Lida MMO Tubular Anodes by De Nora Tech

High Output, MIxed Metal Oxide Coating for Water & Soil C.P. Applications

 

Applications

Groundbeds

  • Deep
  • Shallow
  • Vertical
  • Horizontal
  • Open Hole

Marine

  • Sea Water
  • Brackish Water
  • Mud

Fresh Water



Features

  • Multi-anode conductor
  • Lightweight / durable
  • High current output
  • Patented crimp connections
  • Dimensionally stable 

Benefits

  • Dramatically reduces cable costs
  • Reduced handling and installation costs
  • Lower cost per amp
  • Guaranteed electrical contract and moisture seal integrity
  • Consistently low resistance anode 
     

Description

LIDA® anodes utilize an innovative and patented design: a titanium base with a mixed metal oxide conductive coating. This coating forms a solid solution with the titanium substrate and is an excellent electronic conductor.

The mixed oxides are formed on the surface through a process of thermal decomposition, creating an oxide film which is typically anhydrous and almost insoluble in acids. Thermal control of this process causes the mixed oxides to recrystallize, further increasing their chemical stability.

These anodes are often referred to as composite anodes. Physically, this term refers to a ductile, corrosion resistant base metal covered with the highly conductive stable film described above. The base metal, titanium, provides the required toughness for the system. The titanium substrate is classified as a "valve metal" or film forming metal. Such metals in their natural state are protected by thin, self-healing, tightly adherent oxide films which are acid resistant and resist the passage of current in the anodic direction. Thus, if an attempt is made to operate a valve metal as an anode, it is necessary to raise the potential of the valve metal surface to a high value in order to pass significant current through the anode.

Then, in order to use titanium as a realistic impressed current anode, the growth of the insulating oxide must be prevented. The electro-conductive film applied to the surface of titanium satisfies this requirement and permits the flow of electrical current at a low and steady voltage.

The wear rate of the LIDA® anodes is extremely low and uniform. The thickness of the mixed oxide film decreases linearly with time at all points on the surface. The wear rate of the anode is between 3 and 6 milligrams/ampere-year, and is constant over all current densities in general or frequent use.

De Nora LIDA® anodes are resistant to abrasion with a hardness of approximately 6 on the Mohs scale. De Nora mixed metal oxide anodes are available for soil, fresh water, mud and seawater environmently. These anode systems function reliably in cathodic protection systems in the soil as deep well or shallow groundbeds as well as in natural water applications.

LIDA® anodes for soil application are available in two lengths, and two diameters, to meet a range of current output requirements: 50 and 100 cm (20 and 40 inch) and 2.5 cm (1.0 inch).

They are available as a single-unit assembly, or as a multi-unit assembly on a single cable. De Nora wire or tubular anodes are also available as canistered anodes, surrounded by carbonaeous backfill to minimize installation time and handling on site. De Nora mixed metal oxide anodes are also available in wire, rod, mesh, ribbon, and disc form for a variety of impressed current CP applications.

According to OSHA Regulations, the precious metal coating and the substrate to which it is applied constitute and "Article." An "Article" is defined as being a manufactured item which is formed with specific shape or design during manufacture which has end-use function dependent in whole or in part upon its shape or design during end-use and which does not release or otherwise result in exposure to a hazardous chemical under normal conditions of use.

An "Article" is specifically excluded from the scope of the Hazard Communication Rule. As such, no MSDS would be required for sale of coated substrates. 

Reliability

In choosing the De Nora LIDA® tubular anode, you have selected the most durable and reliable product in the industry for your cathodic protection needs. De Nora LIDA® tubular anode strings are backed by a five-year, no hassle warranty. Design, assembly and installation factors have been carefully considered so that your time and costs are minimized as much as possible.

SavingsEase of Installation

  • In many cases, De Nora LIDA® mixed metal oxide tubular anodes offer savings of 15 - 35% over competitive anodes on an installed cost basis.
  • De Nora LIDA® anode-cable assemblies are easy to handle, transport and install because of their unique flexibility. It makes your job on-site easier as well.

