sieving. The coarse grades of sintered metal filters are made from particles with a particle diameter up to 1 mm. As the pore size is often about 15% of the particle diameter, it results into a pore size of 150 micro-m. These sintered mesh screens are costly to fabricate and hence not competitive at this level with wire mesh screens. Production costs of sintered mesh screens are less with smaller diameters although the cost of woven mesh screens increases with reduction in hole size, while mesh strength and durability is affected.

Sintered mesh screens for high temperatures and high pressure environments are made from stainless steel, Monel, pure nickel, Hastelloy and tungsten. Cupro-nickel sinter easily at low temperatures and hence a whole range of shapes can be developed directly from mesh. The screens can be machined to closer tolerances than developed by direct moulding.

Sintered mesh elements offering high strength are used in applications that demand high strength, higher resistance to temperature and outstanding resistance to corrosion. The sintered mesh elements are commonly made in the form of plates or discs for direct use in filter construction. Sintered mesh screens made from Inconel, Hastelloy and other high performance alloys are used in applications that involve vigorous corrosion and high temperatures.