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Cortec M-531

by Cortec
Original price $858.57 - Original price $8,744.68
Original price
$858.57 - $8,744.68
Current price $858.57
Choose a Size
Low stock
Ships in 1 to 2 weeks

M-531 is an oil-based package of corrosion inhibitors for petroleum and synthetic lubricants. M-531 provides outstanding non-staining properties with excellent demulsibility and filterability.

M-531 is very effective for napthenic, iso-paraffinic, PAO, etc. based lubricants.


  • Excellent rust inhibitor
  • Excellent non-staining properties
  • Excellent filterability
  • Can be used in hydraulic applications
  • When added at recommended concentration to hydraulic fluids, does not affect emulsification, pour point, or viscosity at low temperatures
  • Compatible with most mineral and synthetic oils
  • Suitable for both operating and intermittent use conditions
  • Resists gelling when contaminated with water

Typical Application
M-531 can be used in a wide variety of industrial lubricant applications where excellent rust protection, filterability, and water resistance are required. In rust preventive applications it is particularly useful for coiled steel or stacked parts due to its outstanding non-staining properties.

M-531 is highly recommended for use in hydraulic fluids. M-531 is also ideally suited for formulating paper machine oils and circulating oils where good filterability, anticorrosion, thermal stability, and demulsification properties are required.

Soluble in petroleum and synthetic lubricant base stocks and most common solvents. Insoluble in water. However, it is recommended to verify the solubility in the base oils used and the compatibility with other additives.

Metals Protected:

  • Carbon steel
  • Copper
  • Solder
  • Stainless steel
  • Cadmium
  • Tin
  • Galvanized steel
  • Magnesium
  • Lead
  • Aluminum
  • Silver
  • Bronze
  • Brass
  • Zinc

Typical Properties
Appearance: Brown viscous liquid
Non-volatile Content: 91-97%
Density: 7.6-8.0 lb/gal (0.91-0.96 kg/l)

When added at concentration level 2-5% by weight to Hydraulic or Gear oil

ASTM D 1748
Corrosion Protection in Humidity Cabinet
5+ Days
ASTM D 1401
Water Separability of Petroleum and
Synthetic Fluids
• Does not cause emulsification
• Does not affect oil water separability

Packaging and Storage
Available in 5 gallon plastic pails (Cortec Product # 12100022) or 55 gallon metal drums (Cortec Product # 12100023). 5 gallon drum weighs 50 pounds and ships under our standard shipping rates. The 55 gallon drum must be shipped by truck. We will provide you with a freight quote before we ship this product. Store in a cool, less than 115°F (46°C), dry place away from any direct source of heat and moisture. M-531 should be sealed before storage. The shelf life is up to 24 months.

Quantity Discounts Available for Large Orders. Please call for more information.

Need more information?

Call a Product Specialist

Monday through Friday, 8 a.m. - 4:30 p.m.
Phone U.S.: 1-877-256-9301
Fax: 608-203-1112

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Emails are answered Monday through Friday