Quality Assurance

From the application of the coating to the design of the shipping crate, De Nora's attention to quality sets these anodes apart. The coating undergoes stringent quality control examination by SEP, X-ray and adhesion test methods throughout the coating process to assure proper thickness and application. Anode strings are 100%t tested for the quality of electrical conductivity and integrity of the seal. Personal attention to each detail of the quality control process assures you a superior, reliable product. De Nora offers one of the best anode warranties available.

Special Services

Farwest offers groundbed design services to customers. Our experienced personnel can assist you in designing the most efficient, cost-effective approach for many unique applications.

LIDA Crimp  

Anode to cable sealing at each end
  • Both ends of the tubular anode are sealed over the insulated cable by applying 50 tons of hydraulic pressure. This crimping process eliminates the need for mastic or resin sealants.

Anode-to-cable electrical connection at center
  • Electrical connection between the tubular anode and the power cable wire is achieved by sliding the tube onto the cable and crimping a section of the tube at mid-length around a stripped portion of the cable.

Many impressed current anodes are connected to the cable with resin-based seals which may develop cracks or lose adhesion to the cable or anode. Moisture penetration also may occur, resulting in loss of electrical contact. De Nora LIDA® anodes are connected with a special crimping process which improves the life of the tubular anode system. On the surface, the crimp on the ends and in the middle appear the same. Yet they serve different purposes and are made differently. The center crimp makes electrical contact with the cable while the end crimps form a moisture-resistant seal.

Tubular Anode Dimensions

AnodeDiameterLengthWeightSurface
Area
2.5/50 1.00"
2.5 cm
19.7"
50 cm
0.40 lbs
0.18 kg
0.42 ft2
0.039 m2
2.5/100 1.00"
2.5 cm
39.4"
100 cm
0.77 lbs
0.35 kg
0.84 ft2
0.079 m2

TTubular Anode Cable Selection
 

De Nora recommends dual-insulated cable, such as PVDF/HMWPE cable for use where anodes operate in groundbeds high in chlorides - resulting in chlorines gas generation. 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 Exane Rig cable makes it ideal for seawater applications.

LIDA® Tubular Cable Recommendations
 
Type Wire
Size
Nominal
Weight Length
kg/m lbs/ft
Outer
Jacket
Inner Jacket Max
Current Output
Features
HMWPE #8
#6
0.13 0.09
0.18 0.12
HMWPE
HMWPE
none
none
27
50
Economical
PVDF/
HMWPE
#8
#6
0.13 0.09
0.18 0.12
HMWPE
HMWPE
none
none
27
50
Chlorine-resistant
Exane Rig Cable 4/0
0..90 0.61
Exane irradiated
cross-linked
polyolefin
none
560
Highly Flexible
High Current Capacity

MAXIMUM RATED CURRENT OUTPUT
as a function of DESIGN LIFETIME

De Nora LIDA® Tubular Anode Specifications

Application
Anode Type
Life
Maximum Rated Output
Temp Amps Temp Amps
 Coke (Soil)
FW/ST 2.5/100
20
  
11.0
     
FW/ST 2.5/50
20
  
5.5
     
 Fresh Water
FW/ST 2.5/100
20
above 5° C
(40° F)
13.5
below 5° C
(40° F)
9.5
FW/ST 2.5/50
20
6.8
4.8
 Brackish Water
FW/ST 2.5/100
15
above 5° C
(40° F)
20
below 5° C
(40° F)
14.0
FW/ST 2.5/50
15
10
7.0
 Mud
 Fresh or
 Brackish
MT/ST 2.5/100
15
above 5° C
(40° F)
11.2
below 5° C
(40° F)
7.8
MT/ST 2.5/50
15
5.6
3.9
 Seawater
SWT 2.5/100
15
above 10° C
(50° F)
37.5
below 10° C
(50° F)
26.3
SWT 2.5/50
15
19.0
13.3
 Mud - Saline
MT 2.5/100
15
above 10° C
(50° F)
18.8
below 10° C
(50° F)
13.2
MT 2.5/100
15
9.5
6.7

DDe Nora LIDA® Advantage

De Nora LIDA Crimp

Many impressed current anodes are connected to the cable with resin-based seals which may develop cracks or lose adhesion to the cable or the anode. Moisture penetration also may occur, resulting in loss of electrical contact.

