Specialist Castings have over 30 years experience in manufacturing and supplying anodes for cathodic protection.  Our range of anodes includes various specifications of both impressed current protection and sacrificial anodes.

We produce an extensive range of standard anodes and have the ability to produce non-standard items to exact specifications.

All of our anodes are produced according to the strictest quality and traceability guidelines and international standards. Whether to ASTM standards, British standards, European standards or International standards, the foundry manufactures to these standards and also carries out testing to these International standards. Whether it is chemical certificates from NAMAS approved testing laboratories, or G97 accelerated corrosion tests from USA laboratories or X-ray testing of anodes to ASTM E184 or other criteria, we ensure we operate at the highest quality levels required of the worldwide marketplace. We are currently, for instance, the only fully approved Chinese supplier of Magnesium anodes to Aramco and we have 4 spectrometers for silicon iron alone, as well as 2 spectrometers for Magnesium testing and we are still currently expanding these testing and inspection facilities.

We pride our selves on the quality of our products and adhere to strict processes throughout the production process, to ensure full transparency and traceability of our products.

Anode

What is Cathodic Protection?

Cathodic Protection is a method that is employed to limit or control the corrosion of a metal. In particular metal surfaces that are constantly exposed to highly corrosive environments, such as underground oil or gas pipes, or ships.

It is an electro-chemical method and works by making the metal to be protected the cathode of an electrochemical cell. The metal to be protected is forced to become “cathodic” in character by the anode that consequently becomes “anodic” in character, by the anode which consequently works by offering itself as “sacrificial metal”, thus defending the metal to be protected.   In short, the sacrificial metal (or anode) corrodes instead of the metal being protected.  There are two primary methods of cathodic protection; sacrificial protection and impressed current protection.

With sacrificial cathodic protection, polarisation of the structure to be protected (the cathode) is caused by the electron flow from the anode to the cathode, so the two metals must have a good electrically conductive contact. The driving force for the cathodic protection current is the difference in electrode potential between the anode and the cathode.  These systems are stand alone and do not require an additional electrical source. Types of sacrificial anodes include magnesium anodes, aluminium anodes, water box anodes and zinc ribbon anodes.

In an impressed current protection system, an external source of electric current is used to help drive the protective electrochemical reaction.

This type of approach is more often used for larger structures, or where electrolyte resistivity is high and galvanic anodes cannot economically deliver enough current to provide protection.  Anodes used in this type of cathodic protection include silicon iron anodes, mixed metal anodes and, occasionally, graphite to titanium anodes.  The most commonly used impressed current anodes are silicon iron tubular anodes, silicon iron solid (or stick anodes and MMO anodes.

Magnesium Anodes

Magnesium Anodes are a type of Sacrificial Anode. They are mainly used in seawater, brackish water, and fresh water cathodic protection systems. They are very effective and economical corrosion protectors of steel structures and have been recognised in this field for over 25 years. Magnesium …

Aluminium Anodes

Aluminium Anodes are another type of Sacrificial Anode that, although they have a lower voltage rate than magnesium anode, they have a much slower consumption rate than magnesium or zinc, and are ideally suited for seawater applications though can be used in …

Water Box Anodes

Water Box Anodes are another type of Sacrificial Anode. They are an important component as their purpose is to protect metal tanks from corrosion. Magnesium and Aluminium anodes have high surface and length ratios in relation to cross sectional size. This allows …

Zinc Ribbon Anodes

Zinc Ribbon Anodes are another type of Sacrificial Anode and are an enhanced flexibility product extruded by 99.99% high pure zinc material. They provide a very simple, cost effective, maintenance-free method of corrosion control. These anodes are especially useful for unattended applications …

MMO Anodes

Mixed Metal Oxide Anodes (MMO Anodes), also called dimensionally stable anodes, are a type of Impressed Current Protection Anode, consisting of rare earth oxides coated onto a titanium substrate.  We are able to supply the MMO anode material available in rod, …

Tubular Anodes

Tubular anodes have dense small projections throughout the entire anode surface so they can provide at least 20% more surface area than other conventional anodes. The increased surface area means low current density at certain current out or higher current out …

Stick Anodes

Solid Stick Anodes are a type of Silicon Iron Anode and are chill cast in metal moulds. This guarantees a rapid solidification as chill-casted anodes have excellent grain structure than normal sand cast anodes which provide better performance to corrosion protection. As …