Conventional Anti-Corrosive Paints
Anti-corrosive paints cracked, minute cracks form, often barely visible to the naked eye, but still sufficiently large to let oxygen and moisture through. This is a sure foundation for rust.
This illustration above shows how the rust expands under the layer of paint, damaging more metal. This is often not visible on the surface until the damage is so large that a complete re-paint is the only alternative.
Due to their rheological properties, conventional paints provide considerably thinner film on sharp edges and in corners.
This fact, combined with uneven erosion of the paint layer, means that corrosion can appear relatively quickly in corners and on the edges of a steel structure.
Dinitrol Waxcoating System
The Dinitrol Waxcoating System’s waxy film does not crack. This eliminates the risk of under-corrosion. Even if a scratch should damage the film, the corrosion will not go further as the actual damage. The rust can’t spread as the wax film adheres very strongly to the metal surface. Adhesion is greater than cohesion.
Dinitrol Waxcoating provides a film of uniform thickness over the entire surface, including edges and corners. This, combined with the uniform erosion of the wax, results in proper corrosion protection even on sharp edges.
The DINITROL WAXCOATING SYSTEM is the new, long-lasting way to protect large and small steel structures such as cranes, bridges, pillars, roofs and containers against rust.
DINITROL WAXCOATING PRIMER
is a thixotropic, high-penetrating rustproofing fluid which forms a protective film both on flat surfaces and in cavities. This fluid is mainly composed of synthetic waxes, oil, rust inhibitors and solvents. The primer provides a transparent waxy, water-repellent protective film with excellent protection against corrosion on zinc and aluminium.
DINITROL WAXCOATING
is a thixotropic rust-protection product composed of waxes, rust inhibitors and various pigments. It provides a non-tacky protective film .
As it is so thixotropic, DINITROL WAXCOATING does not run when applied. One coat provides a film of sufficient thickness.
DINITROL WAXCOATING is intended to be used as corrosion protection on iron, steel, zinc and aluminium constructions such as bridges, beams, road barriers, roofs, ventilation ducts, tanks and containers.
It is applied as stage 2 of the anti-corrosion system and seals in the penetrating product used in stage 1. It provides an elastic, drying non-tacky wax film.
DINITROL WAXCOATING PRIMER’s ability to penetrate deep into joints and crevices simplifies preparation prior to anti-corrosion treatment, making the process even more economical. The primer’s water repellent properties mean that anti-corrosion work is less dependent upon the weather. The DINITROL WAXCOATING film is easily and quickly removed. The DINITROL WAXCOATING SYSTEM is particularly suitable for the following three protection situations:
- For the repair and renewal of existing corrosion protection when rustproofing paints have cracked for example.
- As a protective layer on top of intact corrosion protection paint. This eliminates costly future corrosion repairs as the DINITROL WAXCOATING SYSTEM prevents paint cracking.
- As the only corrosion protection on objects not exposed to continual mechanical wear.
Bridges and Their Sensitive Bolt Joints or Rust Protection of Jointed Steel Structures
The problem. The load-carrying steel structure in a bridge is continually exposed to large temperature stresses and vibrations. Steel bridges, normally coated with anti-corrosive paint are joined together with thousands of bolts. After a while all paint round these vital bolts comes away and cracks, opening up the way for rust. This situation can arise after just a year or two.
Action that solved the problem. The anti-corrosion operator had first to remove the remains of some 20 coats of paint which had been applied over the years. In addition, all loose rust and flakes were removed from the area round the bolts. After cleaning, DINITROL WAXCOATING PRIMER was sprayed on as it has the ability to penetrate In behind the bolt and effectively prevent further corrosion. The anti-corrosion treatment of the bridge was completed with the application of the thicker DINITROL WAXCOATING.
Vibrations and temperature stresses will not affect the waxcoating products.
Corroding Brewery Pipes or Surfaces Constantly Exposed to Condensation and Temperature Variations
The problem. Large temperature differences occur in breweries when refrigeration plant is used. This causes condensation and ice to form on pipes, which results in cracks in the anti-corrosion paint. Rust is then unavoidable. Attempts to repair this damage by applying new coats of paint are both time-consuming and rarely successful.
