Category Archives: Tank Bottoms

Quick Ship Cathodic Protection for Tanks

This program applies to replacement cathodic protection systems for above ground storage tank (AST) bottoms.

cathodic protection for tanks
Tank Emergency? Contact Us About Our Quick Ship Cathodic Protection for Tanks Program

With existing ASTs, you may not always have the luxury of a planned tank bottom cathodic protection system replacement. After taking a storage tank out of service for inspection, you are often required to make an immediate decision as to the integrity of the existing floor. In some cases, this means a new floor has to be quickly planned and installed to minimize the time that the tank is out of service.

MATCOR Quick Ship Cathodic Protection for Tanks Program

MATCOR is pleased to announce our stock tank bottom anode system to meet your replacement needs with very short notice.

For your tank bottom replacement applications where a very fast delivery is required, MATCOR will now be maintaining stock of our Tank Ring Anode System.

  • Up to 200 ft diameter SPL-FBR tank ring anodes
  • Pre-assembled and ready to ship from our Chalfont PA facility
  • Two day turnaround
  • Set up in concentric rings with five foot spacing
  • Requires a minimum of just 6 inches of sand cover from the new tank bottom
  • Designed for 25 mA/ft output which is generally sufficient for 50+ year anode life based on a nominal current density of 2 ma/ft2 of surface area.

For more information please contact your MATCOR sales representative or contact us at the link below.


Have questions or need a quote for a replacement tank bottom cathodic protection system? Contact us at the link below.

CONTACT A CORROSION EXPERT

Tank Farm Design Recommendations for Corrosion Prevention

Tank Farm Design RecommendationsWhether designing a few above ground storage tanks or performing tank farm design for an entire facility, proper consideration should be given to the adverse impact of corrosion that can occur on the tank bottoms. When addressing the issue of tank bottom corrosion, consider the environment, the tank size and design, and the type of tank foundation to be employed. There are definite advantages in certain materials based on the size and requirements of an above ground storage tank (AST) foundation. By carefully assessing the tank farm surroundings and long-term requirements, costly and potentially dangerous corrosion related tank failures can be avoided. Whether you are relying on a reputable company in the industry or taking on your own front-end engineering and design, there are across-the-board tank farm design recommendations to consider when it comes to corrosion prevention:

In terms of corrosion prevention for under ground storage tank (AST) foundations, is cathodic protection (CP) effective?

For tanks erected on compacted soil or sand foundations, with or without a concrete ring wall, cathodic protection is considered a “good engineering practice” and has been proven as an effective means of addressing tank bottom corrosion concerns. When you compare various methods of corrosion prevention for above ground storage tank bottoms, CP is shown to prevail over asphalt or concrete unless your project involves smaller diameter tanks. The corrosion failure rate is greater for tanks built on asphalt or concrete compared to tanks where a concentric ring cathodic protection system is installed.

In terms of corrosion, when is asphalt or oil/sand acceptable for above ground storage tank (AST) foundations?

Asphalt foundations are not common in the United States, as the mechanical integrity of asphalt can be an issue depending on the AST environment. As well, the use of oil/sand layer designs has been phased out by most tank owners in the United States due to the adverse impact that these oil/sand layers have on tank bottom cathodic protection systems. While historically prevalent in the Middle East and Asia, most larger national oil companies have abandoned this approach because it causes shielding of cathodic protection (CP) current, allowing corrosion to occur. Kuwait Oil, Aramco, and others now prefer clean sand combined with CP as the base material of choice. This is standard in the United States and has been for several decades.

What is a Concentric Ring Cathodic Protection System for above ground storage tanks (AST)?  

A. Designed for long-term storage, an AST cathodic protection ring system offers a factory-assembled design whereby the anode rings are ready to install with cable leads that extend past ring wall penetration. Concentric rings sizes are made to order, requiring no onsite welding, cutting, or splicing. The anode locations are marked, rings are laid out, and cabling is placed using a proven labeling system for future monitoring. A mixed metal oxide (MMO) anode is centered among a low-oxygen-generating coke backfill to eliminate depolarization.

Learn about MATCOR’s complete AST cathodic protection design services.

Are there some cases where concrete foundations are advantageous for tank farm corrosion prevention?

During installation of above-ground storage tanks, there are some advantages to concrete foundations for tanks when it comes to corrosion—the high pH of the concrete acts to passivate the steel, unless you have an above ground storage tank (AST) liner pad or something that is between the concrete and the tank bottom. If you can effectively seal the chime from the ingress of water and oxygen, the corrosion rates are generally quite small. Unfortunately concrete foundations for larger diameter tanks are not typically practical and can be quite expensive to properly install. Concrete foundations with appropriate AST liners are best for smaller diameter tanks.

In tank farm design for corrosion prevention, what are the best recommendations for above ground storage tank (AST) liners?

Plastic secondary containment liners are largely phased out in the United States and have been replaced by geotextile membranes that serve the same secondary containment purpose as plastic—they are conductive to allow cathodic protection (CP). The general standard in the United States is to have a CP system directly under the tank in order to minimize stray current or current losses due to earthing systems around the tank. Since the tank bottom is a large bare structure and the anodes are closely coupled to the tank bottom, there is usually very little current drain to other structures; the system if properly designed can accommodate modest current drain. While a plastic liner provides isolation from other nearby structures, when a problem arises with the CP system or if the CP system reaches the end of its projected service life, there is no way to install a new CP system without replacing the tank bottom.

Tank farm corrosion prevention is more manageable now than ever before. The MATCOR Concentric Ring Cathodic Protection System™ is just one of many excellent options for protecting your above ground storage tank (AST) from damaging corrosion.


For assistance with tank farm design, our Concentric Ring AST Cathodic Protection System™, project management or installation, please CONTACT US.

Learn more about Tank Cathodic Protection


MATCOR Corrosion Experts Launch New App for Tank Cathodic Protection System Design

Design a Detailed Tank Ring Anode System for an Above Ground Storage Tank in Seconds with MATCOR’s Web Application.

Chalfont, PA – August 28, 2014, MATCOR, Inc., the trusted full-service provider of proprietary cathodic protection products, systems and corrosion engineering solutions, launched a valuable, timesaving web application that enables corrosion professionals to design a cathodic protection system for their above ground storage tanks (ASTs) in seconds.
Isaac Renfro, NACE Workforce Development Program graduate and MATCOR Technician
“This web-based app makes it easy for our customers to design tank cathodic protection systems and enables rapid turnaround for a quote,” says Douglas Fastuca, President of MATCOR. “An ease-of-use and quick response philosophy is consistent with MATCOR’s Tank Ring Anode System, which is very easy and safe to install within a few hours. With this productivity tool MATCOR continues its tradition of innovation and enabling creative cathodic protection solutions.”

The MATCOR Tank Ring Anode System App is available at matcor.com/tankring. The user enters specifications for their above ground storage tank and installation environment, and the app delivers detailed tank ring anode cathodic protection system design specifications. MATCOR will then quickly quote and manufacture an accurate, reliable impressed current cathodic protection system, which utilizes patented Kynex® waterproof connection technology.
The factory-assembled MATCOR Tank Ring Anode System is fast and easy to install with no field anode assembly required. A small crew can install most systems in under two hours with no welding, hot permit, splicing of anode sections or special backfill required. MATCOR offers Tank Ring Anode Systems for new and retrofit tanks.


Learn more about AST Cathodic Protection


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