Steel pipe primer

Steel pipe primer Primer of metal pipes - the best protective compounds

Metal pipes are needed everywhere and always - for installing gutters, laying various types of communications, as well as for the installation of load-bearing structures and many others. The metal is strong, durable, and, if used correctly, can serve for many decades.

It has only one, but rather serious drawback - it is defenseless against corrosive effects. Most people try to protect pipes by simply painting them with an oil paint and varnish material, but this may not be enough, and the coating soon begins to peel off, fall off, and the metal surface is again defenseless against aggressive environmental influences.

For long-term operation of pipes, it is required not only to paint them, but also to carry out a complete processing with the obligatory application of a primer.

So, let's talk about priming metal pipes.

General information. Purposes for priming

The use of a primer before painting has many advantages:

  1. For processing metal products, as a rule, compositions are used with the effect of an anti-corrosion type, which are ways not only to level the surface of the pipes as much as possible, but also to ensure the uniformity of the application of the paint and varnish, and also to protect against rust formation.
  2. Significant increase in the bond strength of the paintwork to the base.
  3. Reduced construction costs, because painting steel surfaces after using a primer requires much less varnish or enamel.

  4. They can even compensate for the difference in thermal coefficient within the pipes and the surrounding atmosphere, giving an additional degree of coating strength.

Now let's talk about how to choose a primer.

The Basics of Finding the Right Primer

If you are looking to paint and buy a primer for metal, there are several critical factors to consider.


Purpose of the product

So, the composition is needed for:

  • Steel pipe primer District heating radiators - pipes are subject to temperature changes.
  • For cool water supply - the pipe surface will always be wet and cool.

  • For hot water supply - are constantly exposed to high temperature, and the surface will be dry.
  • Gas.
  • On the street (here it is worth considering the weather conditions, as well as the atmospheric impact).
  • Indoors.

The issue of quality should now be considered.

Quality and type of steel

In order to provide the required level of protection and extend the shelf life of the product, depending on its intended purpose, the following mixtures are used:

  1. Primer-insulators.They are made on the basis of typical compositions of paints and varnishes (red lead or white) with the addition of special additives, for example, an epoxy mixture. When applied, they will create a thin, durable film on the surface, which prevents the product from contacting the atmosphere. It can be perfectly used for pipes that are outside.
  2. Phosphating type as well as two-component primers.

    This heating pipe primer is a mixture of active ingredients that enhance the passivation of metal and phosphoric acid, are suitable for all types of steel pipes and have a high degree of adhesion. Often they are used before applying all paint and varnish topcoats, and also enhances their protective properties and reduces the consumption of paint and varnish.

  3. Passivation coatings alter the electrochemical properties and also inhibit the formation of rust and corrosion. The chemical properties of the compound help to protect, even if water gets under the applied paint layer. Ideal for wet pipes.

  4. Protecoor primer is a metal suspension that is dissolved in a paint and varnish base. Drying, it forms a metallic thin film, and also has high protective properties.
  5. Inhibitors - we are talking about a new generation of protective primer-enamels made on oil and water base, effectively and reliably protecting against corrosion. Suitable for pipes that are in damp conditions or outdoors.
  6. Primer-converter (for rust) based on phosphoric acid.

    The mixture will convert iron oxide (rust) to iron phosphate. The result of this chemical reaction will be an insoluble film, and can partially repair the corroded coating.

Now let's consider the temperature regime.

Content temperature

Even the temperature of the pipes will play an important role. It should also be taken into account when choosing the thermal stability of the mixture for priming and further finishing layer:

  1. Up to +60 degrees.

    As a rule, this temperature regime is quite sufficient for central heating radiators and hot water supply. Subject to each processing step, you can use any primer on a general-purpose paint and varnish base. The paint and varnish material lays on them evenly, reduces material consumption, will not fade or flake off.

  2. Up to +100 degrees. Such formulations should ideally be used for private houses, where the owners themselves will regulate the heating temperature, and the heating of the radiator can be more than +60 degrees.

    A simple primer is suitable for this, only the decorative coating should be taken with dyes resistant to fading.

  3. Primer mixes are also available that can withstand temperatures above +300 degrees. They are used only in industrial enterprises.

Please note that when buying the right solution in the store, it is extremely important to find out the consumption of priming for metal. Usually it is about 0.

1 kg per square meter.

The subtleties of the processing process

The application of a primer layer on the surface of metal pipes and heating radiators occurs in the same way as on other surfaces, but has certain features:

  • Steel pipe primer The surface must be thoroughly cleaned from a layer of old paint and rust to a shine. For this, use metal brushes. When cleaning hard-to-reach places of heating radiators, you can take metal brushes.
  • If a layer of old paint and varnish material will not come off badly, then a special softening solution should be used, which will be applied to radiators and heating pipes, and also covered with a film.

    Waiting for a little time, excess layers can be easily cleaned off with a spatula.

  • After that, the area of ​​work should be perfectly cleaned with sandpaper, gradually changing its grain size to a finer one and cleaning the metal to smoothness and shine.
  • Rinse and dry.
  • Treat dried items with white spirit or any other suitable degreaser and dry.

Priming the heating pipes will be the next step.

Depending on the size of the surface and the composition of the mixture for priming, it is applied:

  • With a brush - it will provide a more thorough treatment of uneven surfaces, but on huge flat areas (for example, long thin pipes) it will work for a long time and the expense will be large.
  • Different Roller Sizes - Using smaller rollers will greatly reduce the consumption of protection compound.
  • Spray gun.

Please note that priming takes place in several layers. The first one should be applied extremely thinly, filling in small cracks and irregularities.


After it dries, add one to three more layers if necessary. The consumption of the primer will decrease with each new layer. It is desirable to carry out the processing process on products with room temperature. Heating radiators should be turned off for a while, and this will ensure uniform drying, and also increase the quality of work and reduce the consumption of funds.

On the surface treated in this way, decorative paintwork will fit perfectly evenly, without streaks and streaks, and will also provide pipes with additional protection against temperature and moisture changes, and will greatly increase the service life.

If you take the time and correctly carry out all the processing steps before painting, then the heating systems and water supply will not need to be replaced for a long time.

Primer for pipe surfaces is a mandatory processing step, which makes it possible to consolidate the future coating, and provide protection against corrosion.The primer should be chosen depending on the purpose of the pipes, be it a gas pipeline or a radiator.