MMO Anodes
Thursday, 21 February 2019 00:00MMO ANodes ( Mixed Metal Oxide Anode )
MMO anodes are made up of two parts of base metal and coating. Titanium is used as a base metal because of required properties to absorb coating in order to stand against aggressive chemical environments. Also, it is suitable for flow transfer. Other advantages of titanium are its use in various shapes, including pipe, ribbon, wire, mesh and plate.
Coating of MMO anodes is very thin layer (few microns) so that it can be applied on the base metal in a variety of ways. Depending on the application, this coating can be a combination of two or more metal oxides such as oxides of iridium, tantalum, ruthenium and titanium
Cross section of MMO Anodes
the additional potential for releasing chlorine and anodic oxygen decreases significantly By applying this coating as an activating agent, since Catalytic coating of MMO anode produces a slight resistance for anode which causes to lower consumption rate by considering the life time of anode. MMO anodes have a very low consumption rate of less than 1 mg / A.Year depending on environmental conditions and application.
Microscopic structure of coating of MMO anodes
The maximum output current density and lifetime of MMO anodes in differnet environmental conditions are as follows:
Environmental conditions |
maximum output current density (A/m2) |
Life Time (Year) |
Carbon backfill | 50 | 25 |
petroleum coke | 100 | 25 |
freash water | 100 | 25 |
saline water | 300-100 | 25 |
sea water | 600 | 25 |
heat treatment furnace of MMO anodes
generally, MMO anodes have the following benefits:
• Easy to use
• Possibility of manufacturing anodes with different shapes
• Easy to Handle and Install
• Light weight
• High Output current
• Long lifetime of anode in very high current density
• Dimensional stability
• Ability to renewing of anode coating
• Reliability
These anodes are used in imperessed current cathodic protection systems in order to prevent corrosion of metal structures. The most common application of these anodes is the maintenance and repairment of some structures such as bridges, marine structures, offshore platforms, storage tanks, buried pipelines in soil or immersed in
.water and concrete structures
sample of cathodic protection mmo anodes in BORNA Godaz company
:The most common shapes of cathodic protection MMO anodes in bronagodaz are as follows
- Tubular MMO anodes
.Tubular MMO anodes are used for cathodic protection of buried metal structures in soil (directly or together with carbon backfill) or immersed in water
Sample of BORNA Godaz tubular mmo anodes
Titanium substrate of These anodes are based on the requirements according to ASTM B338 Grade 1 or 2 standard. So, output current and lifetime of tubular MMO anodes according to the size and environmental conditions are as follows:
Environmental conditions |
Anode dimension (lenght ×Diameter) |
Output current (A) |
Life time (Year) |
Soil, Coke and salt water | (in 48 × in 3.4) 1220 mm× mm 19 | 7 | 25 |
(19.7 in × in 1) 500 mm × mm 25 | 4 | 25 | |
( 39.4 in× in 1) 1000 mm × mm 25 | 8 | 25 | |
(in 48 × 1 in) 1220 mm × mm 25 | 3.5 | 25 | |
(60 in × 1 in) 1500 mm × mm 25 | 4.5 | 25 | |
(48 in× 1.25 in) 1220 mm × mm 31.75 | 12 | 25 | |
Sea water | ( 48 in× 3.4 in) 1220 mm × mm 19 | 45 | 25 |
(19.7 in × 1 in) 500 mm × mm 25 | 25 | 25 | |
( 39.4 in× 1 in) 1000 mm × mm 25 | 50 | 25 | |
(48 in × 1.25 in) 1220 mm × mm 31.75 | 75 | 25 |
Ribbon MMO anodes
Ribbon mmo anodes are used for cathodic protection of pipelines and tanks. Titanium base of These anodes are choosed on the requirements of the ASTM B265 Grade 1 standard
sample of BORNA Godaz ribbon mmo anodes
Dimensions, weight of ribbon MMO anodes, maximum current density and lifetime of these anodes are as follows:
width | (0.25 in) 6.35 mm |
thickness | (0.025 in) 0.635 mm |
Coil lenght | 100 m |
Weight lenght | 1.5 kg |
Region surface of ribbon | 0.014m2 Per/m |
Environmental condition |
Output current (mA/m) |
Approximate Life time (Year) |
Fine sand | 42 | 50 |
Concrete | 1.5 | 100 |
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- Mesh-Ribbon MMO Anodes
Mesh-Ribbon MMO anodes are used to cathodic protection of concrete structures. Titanium substrate of These anodes are choosed on the requirements
پهنا (mm) |
جریان خروجی (mA/m) |
طول عمر تقریبی (Year) |
10 | 2.75 | 75 |
13 | 3.7 | 50 |
3.5 | 100 | |
15 | 4.1 | 50 |
3.9 | 75 | |
20 | 5.6 | 50 |
4.9 | 75 | |
4.7 | 100 |
- Wire MMO anodes
Sample of BORNA Godaz wire mmo anode
Titanium substrate of These anodes are based on the requirements according to ASTM B863 Grade 1 or 2. The output current of wire MMO anodes according to their dimensions are as follows:
Dia. wire (mm) |
Output current (A/m) | ||
Sea water | Salt water | Carbon backfill | |
1.5 | 3 | 0.5 | 0.5 |
2 | 4 | 0.66 | 0.66 |
3 | 6 | 1 | 1 |
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- Mesh MMO anodes
Mesh mmo anodes are usually used to cathodic protection of concrete structures.
Also, BORNA Godaz company has the ability to manufacture various types of MMO anodes according to customer enquiry such as disc, probe, plate and etc.
It should be noted that probe anodes are used in impressed current cathodic protection systems for water boxes, internal surfaces of pipelines, vessels and other industrial applications.
Also, Several common experiments are carried out on mixed metal oxide anodes in our company by corrosion experts, which are as follows:
Eye Examination Test, Electrochemical Test according to NACE TM-0108 and IGS-M-TP22 standard, Galvanic Potential Test according to ASTM-G 71, Pilot cathodic protection test, Electrical resistance of joint position , Investigation of MMO coating adhesion to titanium substrate according to ASTM-D 3359 and IGS-M-TP22 standard.
BORNA Godaz company is proud to receiving credible certificates in the field of quality assurance and sales of mixed metal oxide anodes from various companies and laboratories such as: National Iranian Gas Co., Iranian Offshore Oil Co., Pars Oil & Gas Co., Amir Kabir Color Research Co., Corrosion Laboratory of Tarbiat Modarres University, Iranian corrosion association and etc.
The following documents show typical datasheets of MMO (Mixed Metal Oxide) anode made in BORNA Godaz company. Also, Other informations such as ITP, QCP, OPC, chemical and electrochemical reports according to NACE TM0108 and certificates have shown here.
Technical Documents of BornaGodaz MMO Anode
Datasheet Sample of BornaGodaz Tubular (String type) MMO Anode
Datasheet Sample of BornaGodaz Ribbon MMO Anode for cathodic protection of pipelines and tanks
Chemical Analysis & ALT Test Report of BornaGodaz Wire MMO Anode
Chemical Analysis & ALT Test Report of BornaGodaz Ribbon MMO Anode
Manufacture Approval of BornaGodaz MMO Anode by IOOC Company
Inspection Release Note of BornaGodaz Tubular MMO Anode by POGC Company
BornaGodaz MMO Anode Catalogue - Persian Version