Division - Metal Protection

Protection of Metal Structures and Machine and
Technological Devices

Repair and protection of metals against corrosion, erosion, abrasion, cavitation
and chemical effects is one of the most progressive and effective activities of our
company. The use of polymercomposite materials is the most effective way how
to protect metals against the mentioned negative effects.

In this area, from the long-term perspective, it is possible to save the majority of
means at the maintenance of machinery and technological equipment.
A progressive method of protection of metal materials by polymercomposites fully
substitutes previous methods as gumming, lamination, application of coatings
with short life and so on. Contrary to lamination, polymercomposites are characterized by adhesion to a material, which is several times higher, which is valid also for characteristics of tensile strength, pressure in bend, so no spalling or tearing occur at higher pressures or any other mechanical load.

The life of this material exceeds the life of original material several times; the company usually offers a minimum guarantee period of 5 years. The lifetime of such a material is estimated to 10 – 12 years.

Our company has repaired ten thousands square meters using this technology.
Effectiveness has been increased and costs for routine maintenance during periodical shutdowns of production have been reduced. With the use of polymercomposites, the surface has high resistance against negative effects causing degradation of metals after it has been reconditioned. A high bright surface reduces
frictional resistance, improves flow of liquids and efficiency of pumps.

There are examples of many areas of use:
- tanks for chemicals and other products with pH of 1 - 14, condensing tanks
  for turbine generators in the area of power engineering,
- pipelines, tanks, welds of tanks made of stainless steel in primary circuits
  of nuclear power stations, silos for fly ash or concrete, vacuum pumps,
  moving wheels, reaction vessels, spiral pumps,
- heat exchangers, exhaust pipelines for gases, fans, chimneys,
- for external structures, as coatings of tanks, structures in highly loaded
  environment, structures demanding protection against UV radiation,
- special applications in area extremely loaded with cavitations and abrasive
  effect of a flowing medium, as for example drives for blades of turbines and
  pumps of various sizes and diameters, draft-tubes and other parts of
  pumping systems.

A multilayer coatings for protection of devices and metal structures against
corrosion can be applied also in extremely corrosive environment or for difficult,
wet, permanently wet conditions, as ships, equipment in docks, bridges, pressure
pipelines, holding vats exposed to atmospheric conditions and others.

Nuclear Program

In most cases the technological equipment in nuclear power plant’s primary
circuits is made of stainless steel. The tanks which are laid with concrete are lined
with stainless flush plating.

During the planned overhauls and subsequent inspections of the stainless flush
plating it was found that individual welds had a weld root not welded, leading to
the leakage of a liquid medium.

The system of re-packing of welded joints meets the strictly demanding
requirements of legislation and of the operation of nuclear power plants.

This system was tested and approved by state authorities of the Nuclear
Regulatory Authority and the National Occupational Safety Office as a system of
protection of welded stainless joints against leakage of active liquids. This layer
coating system of sealing welding joints method is patented and awarded by the
Industrial Property of the Slovakia.

Our company offers full warranty and post-warranty service with technical
inspections and repairs.

This system:
- is many times resistant to nuclear radiation
- is very easy to decontaminate
- is 100% efficient against leakage of active liquids
- minimizes the time required for repair of joint leakages
- is unusually compact and in case the base material peels off the resin does
not fall off or contaminate the environment.

Our company offers to you:
- Inspection of the original state of the stainless flush plating
- Elaboration of technical documentation and of the project
- Implementation in non-stop operation in multiple shifts of highly qualified staff
- Continuous control of the quality of work implemented
- Independent inspections focused on efficiency of re-sealing
- Elaboration of supplied technical documentation
- Formulation of final test protocols

Between 1999 – 2009 Chestreal accomplished ca 5050bm of welding joint sealing
and treated ca 3000m2 of stainless surface in the primary circuits of nuclear power
plants.