Grid layout
Ribbon conductors and cross-connections can form a distributed network across the tank footprint.
Tank Bottom ICCP · Grid & Linear Systems
MMO Anode Systems for Tank Bottom Cathodic Protection
Project-configured MMO ribbon, mesh-ribbon, wire and linear anode assemblies for external corrosion protection beneath aboveground storage tanks.
Anode layout, spacing and current output depend on tank diameter, foundation, liner, coating condition and CP calculation. Do not select an under-tank grid from a generic spacing rule.
Grid & ring layouts
New or replacement
Foundation review
Monitoring-ready
Application Basis
How Tank Bottom ICCP Protection Works
An under-tank ICCP system distributes protective current across the external surface of the steel bottom. MMO ribbon, mesh-ribbon, wire or linear anodes are installed in the foundation or interstitial space according to the approved geometry, while reference electrodes and monitoring points support commissioning and long-term control.
The layout must account for foundation resistivity, sand pad, liner or membrane, tank-bottom coating, replacement-bottom geometry, electrical continuity and construction sequence. HELE supplies the agreed anode components and assemblies; the tank CP designer confirms zoning, current demand and monitoring strategy.
Selection Framework
Grid Anodes vs Concentric Ring Linear Anodes
Select the distribution pattern from tank geometry, foundation construction, installation timing and current-distribution model.
Mesh-ribbon layout
Expanded or mesh-ribbon elements can provide a low-profile distributed arrangement with specified connection details.
Concentric rings
Linear or wire anodes can be routed in rings to suit a circular tank and project-defined zoning.
Double-bottom retrofit
The interstitial geometry, spacer arrangement, penetrations and monitoring access control constructability.
Anode Options
MMO Anode Forms for Under-Tank Layouts
The preferred form must be tied to the installation drawing, crossing or splice design, cable routing and foundation method.
MMO Ribbon Anode
Best considered when: a low-profile grid or ring element is specified for controlled routing beneath the tank.
Confirm: ribbon width/thickness, coating/loading, crossing connections, leaders and termination.
MMO Mesh Ribbon
Best considered when: a distributed mesh element suits the approved foundation or interstitial layout.
Confirm: mesh geometry, connection tabs, layout panels, joints and placement method.
MMO Wire Anode
Best considered when: a flexible anode route is needed for rings, perimeter runs or localized zones.
Confirm: wire diameter, active length, insulation transitions, joints and termination.
MMO Linear Anode
Best considered when: a cable-type anode assembly is designed for concentric or distributed installation.
Confirm: attenuation, active length, cable construction, seals, joints and reel handling.
Configuration Logic
New Tank, Replacement Bottom and Double-Bottom Layouts
A new-build layout can be coordinated with the foundation before the bottom plate is installed. A replacement or double-bottom project may constrain anode height, routing, penetrations and test access. The issue-for-construction package should show each anode run, junction, reference electrode, monitoring lead and protected work sequence.
Design Control
Tank diameter alone is not enough to determine layout or quantity. Foundation layers, liner, coating condition, current distribution and monitoring locations must also be reviewed.
Engineering Matrix
Tank Bottom Anode System Inputs
The following items define the supply basis. Final values are confirmed by the cathodic-protection designer and project review.
| Decision | Why it matters | Evidence to provide |
|---|---|---|
| Tank geometry | Defines the protected footprint and distribution pattern. | Tank diameter, bottom arrangement, annular plates and layout drawing. |
| Foundation | Controls electrolyte path and installation method. | Sand pad, concrete, membrane/liner, resistivity and layer thicknesses. |
| Project type | New, replacement and double-bottom tanks have different access. | Construction sequence, available clearance and penetration details. |
| Current demand | Drives zones, anode length and power inputs. | CP calculation, coating basis, design current and design life. |
| Monitoring | Supports commissioning and long-term control. | Reference electrode type/location, test leads and data collection plan. |
| Connections | Field joints and continuity affect the distributed network. | Connection detail, welding method, cable schedule and inspection plan. |
Project Inputs
Data Required Before Manufacture
- Tank diameter, bottom arrangement and construction drawings
- New-build, replacement-bottom or double-bottom project type
- Foundation, sand pad, membrane/liner and resistivity data
- Bottom coating condition, design current and target design life
- Required grid, ring or mesh layout and zoning philosophy
- Cable, connections, reference electrodes, documents and schedule
Installation & QA
Interfaces That Must Be Controlled
- Verify anode routes, crossings, spacing and reference locations against drawings
- Protect ribbon, mesh, wire, joints and lead cables during foundation work
- Inspect field welding or connection method and electrical continuity
- Record pre-cover checks, photos, coordinates and test results
- Prevent damage during sand placement, compaction and bottom construction
Supply Boundary
Anode Supply vs Complete CP System Responsibility
Define responsibilities in the purchase specification. HELE can configure and manufacture agreed anode components or assemblies; complete system engineering is not automatically included.
HELE supply can include
- MMO ribbon, mesh-ribbon, wire or linear anode elements
- Factory leads, terminations and specified connection hardware
- Project-specific layout panels or assemblies where agreed
- Drawings, inspection records, packing and traceability documents
Confirm separately in the contract
- Final tank CP design, current calculation and anode spacing
- Foundation design, civil work and field installation
- Rectifier, reference electrodes and monitoring unless specified
- Commissioning and acceptance testing unless contracted
Related Pages
Continue the ICCP Selection Path
Installation Configurations
Compare under-tank layouts with other ICCP arrangements.
MMO Ribbon Anodes
Low-profile ribbon elements for distributed layouts.
MMO Mesh Ribbon
Mesh-ribbon options for under-tank grid systems.
MMO Wire Anodes
Flexible wire elements for ring and localized layouts.
MMO Linear Anodes
Continuous anode systems for concentric configurations.
ICCP Anodes Overview
Review the complete ICCP anode product family.
FAQ
Tank Bottom ICCP Anode Questions
Which MMO anode layout is best for a tank bottom?
The choice between grid, mesh-ribbon and concentric linear arrangements depends on tank geometry, foundation, liner, project type, current-distribution model, construction sequence and monitoring plan.
Can a tank-bottom anode system be installed during a retrofit?
Yes, but replacement-bottom and double-bottom projects have different clearances, routing and construction interfaces. The issued design must match the actual interstitial arrangement.
How is under-tank anode spacing determined?
Spacing is established by the responsible CP designer using the tank dimensions, foundation and liner configuration, coating condition, current demand and current-distribution requirements.
What should be checked before the tank bottom covers the anodes?
Verify routes, spacing, connections, continuity, lead identification, reference electrodes, cable protection and as-built records, then document the approved pre-cover inspection.
Does HELE supply reference electrodes and the rectifier?
They can be reviewed as separate project scope. The standard page scope is the MMO anode component or assembly, and any added monitoring or power equipment must be listed in the RFQ.
What data should be sent for a tank-bottom anode quotation?
Send the tank and foundation drawings, project type, CP design current, design life, proposed layout, anode specification, cable and connection details, monitoring requirements, quantity, destination and schedule.
Technical RFQ
Get Your Tank Bottom ICCP Anode Recommendation
Tell us your tank diameter, foundation design, soil or sand resistivity, current demand, design life target, preferred anode layout, cable routing, reference electrode requirements, and documentation needs. Hele Titanium will help review suitable MMO anode forms and tank bottom ICCP configurations for your project.
- MMO Ribbon, Mesh Ribbon, Wire and Linear Anode Support
- Under-Tank Current Distribution and Spacing Review
- Cable Connection, Labels and Documentation Support
- Factory-Direct MMO Anode Manufacturing and Export Packing