Corrosion is an electro-chemical process that results in the discoloration, pitting, and eventual erosion of a metal surface. Uncontrolled corrosion can result in equipment damage, increased power consumption, unsalable parts, and other economic stresses that can be avoided through the use of proper corrosion preventives.
A corrosion preventive provides chemical inhibition or a physical barrier to the corrosion process. They normally contain a carrier such as, solvent, oil or water. Various polar additives are used form a film on the metal surface. The product may also contain wetting agents, oxidation inhibitors, neutralizers, couplers, and additives that aid with water displacement. Factors in choosing a product include: metal type, desired film type, term of protection, application method, shipping/storage conditions, and subsequent processes and coatings.
Metal
The surface's chemistry, reactivity, and complexity are the main factors to
consider. Most metals are susceptible to some form of corrosion,
particularly if the surface has just been machined or cleaned. This must be
addressed by incorporating an inhibitor in the process fluid or applying one
immediately after the cleaning operation.
Type of Film
The type of film left by a corrosion preventive can range from a hard, dry
coating to a waxy or oily film, to an imperceptible film. The desired film
characteristics will be determined by the how the part is handled afterward
and the type of packaging or labels that are used.
Term
The term of protection is dictated not only by the initial effectiveness of the
preventive, but also by the chemical and physical stability of the film it
provides. Additives such as anti-oxidants are used for this reason.
Application
The corrosion preventive can be applied by spray, dip, swab, flow or roller
coating. The desired method will help determine the appropriate viscosity,
volatility and wetting characteristics of the fluid.
Conditions
The temperature, humidity and type of atmosphere are critical to the
required protection. Even indoor storage can place high demands on the
corrosion preventive if an adjacent process produces a corrosive
environment. Also, transfer of parts from a cold truck into a warm plant may
cause condensation that would tend to wash off a water-based film.
Next Process
Subsequent processes or coatings will often dictate the required
compatibility or cleanability of the corrosion preventive. This is especially
true if the part will be painted or plated afterward.
Process fluids offers a range of corrosion preventive products. Please review the appropriate product data sheet for specific use recommendations.
Water Dilutable | |
6200 | Synthetic - moderate protection. |
6303 | Synthetic - non borate, moderate protection. |
6400 | Soluble oil - moderate protection. |
6600-HD | Soluble oil - long term protection. |
Solvent Based | |
6510 | Water displacing. Thin waxy film with moderate protection. |
6513-D | Water displacing. Thin oily film with moderate protection. |
Oil Based | |
6000 | Water displacing. Oily film with moderate protection. |
6000-LV | Water displacing. Low viscosity oily film with moderate protection. |
Process fluids also offers an extensive range of cleaners, metalforming lubricants, machining & grinding fluids and quenching fluids. Please consult your local representative for additional information.