Action that solved the problem. Loose paint And rust flakes were removed. High-penetrating DINITROL WAXCOATING PRIMER was applied to prevent old rust from spreading and new from starting. This was followed by the application of DINITROL WAXCOATING, a thick layer of sealing film. As preparation work is faster and simpler, the waxcoating method is more effective than anti-rust paint. The long-lasting anti-corrosion protection provided in a case like this is far superior to ordinary paint.
Transformers and Their Sharp Edges, or Rust Protection of Edges and Corners
The problem. This type of transformer is usually sited outdoors without protection. Due to the design, the coolers have a large number of sharp edges. Because of the surface tension in conventional anti-corrosion paint, the paint film on these sharp edges is almost non-existent. In this situation, paint does not provide anti-corrosion protection.
Action that solved the problem. By coating the whole of the transformer’s cooler unit with DINITROL WAXCOATING, an unbroken and even film layer was obtained both on flat surfaces and round sharp edges. The waxcoating system is preferable both when touching up surfaces earlier treated with anti¬corrosion paint, and when treating new transformers for the first time.
The Invisible Rust in the Wind Power Rotor or How to Manage Rust in Closed Cavities
The problem. Growian is an experimental wind Generator in West Germany. And it’s impressive. It’s 150 metres high and has a propeller diameter of 100 metres.
This enormous propeller is prone to corrosion, Mostly on the inside, but on the outside as well. Due to the stresses the propeller material is exposed to when in operation, any weakening of strength, caused by corrosion for example, would have serious consequences for the entire plant. This risk is quite considerable. The propeller itself can be looked upon as a badly ventilated closed space, a classical breeding-ground for heavy rust.
When the power station was being built, it was already decided that effective corrosion protection was essential.
Action that solved the problem. The inside of the propeller was coated with a special kind of DINITROL WAXCOATING. Due to the speed of rotation, the waxcoating film is exposed to very high centrifugal force which placed special requirements on adhesion properties. Other, non-rotating parts of the housing, such as screws, were treated with conventional DINITROL WAXCOATING.
DINITROL WAXCOATING was also selected for internal corrosion protection of the propeller due to the difficulty of economically applying paint and achieving proper penetration of all joints and seams.
Internal and External Maintenance of Pillars and Tubes
The problem.Corrosion was discovered round the bolts in this 40 metre high pylon. The pylon as a whole was protected with anti-corrosion paint, but in the course of time the paint had cracked and cracked around the bolts and left these important parts completely un-protected. The paint had been worn away by vibrations and movement of the pylon. Another coat of anti-corrosive paint would not have solved the problem as paint does not penetrate sufficiently.
Action that solved the problem. The area around the bolts was first carefully cleaned, all loose paint and rust flakes were removed. Penetrating DINITROL WAXCOATING PRIMER was then sprayed on to provide effective protection in all the joints and seams which were difficult to reach. This treatment was then sealed in with a film of thicker DINITROL WAXCOATING which is unaffected by vibrations or temperature differences.
Not even galvanised surfaces offer full protection against rust in today’s tough environment. A hollow zinc-coated steel pole for street-lighting, for example, is liable to rust primarily because of air pollution and damp. An excellent way to eliminate this rust formation is to treat with DINITROL WAXCOATING PRIMER internally and with DINITROL WAXCOATING externally.
Corrosion Protection of Structures in an Aggressive Environment
The problem. Chemical process plants and refineries are extremely exposed to corrosion. Corrosive vapours and fluids, damp and conden¬sation, and rapid changes in temperature are adverse effects which the process industries are both exposed to and also generate themselves. There are thousands of miles of pipes in a refinery of any size. These pipes are often treated with anti-corrosive paint which is damaged and des¬troyed in many places by the corrosive environ¬ment. Pipe flanges are a further problem as they have crevices and joints which are difficult to get at. After a while these flanges become so rusty that they have to be cut off with a torch to get the pipes apart.
Action that solved the problem. Loose rust and paint flakes were first removed from both pipes and flanges. High penetrating DINITROL WAXCOATING PRIMER was then applied and sealed in with a thick layer of DINITROL WAXCOATING. By repairing the corrosion protection with DINITROL WAXCOATING SYSTEM, instead of simply repeating the anti-rust painting, the result was both faster and simpler preparation besides better, longer-lasting corrosion protection. Flanges should, however, always be treated with DINITROL WAXCOATING at the time of installation to eliminate rusting together.
