History of ENC Coatings
Electroless Nickel Coating (ENC) has over 50 years of development history, all starting in the lab. To bring such a technology into industrial applications, early researchers/developers struggled with basic reaction principles, formulas vs. plating rates/qualities, long-term stable operation, stable quality thickness build up, standard operation procedures, hardening, bonding, etc. Successful applications of ENC started to show up in the late 1990’s when companies were able to generate good quality products in an economical manner. This was also in conjunction with much stricter bans placed on various electroplating operations due to environmental concerns.
For very strong corrosion resistance needs, organic and ceramic products have shown excellent results. However, their shortage on strength and expensive shaping costs have limited them from most applications. ENC – an amorphous mixture of nickel and phosphorous, provides both metal’s strength and excellent corrosion resistance (close to organic material). The extra advantage of ENC is that the coating can be hardened at a low temperature without deformation, which renders it self-lubricating. These advantages of ENC cannot be offered by electroplating (such as hard chrome) and immersion coating (such as zinc coating) products.
What exactly is Electroless Nickel Coating (ENC)?
ENC is a nickel-phosphorous alloy deposited by a chemical reaction from hypophosphite on a catalytic substrate, without the application of an electrical current. The coating thickness, anywhere from 0.0005 inch to 0.004 inch, is controlled by the length of time the metal substrate is left in the chemical bath solution. This autocatalytic chemical reaction deposits a controlled and uniform thickness even on complex part geometry and eliminates the need to mask off areas and grind weld seams. Another significant advantage of ENC is that clean, economical material such a new carbon steel does not need sandblasting prior to coating, nor being machined after coating. This reduces time and cost, as well as avoiding potential damage on delicate machined parts. ENC prevents corrosion on carbon steel, aluminium, brass, copper and high alloys such as Inconel.
Click HERE to view a paper created by Cenovus, in partnership with Harber Coatings, on the effectiveness of ENC coatings.
Current Developments of ENC Focus on the Following Aspects:
Better corrosion resistance/wear resistance/bonding study of traditional ENC
Industrialized multi-element platings (Ni-P-B, Ni-P-Co, etc.)
Composite ENC (Ni/P/PFA, Ni/P/SiC, etc.)
Aged ENC solution regeneration
InnoGUARD™ is the “new generation” in ENC coatings
It all begins with an idea.
The coating is stronger than previous ENC products … up to 900 Vickers Hardness (greater than 68 Rc).
The adhesion (bonding) is much better than previous and competitor ENC products – it does not flake or peel when mechanically impacted or when exposed to abrasive or highly corrosive environments such as steam, H2S, CO2, oxygen, brine water and high chlorides. Most of our competitors use off-the-shelf commercial solutions and these ENC formulas are not scratch-resistant and often experience failure such as peeling or flaking. We offer a LIFETIME NO FLAKING OR PEELING GUARANTEE!
Our coating process is eco-friendly. It does not contain toxic additives like previous generations of ENC, or as other coatings such as epoxy, polymers and chrome. Our process does not contaminate the environment or give off toxic fumes.
If corrosion eventually occurs due to excessive wrenching or extreme abrasive factors, the corrosion never penetrates between the InnoGUARD™ coating and the substrate. Any small amount of corrosion remains localized to the damaged area only and the rest of the coating does not peel or flake off.
Typical Oil and Gas Applications
It all begins with an idea.
Downhole tools, multi-stage frac tools, packers, pup joints, completion tools, wireline tools, slotted pipes, BOP’s, spools, ANSI & API valves, pumps, tubing, rods, pistons, cylinders, hangars, flanges, pump plungers & liners, pump housings, impellers/shafts, pressure vessels, strainers, pipes and fittings, fracing valve elements, sand screens, reciprocating pump barrels, rotors, gear boxes, bearings, etc.
20 Key Benefits of InnoGUARD™
It all begins with an idea.
Cost-effective way to extend the working life of your raw tools & parts by 20X or greater.
Superior bonding ensures it does not peel or flake when mechanically impacted. It does not require a secondary polymer dip to prevent peeling or flaking like other ENC coatings.
Provides supreme resistance to highly corrosive environments such as steam, H2S, CO2, high calories, oxygen, and brine water.
Can withstand temperatures up to 880 degrees Celsius.
Reduces surface friction by 2/3 and is self-lubricating.
Can withstand high torqueing and compressive stress.
Consistent coating uniformity and thickness regardless of the part/tool geometry and cost efficient way to salvage mis-machined part and tools.
Available in varying thicknesses from 0.0005 inch to 0.004 inch, depending on application needs and specifications.
Coats the interior and exterior of the part or tool for the same cost.
Comparable in cost to epoxy or polymer coatings, with much better performance.
Effectively coats sharp edges, deep recesses, seams, threads and blind holes without impacting function.
Due to being a metallic coating, it has the same thermal co-efficient as the substrate and when the metal contracts or expands, no micro-cracking occurs as it does with epoxy or polymers.
Clean metals, such as new carbon steel, do not need to be sand-blasted prior to coating, therefore reducing costs and ensuring the substrate isn’t damaged.
Provides a more durable for surface on surface friction abrasion than hard chrome, especially in lubricated conditions.
“Electroless” means that no electrodes need to be attached for the coating process, therefore no areas are excluded in coating.
If the coating is damaged by excessive wrenching, corrosion remains localized to the damaged spot; corrosion will not extend between the coating and the substrate.
Maintains an identical surface profile prior to coating, ensuring the same smoothness is achieved as the substrate material used.
Metals that can be coated include carbon steel, stainless steel, aluminum, titanium, brass, copper, zinc and alloys (such as Inconel).
No machining required after coating and no grinding of weld seams prior to coating saves on time and cost.
