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  Mixed Metal Oxide Anodes

Mixed Metal Oxide Anodes are dimensionally stable in all environments. To obtain the highest level of protection from an impressed current cathodic protection system you need an anode with a very low consumption rate and high current capacity. With Borui’s tubular mixed metal oxide line of anodes you get powerful protection and unsurpassed stability. The anodes are made using tubular titanium substrates which are coated with a mixed metal oxide catalyst. The catalyst is thermally applied to the titanium to form an extremely chemical resistant bond. This special chemical composition brings together the stability of titanium with the conductive properties of the mixed metal oxide catalyst to achieve superior performance. In soil and fresh water applications the anodes have a recommended current density of approximately 100 A/m2, and can be operated over 600 A/m2 in seawater environments. Even at these relatively high discharge levels the anodes will be consumed at less than 1.0 mg/Amp-yr.

  The tubular design of these anodes also allows for numerous performance benefits. The tubular configuration provides a larger surface area, which in turn permits greater current output and lower anode to earth resistance. The tubular style also means lead wire connections can be made in the centre of the anode. With Borui’s tubular anodes this connection consists of two half bracelet lead slabs which grip firmly to the internal circumference of the anode and copper conductor. This connection is protected from moisture intrusion by epoxy which fills the entire anode tube. The ends of the anode are then covered with shrink tubing for a completely sealed electrical connection.

TYPICAL  APPLICATIONS

Mixed metal oxide anodes have proven to operate effectively in all types of environments, including areas with extremely low pH levels (under 1), and high chloride concentrations. While Borui’s tubular anodes can be used singularly, their unique configuration also makes them ideal for use in strings on offshore platforms or in deep groundbeds. In addition, the string anodes can be installed parallel to transmission pipelines, or used for other special applications.

TECHNICAL SPECIFICATIONS

MMO coatings are generally offered on titanium substrates to ASTM B265 Grade 1 or 2 for sheet, strip and mesh; ASTM B348 Grade 1 or 2 for rod and wire products; and ASTM B338 Grade 1 or 2 for tubular products.

  Millions of people worldwide enjoy swimming pool activities every year. Traditionally, chlorine-containing chemicals forming hypochlorous acid have been used as the sanitizing agent. Currently, a new way to produce hypochlorous acid has been developed from industrial technique known as the Chlor-Alkali Process. Using an electrolytic cell,a current is passed through the NaCl solution liberates chlorine ions, Cl- , at the anode, and hydroxide ions, OH- , at the cathode. Chlorine produced from the electrolytic cell reacts with water in the same way as conventional chlorine containing chemicals. The products are chlorine ions, hydrogen ions, and hypochlorous acid. The use of a salt chlorination system reduces the rate of corrosion of pool equipment and bleaching of swimsuits. There is less irritation to skin due to softer water.

  Suzhou electrode offers ruthenium/iridium oxide coated DSA titanium anode for swimming pool water disinfection electrolytic chlorinator cell. The MMO coating of the titanium anode is optimized for maximum chlorine production, with excellent coating strength and adherence to the substrate for longer service life.

  Cathodic protection (CP) is a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical cell[1]. The simplest method to apply CP is by connecting the metal to be protected with another more easily corroded metal to act as the anode of the electrochemical cell. Cathodic protection systems are used to protect a wide range of metallic structures in various environments. Common applications are; steel, water or fuel pipelines and storage tanks; steel pier piles; ships and boats; offshore oil platforms and onshore oil well casings and metal reinforcement bars in concrete buildings and structures.

  Suzhou Borui electorde supply professional CP sverice and anode, such as: MMO coated titanium wire anode, MMO coated titanium tublar anode.

The mixed metal oxide of Lida or Telpro anodes has a low consumption rate, measured in milligrams per ampere-year. As a result, the dimensions remain nearly constant during the life of the anode, providing a consistently low resistance. Whether operating in soil, freshwater, mud or seawater, mixed metal oxide coatings demonstrate high chemical stability, even in environments with low pH values. Unlike other impressed current anodes, MMO coatings are not affected by the generation of chlorine.

Tubular Anodes
Mixed Metal Oxide (MMO) tubular anodes are titanium tubes with a mixed metal oxide coating. The mixed metal oxide is a crystalline, electrically-conductive coating that activates the titanium and enables it to function as an anode. 

