Xi'an KIG Technology Co., Ltd

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MMO Anodes vs. High-Silicon Cast Iron Anodes

As a professional manufacturer of cathodic protection materials, we supply both Mixed Metal Oxide (MMO) anodes and High-Silicon Cast Iron (HSCI) anodes. Both are used in impressed current systems to protect pipelines, tanks, and other buried or submerged assets, but their performance differs with soil conditions and design requirements.

Product Overview

· MMO Anodes – Titanium substrate with a stable Ir/Ru or Ru/Ta coating. Very low consumption, high current density (up to 100 A/m²), and service life of 25–50 years. Lightweight and available as tubular, ribbon, or mesh types.

· HSCI Anodes – Cast iron with 14–15 % silicon (optional chromium). Robust and cost-effective, with typical current density of 10–20 A/m² and service life of 20–30 years.

KIG MMO anode is in production

Soil Resistivity Guidance

· MMO: Best for high-resistivity soils (>50 Ω·cm), deep-well systems, and sites where long life and high output are critical.

· HSCI: Performs well in low- to medium-resistivity soils (<50 Ω·cm) such as moist clay, loam, or seawater environments where current demand is moderate.

· But a better choice depends on the **full set of soil and environment parameters**: resistivity, moisture, chemistry, temperature, desired life, maintenance, how much driving potential you have, etc.

Detailed Comparison

Feature	MMO Anodes	High-Silicon Cast Iron (HSCI) Anodes
Material Composition	Titanium substrate with IrO₂/RuO₂ coating	Cast iron with 14–15% silicon, optional Cr
Current Density	Up to 100+ A/m²	Typically 10–20 A/m²
Consumption Rate	Virtually zero (titanium remains intact)	~0.2–0.5 kg/A·yr depending on conditions
Service Life	25–50+ years	20–30 years (depending on soil resistivity)
Installation Flexibility	Multiple forms: tubular, ribbon, mesh, wire	Primarily tubular or solid rods
Weight	Lightweight	Heavy, requires robust handling equipment
Cost	Higher initial investment	More economical upfront
Maintenance	Minimal	Moderate, periodic monitoring recommended

Choosing the Right Anode for Your Project

The selection between MMO and HSCI anodes depends on project-specific factors such as soil resistivity, operating current density, design life, and budget.

MMO anodes are ideal for high-current or long-life applications where maintenance access is limited. They provide exceptional efficiency and stability, making them the preferred choice for critical infrastructure requiring minimal long-term risk.
HSCI anodes remain a reliable and cost-effective option for environments with moderate current requirements and where upfront cost control is a key consideration.

One-Stop Solution

We provide complete cathodic protection packages—MMO and HSCI anodes, transformer rectifiers, cables, and sealing materials—supported by NACE-certified engineers for system design. Whether you need long-life MMO for high-resistivity soils or cost-effective HSCI for low-resistivity sites, we deliver the right solution to protect your assets.