In the chemical industry, the service lives of equipment are a key efficiency issue. Thermally sprayed coatings can be found in a variety of types and methods. Basically, two different areas of application can be assumed. Either they are components that are made of a cheaper, non-corrosion-resistant base material and are to be protected with a thermal corrosion-resistant spray coating at the point where the corrosive attack takes place. Or they are components that are made of a corrosion-resistant, but softer base material and have to fend off the additional attack from wear by means of a thermally sprayed coating.
The high demands on surfaces in chemical processes put many materials to the test. rhv-Technik brings many years of experience in this case. Our solutions are innovative and build on a large number of successful projects relating to chemical processes.
In the sealing sector, we have had good experiences with thermal Hastelloy coatings to protect against corrosion, for example.
There are also solutions for aggressive substances. Pumps or rotors can convey different media, such as aggressive sewage sludge, concrete, acids or bases, medicines or food. In addition to the corrosion attack, there is often also an abrasive load. Molten and thus non-porous, dense nickel-based spray coatings offer ideal protection against both attacks and thus significantly improve the service life. Alternatively, a chrome carbide coating can also be used, which at the same time protects the stator.
Chemical processes are among the most demanding in the field of industrial applications. It is important to withstand aggressive media (gases, acids, alkalis, etc.) and to reliably cope with mechanical loads. Corrosive and abrasive stresses often interact with the surfaces. In addition, there are changing aggregate states of the media from liquid to pulp through to a powdery state.
The durability and thus the service life of the coated component are increased many times over by a thermal coating, depending on the medium and the application. Should the tribological system also experience stress due to exceptionally high pressures, a thermal spray coating can be used to optimise the material ratio of the surface to the maximum.
Our individually tailored thermal coatings based on Hastelloy, chrome carbide, chromium oxide or aluminium oxide-titanium dioxide ceramics enable lower wear, longer service lives and improved cost-effectiveness.
Thermally sprayed materials can withstand temperatures of up to 900 °C or pressures of up to 300 bar, regardless of the physical state of the medium. For gases, however, either molten and thus largely gas-tight coatings are recommended or a chromium oxide coating specially developed by us, which is almost pore-free and has a hardness of about 1300 HV.
In addition to the coating of new parts, where one can speak of a forward-looking design, the repair also plays an important role. In particular, when inspections of sealing or pump systems are pending, the time factor is crucial. Thanks to thermal spraying, a quick reconditioning, e.g. of pump sealing seats or similar components, is usually easily possible.