Anode Strings
An MMO “anode string” is comprised of electrical cable threaded through one or more tubular anodes. Electrical connection between the anode and cable is via a patented crimping process. The crimp connection seals the anode around the cable at both ends.

The terminal anode, the last anode on a string assembly, has a metal loop for attaching a weight. Since only a single cable lead protrudes from the hole, the junction box is eliminated when using a MMO string – reducing the cost of materials and labor. String assemblies are also available in a looped configuration with two tails, or as multiple, staggered strings for system redundancy and maximum current distribution throughout the ground bed. Like any impressed current anode, proper ground bed design is paramount to optimum, low resistance performance. MMO anode manufacturers recommend quality conductive, carbonaceous back fill, a vent pipe and Centralizers, suitable cable, and good design practices.

Cable Selection
MMO manufacturers recommend dual-insulated cable, such as PVDF/HMWPE cable for use where anodes operate in ground beds high in chlorides. Where chlorides are not anticipated, such as shallow vertical and horizontal surface beds, an economical cable choice is HMWPE.  The high current capacity (150 amps) and flexibility of the EPR/CSPE cable makes it ideal for seawater applications. EPR/CSPE is not recommended for ground bed applications where chlorides are present (e.g., deep anode ground beds).

MMO Wire Anodes
MMO wire anodes are copper cored titanium wire with mixed metal oxide coating. The mixed metal oxide is a crystalline, electrically-conductive coating that activates the titanium and allows it to act as an anode.

MMO Disk Anodes
The MMO Disk Anode was developed for cathodic protection of dam and navigation lock gates. Since our disk anodes are designed to operate in fresh, brackish and seawater environments, other suitable applications include: marine structures, water tanks and vessels. With an optional primary seal spacer gasket, it can be used on the inside of pipes, tanks, or other curved surfaces. The active element in the Disk Anode is a 6″ diameter x 1/8″ thick titanium disk with a mixed metal oxide coating. When applied on titanium, the MMO coating has an extremely low consumption rate, measured in terms of milligrams per year. As a result of this low consumption rate, the dimensions of the anode remain nearly constant throughout the design life.

The mixed metal oxide coated disk is secured into a 12″ diameter x 1/8″ thick dielectric shield made of a durable, chlorine resistant, molded FRP-vinyl ester. This FRP shield has been designed to resist damage from floating debris and ice, as well as serving to enhance the current throwing capability of the disk. The shield also minimizes excessive current damage to the coating on surrounding steel. The low profile Disk anode fits flush with the surface, so total protrusion from the steel bulkhead is a mere 1/2″.

The coated titanium disk and shield assembly is attached to a 1-1/4″ diameter FRP stud via an interlocking epoxy joint. This joint enhances torque capability and subsequent sealing. A 100% compressible EPDM elastomeric o-ring molded into the shield assures a watertight seal between the disk and steel bulkhead, while simultaneously allowing the shield to fit flush against the bulkhead. Rod threads are platinum plated to prevent oxidation of the titanium-providing a low and constant contact resistance over the life of the anode. Nickel plated brass nuts further ensure a reliable, low resistance contact. And to prevent crevice corrosion of the titanium disk, a special, mixed metal oxide coating has been applied on the edges and back.

Condenser anodes are available either bare, coated with a plastisol (PVC) coating or with a specially designed molded Polypropylene box used to improve current distribution and increase the effective life of the anode.

Platinum is  a precious metal haveing very good of pysical and chmical properited,such as:

• high corrosion resisitance
• thermal conductibity
• catalytic nature

As it is very ecpensive, so we develop platinized anode as substitue

Platinized anodes is made up of substrate material and platinum plated on the substrate material. Platiized anode intergrates good physical and chemical properties of platinum and titanium.

Substrate materila can be TITANIUM, TANTALUM, NIOBIUM. So the platinized anodes are called as:

• Platinized titanium anode
• Platinized tantalum anode
• Platinized niobium anode

They can be in shape of mesh, plate,  rod,  tube and other complex shape.Mesh and plate are normally in plating, electroanalysis and watertreatment. Rod and tube normally use in cathodic protection.

Suzhou Borui platinized anode is manufactured by electroplating, We have leading plating technology in whole word. Our platinized anode are very smooth on anode surface and can be nice substitue of pure platinum anode. The purity of platinium coating is 99.99%. We supply design, manufacuring, recoating and repair service.