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Cortec M-645

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Product Description

M-645 is a float coat used to inhibit corrosion in vessels containing saltwater or brine. It floats on the surface of the water, forming a self-healing protective film on adjacent metals. The film displaces water containing chlorides from the surface of the vessel. As the water is raised or lowered, M-645 coats every square inch of the vessel’s interior— including ring stiffeners, girders, piping, and side shells—with a sufficient amount of product to protect against corrosion.

M-645 is ideal for ballast tanks that are frequently emptied and refilled. Because M-645 floats on the surface of the water, the non-aqueous formula does not contaminate ballast water, allowing for normal discharge procedures. It is also an effective corrosion inhibitor for hydrotesting large aboveground storage tanks (ASTs).

UFI: SWA0-409N-600K-P6VE

Packaging & Storage

M-645 is available in 5-gallon (19 L) pails, 55-gallon (208 L) metal drums, liquid totes, and bulk.

To ensure best product performance, store in original packaging, indoors, and out of direct sunlight at 40-100 °F (4-38 °C).

Shelf life: 2 years

Features

  • Non-hazardous  
  • Non-flammable  
  • Self-reapplying  
  • Not water-miscible

Benefits

  • Provides corrosion protection for a broad range of saltwater/brine applications  
  • Extends ballast tank life, minimizing costs for dry docking repairs  
  • Does not interfere with ballast water discharge  
  • Effective for multiple tank refills

Application

Due to the uniqueness and complexity of float coat applications, please contact Cortec® for recommendations on your specific use. Typical applications include

  • Hydrostatic testing of pipelines, vessels, and ASTs 
  • Seawater ballasting of ships, buoys, and oil rigs

Metals Protected

  • Carbon Steel 
  • Steel Alloys

Typical Properties

AppearanceClear brown to amber liquid
Density7.5-7.7 lb/gal (0.90-0.92 kg/L)
Flash Point201 °F (94 °C)
Viscosity33.33 cSt at 104 °F (40 °C)

Dosing & Coverage Rate

M-645 is dosed based on the surface area and geometry of the treated space. The amount of M-645 required is based on the cross-sectional area and tank surface area:

  • 13 gallons per 100 square feet (55 L/ 10 m²) of cross-sectional area (7.7 ft²/gallon [0.19 m²/L])  
  • 0.12 gallons per 100 square feet (0.5 L/ 10 m²) of tank surface area (830 ft²/gallon [20.37 m²/L])