How long has copper plumbing been used?

The earliest recorded use of copper for conveying water is a water conduit in Abusir, Egypt, which dates back to 2750 BC and is still in a good state of preservation. Copper water pipes and cisterns were widely used by the Romans – examples can be found at the archaeological site of Herculaneum, destroyed by the eruption of Vesuvius in 79AD. At the beginning of this century, copper started being used again in Europe and North America.

How many copper alloys are available for aquaculture so far?

Three. They are: Copper-Zinc, Copper-Nickel, and Copper-Silicon.

How much do copper alloy cages cost?

The exact cost of using copper alloys in aquaculture enclosures depends on multiple factors such as the cage size and the transportation of materials to the building site, and then of the cage to the farming site.  Overall, the total cost is offset by the long-term cost savings associated with longer service life, decreased fish losses, lowered maintenance, etc.

Is it possible to heat treat aluminium bronze CW307G (CA104) to improve its corrosion resistance?

Yes, this is covered in Def Stan 02-833. For extruded rods and sections of size 40mm and below, an anneal at 740°C plus or minus 20° followed by air cooling is carried out. This mandatory heat treatment is to eliminate phases which are likely to give rise to selective corrosion in sea water.

What range of colours can be achieved with a finished bronze casting?

Using chemical treatment, any desired colour can be obtained. Specialist companies should be consulted to identify the correct product for a particular project.

What situation is each best for?

Copper-Zinc is good for flexible mesh containment systems.

Copper-Nickel is good for rigid (e.g. welded) mesh.

Copper-Silicon is good where rigid mesh is needed, or where panels can have flexible connections.

La bioincrustación es un grave problema en la acuicultura. ¿Las aleaciones de cobre eliminan toda la bioincrustación?

Las mallas de aleación de cobre inhiben de forma natural la bioincrustación, mejorando así el flujo y la circulación del agua, aunque no eliminan completamente el problema. Si se emplean en las condiciones apropiadas, las aleaciones de cobre muestran unos niveles muy reducidos de microincrustaciones y no muestran macroincrustaciones a lo largo de su vida útil; para esto sólo se necesita limpiar las jaulas una o dos veces al año.

What type of bronze is used for modern works of art?

Bronze has been used for centuries to create statues, and is still the first choice for modern, striking works of art. The most widely-used alloys for such objects are leaded gunmetals, such as CC492K and CC491K.

What type of copper is specified to make wire used to transmit electricity to trams, trolley buses or trains?

Pure copper is too soft for overhead wires and the copper alloys used are specified in BS EN 50149:2012. These are alloys of copper with respectively small amounts of silver, magnesium, tin or cadmium.

What types of cages can copper alloys be used for?

Copper alloys can be used for current cage designs as well as other future, more cost-effective designs and applications. Today, it can replace round HDPE cages, and square steel cages with and without platforms. Trials using the Aquapod 3600 and the OCAT cages with copper mesh are currently being conducted, and the Ocean Spar 3000 submersible cage is in prototype discussions.

What values of electrical conductivity can be obtained in high purity copper castings? Are they comparable to the values available for wrought copper?

Generally, the values of the International Annealed Copper Standard (IACS) are lower than those of wrought copper due to the presence of a small percentage of gas porosity and a small percentage of impurities such as iron.  A value of 93% IACS is guaranteed but, with a very low porosity and very pure copper scrap (such as that from busbars), a value up to 102% IACS may be obtained.

What are the benefits of flame-free jointing techniques?

Copper flame-free jointing can be done by press fittings and push-fit fittings. The benefits of these types of fittings are:

  • Work can be undertaken with occupants in the building
  • No flux fumes
  • No additional ventilation required
  • No need for hot work permits/certificates
  • Quick to install.