De Nora LIDA anodes are connected with a special crimping process which improves the life of the tubular anode system. On the surface, the crimp on the ends and in the middle appear the same. Yet they serve different purposes and are made differently. The center crimp makes electrical contact with the cable while the end crimps form a moisture-resistant seal.

Electrical connection between the tubular anode and the power cable wire is achieved by sliding the tube onto the cable and crimping a section of the tube at mid-length around a stripped portion of the cable.

Both ends of the tubular anode are sealed over the insulated cable by applying 50 tons of hydraulic pressure. The crimping process eliminates the need for mastic or resin sealants.

Reliability

In choosing the De Nora LIDA tubular anode, you have selected the most durable and reliable product in the industry for your cathodic protection needs. De Nora LIDA tubular anode strings are backed by a five-year, no hassle warranty. Design, assembly and installation factors have been carefully considered so that your time and costs are minimized as much as possible.

Savings

In many cases, De Nora LIDA mixed metal oxide tubular anodes offer savings of 15-35% over competitive anodes on an installed cost basis.

Ease of Installation

The De Nora LIDA anode-cable assemblies are easy to handle, transport and install because of their unique flexibility. It makes your job on-site easier as well.

Special Services

De Nora offers groundbed design services to our customers. The company's experienced personnel can assist you in designing the most efficient, cost-effective approach form many unique applications. De Nora also offers a design software package which is available at no cost. Customers find it helpful in designing groundbeds in a wide range of applications.

Quality Assurance

From the application of the coating to the design of the shipping crate, De Nora's attention to quality sets us apart. The coating also undergoes stringent quality control examination by SEP, X-ray and adhesion test methods throughout the coating process to assure proper thickness and application.

Anode strings are 100 percent tested for the quality of electrical conductivity and for integrity of the seal. The leakage test uses helium and a special detector to confirm the integrity of the seal. Each and every electrical connection is checked by applying 20 amps and measuring the voltage drop. Our personal attention to each detail of the quality control process assures you of a superior, reliable product.


Tubular Anode Guidelines for Use

In groundbed design, it is important to remember that the purpose of the tubular anode is to provide current to the coke breeze column. Good design of a groundbed begins with first sizing the diameter and depth of the coke breeze column (active depth).

Parameters important to consider in the design are:

  • Backfill current density. This value is the groundbed current divided by the surface area of the backfill column that contacts the soil. In most deep groundbeds, this value should not exceed 100 - 200 mA/ft2.
  • Coke breeze resistivity. Use a realistic value based on experience in the area or obtain advice from the supplier.
  • Average soil resistivity
  • Soil strata makeup. What is the water table depth ?
  • Groundbed current.
  • Chemical contact of groundwater or moisture. Is chloride salt likely to be present?

     

Ventralizers™

For optimum performance, Ventralizers should be used to assure that the tubular anodes will be located in the center of the groundbed. The Ventralizer's unique design further allows the operator to attach the anode to the vent pipe - providing 1" of separation between the anode and vent pipe. Standard sizes are 6", 8" and 10", suitable for hole sizes ranging from 6" to 12".

Vent Pipes

Vent pipes should be used in all deep groundbeds. The importance of vent pipes includes.

  • Removal of gases generated downhole.
  • Providing a means to water the hole, if necessary.
  • Allowing heat to escape from the hole.

It is important to keep the vent pipe clear. Therefore, hole or slit sizes should be smaller than the smallest particle size of the backfill to keep it from filling the vent pipe.

Backfill

Selection and installation of a high-quality carbonaceous backfill is critical for proper performance of all types of groundbeds. Backfills should be pumped from the bottom of the hole and the fill pipe removed.

Backfills for De Nora LIDA® tubular anodes must have the following characteristics.

