PRODUCT GUIDE – TEXTILE FILTRATION

Galvanised Steel or Iron Wire Mesh

Currently, filters made of galvanised steel or iron wire mesh are commonly used for low pressure or gravity filtration of aluminium die castings. Fortafix can provide these filters, and enquiries should be made through our contact page. There are a number of advantages to using galvanised steel or iron wire mesh. The metallic wire mesh filters are reasonably priced, have good strength, and are adaptable in terms of size and design.

There are some disadvantages too. When aluminium castings are processed via a metallic filter, a substantial amount of ferrous element is added, which reduces the mechanical strength of the castings, especially for high-quality standard castings. Also, risers containing metallic filters after solidification cannot be re‐melted directly in the furnace, even after special treatment. This increases waste.

Fibreglass Mesh Filters

Fibreglass mesh filters are used to enhance flow distribution, reduce turbulence, and filter non-ferrous alloys, particularly molten aluminium. Filters are made from E-glass fibreglass yarn with a range of finishes. Fiberglass Mesh Filters can be produced to many kinds of shapes according to clients’ requirements, such as: square, rectangle, round and fan.

There are some key advantages to fibreglass mesh filters.

• They are cost-effective with good performance.
• They are easy to install and use.
• Fibreglass fabric filters do not contaminate. This allows for in-house re-melting of the recycled sprue, gate or castings risers, without any additional treatment.
• Used filter material floats on top of recycled molten metal and can easily be scooped off.

Aluminium and alloy filtration application

For aluminium and alloy filtration, fibreglass mesh filters can be used across a number of applications. These include:

• DC casting, like ingots and billets
• Furnace, transfer or launder filtration
• Sand casting
• Permanent mould casting
• Shell mould casting
• Gravity die casting
• Low pressure die casting
• Investment casting

Available product forms

Having decided the purpose of the filtration, the physical form of the filter must then be decided upon. A number of options exist, including the following:

1. Cut pieces for in-mould casting filtration.
   • • Standard size of 300x300mm
     • Other sizes and shapes are available upon request including conical and moulded cups

2. Rolls for furnace spruce filtration for cutting into smaller sizes.

• • Soft without coating (original fabric)
  • Soft with coating (acrylic resin coating)
  • Rigid with coating (phenolic resin coating)
  • Width of roll can be 0.5m with lengths of 50-200m as required

3. Pre-sewn shapes for DC castings.

4. Moulded preformed shapes for investment casting, gravity casting and low pressure die casting.