  Metallurgical Coke Petroleum Calcined Coke
Resistivity Max. 50 ohm-cm Max. 50 ohm-cm
Particle Size 0.1 - 3 mm
(150-5 mesh)
0.1 - 1 mm
(150-20 mesh)
Carbon Content Min. 70% Min. 90%

 

Hole Drilling - Cleaning

In all groundbeds, regardless of anode types or bed geometry, the hole must be cleaned prior to installation of anodes, vent pipe and backfill. This prevents contamination of the backfill, which can cause high resistivity and short groundbed life.

De Nora LIDA® Tubular Anode
Manufacturing & Quality Control

LIDA® tubular anodes are available for saltwater, soil, fresh water and mud environments. These titanium activated anodes experience negligible consumption, yet can deliver electrical output higher than traditional anodes such as graphite, and high silicon/chromium cast iron. We will focus on how the LIDA® tubular strings are prepared and the quality control attendant with their manufacture.

LIDA® tubular anodes are available in 2.5 cm (1.0 inch). Cables utilized in assembling De Nora LIDA® strings may consist of the following:

  • EPR/CSPE 50: A two layered cable consisting of an ethylene-propylene inner layer and a chlorosulfonated polyethlene outer layer. The copper cross section is 50 sq. mm (AWG 1 /0). Only for salt water use.
      
  • EPR/CSPE 16: As above with a copper cross section of 16 sq. mm (AWG 6). Only for salt water use.
      
  • PVDF/Polyolefin:
    A two layered cable consisting of a radiation-crosslinked modified PVDF inner layer and a modified polyolefin outer layer. The copper conductor is AWG 6 or AWG 8.

     

String Assembly Procedure

The desired length of cable is pushed through the tubular anode units; each anode will have an anode-to cable electrical connection at the center of the tubular element and two sealing connections, one at each end of the activated titanium tube.

Initially, a section of the cable's sheathing is removed to expose the copper wire. Two silver-plated copper sleeves are fixed over the copper wire. The cable is positioned inside the titanium tube, which is uniformly crimped around the sleeves providing the superior electrical connection. The compression pressure at the crimp is rated at 50 tons.

Both ends of the tube are sealed by the same proprietary technique. No potting or mastic compounds are used in the seals. Copper, iron, or aluminum rings are interposed between the coated titanium tube and the teeth of the swaging machine in correspondence with the anode-cable connection and seals. These rings prevent the formation of micro-cracks in those areas where the titanium is subject to intense cold-working.

Quality Assurance

Quality assurance is of top priority throughout the manufacturing process. Four principal quality control measures are used on components of the De Nora LIDA® anode string and its fabrication therein:

1. Acceptability of the tubular anode
Includes certification of compliance of the titanium substrate and analysis verifications of the mixed metal oxide coating.

2. Acceptability of the power cable
The cable manufacturer must provide complete certification on all electrical and physical specifications required by De Nora for LIDA® string manufacture.

3. Electrical continuity between cable and anode
The electrical continuity between the copper conductor in the power cable and the anode is determined. The anode-cable resistance at the connection must be less than 0.001 ohm. Tracking records are maintained.

4. Hydraulic sealing between cable and anode
Hydraulic sealing between the cable insulating material and the tubular anode must be verified. This involves a pressurized helium source and leak detection verified by means of a mass spectrometer. Tracking records are maintained.

LIDA® strings are custom-assembled to customer specifications, and delivered ready to install at the jobsite. Anode centralizers can also be factory-included for further ease of installation. LIDA® tubular strings involve no field splicing and no heat shrinking. Specialty constructions are possible when required.


Ordering Information

De Nora LIDA tubular anodes are available from Farwest Corrosion Control Company. When ordering tubular anodes, please specify the following:

  • Anode Type (for example, S.T. 2.5/100).
  • Number of anodes per string.
  • Center-to-center spacing between anodes along the cable.
  • Number of tails (1 or 2).
  • Cable tail length (above the top anode).
  • Total cable length (sum of lengths of anodes, spaces and tail).
  • Current output.
  • Number of centralizers required and hole size.

Ask Farwest about De Nora’s five-year warranty!

Note:  Lida ® is a registered trademarks of De Nora in the USA, Canada and Mexico.