We provide Surface Treatment Services to prepare and clean the substrate prior to coating or only for industrial cleaning reguirements – from abrasive blasting, (dry or wet, UHP – grit blasting, wet blasting, hydro blasting, ) to industrial cleaning (HPWJ/LPWJ, low or high pressure water jet cleaning, mechanical treatment/ hand-held or power tool cleaning, dust removal) or chemical cleaning and dust removal. Chech our services!
We perform the cleaning, gritblasting onshore, on site or in workshops, and offshore, new-work and repairs/conversion of of ships, industrial facilities, pipes, heavy-duty equipment, machinery
Applied to – any industry: different types of steel structures such as hulls, tanks, holds, floating dock, cistern, bunker, containers, piping, halls, for industrial equipment or heavy machinery
Dry or Wet Abrasive Blasting – Mechanical Treatment – Cleaning
- Dry Abrasive Blasting, known as Grit Blasting – more commonly known as sandblasting
- Wet Abrasive Blasting (high-powered water stream mixed with the abrasive media)
- Hydroblasting
- High Pressure Water Jet Cleaning
- Low Pressure Water Jet Cleaning
- Power-Tool Cleaning (electrical and pneumatic) (needling, chipping, brushing, bristle blasting)
- Hand-Tool Cleaning (de-scaling, hammering, scraping, wire-brushing)
- Chemical Cleaning
- Dust Removal
Mechanical cleaning
The purpose of mechanical cleaning is to remove rust, loose and intact paint as well as weld spatter. Depending on method, various cleaning grades and roughness profiles are generated.
Abrasive Blasting
Dry abrasive blasting
– grit blasting, more commonly referred to as sandblasting
Pressurized air is used to transport the abrasive to the nozzle.
The abrasive media being propelled into the surface at high-velocity to clean or etch the surface.
Most abrasive are metallic, sand, grit, and garnet blasting. Moderately abrasive are glass beads and plastic (PMB) with ground-up plastic stock or walnut shells and corncobs. A mild version is soda blasting and there are also barely abrasive and non-abrasive alternatives such as (dry) ice blasting. Abrasive is best used to create a surface profile needed for proper adhesion of coating systems. A problem is when abrasive leaves the surface contaminated. This means the less contamination abrasive leaves at the surface, the better.
Wet abrasive blasting
The blast media is moistened prior to impacting the surface to clean and strip. Water is added to the stream of air at the nozzle, or sooner.
Adding abrasive to a stream of water is also considered wet abrasive blasting.
The amount of water used may vary.
To prevent flash rusting on metal surfaces, a water based, non-hazardous, biodegradable additive called HoldTight 102 is added to the water during the blasting and cleaning / rinsing process.
Waterjetting – Water Blasting
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Low-pressure water cleaning, < 5.000 psi, 340 bar
Economical
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High-pressure water cleaning, 5.000 – 10.000 psi, 340 – 680 bar
Fairly economical
Used with and without abrasive.
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High-Pressure water jetting, from >10.000 psi, 700 bar 30.000 psi, 2.000 bar
Productivity increases
At this point water becomes supersonic, coatings come off.
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Ultra-High Pressure (UHP) water jetting, > 30.000 psi, 2.000 bar
Productivity is up
Almost every type of coating is sheared off to bare metal.
Water blasting has to be done with chloride-free water to remove unwanted materials and leave the surface ultra-clean.
High-Pressure Water Jetting (HPWJ) is a highly efficient and effective way of cleaning various surfaces. As part of your ongoing maintenance efforts, it can effectively increase the efficiency and the lifetime of your equipment.
Ultra-High Pressure (UHP) water jetting, > 30.000 psi, 2.000 bar
Productivity is up
Almost every type of coating is sheared off to bare metal.
UPH / UHPWJ stands for Ultra High Pressure Water Jet, also known as hydroblasting.
Ultra high pressure water jetting is a material surface cleaning process that uses water propelled at a high velocity to remove contaminants and other debris.
We use the force of the fast-moving water as it hits a material’s surface which is powerful enough to remove unwanted layers of old coatings. It prepares the surface for subsequent operations such as applying primers and paints.
UHPWJ is the process of cleaning a surface using water under ultra high pressure.
We adjust the pressure of the UHPWJ to provide sufficient force to remove all surface contaminants, including tightly adhering surface rust, leaving the surface completely clean.
To ensure that the surface is in fact sufficiently clean to receive a coating system, a visual assessment may be made by comparing the cleaned surface with a series of photographic standards issued by either NACE (National Association of Corrosion Engineers) or SSPC (Steel Structures Painting Council, now Society for Protective Coatings).
UHPWJ can not replace the abrasive blast cleaning for new work. Whilst abrasive blast cleaning provides a good surface profile, UHPWJ does not create a profile at all.
The abrasive blast cleaning being just about the only method that effectively removes millscale and provides a good surface profile, UHPWJ does not remove millscale nor create a surface profile.
If any millscale is present, then delamination is also very likely to occur – the performance of a coating system largely depends on bond strength between the clean steel substrate and the first coat, primer.
Coating failure generally occurs at the steel – primer interface, hence the importance of a surface profile to maximise the bond area.
The greater the profile, the greater will be the surface area and the stronger the mechanical and chemical bond. If the steel is smooth, however, then adhesion of the coating is entirely dependent on a chemical bond, which can vary enormously from product to product.
UHPWJ can replace the abrasive blast cleaning for maintenance work and repaint work over steel that had originally been abrasive blast cleaned – UHPWJ being certainly suitable. When steel that had been originally blast cleaned and painted is cleaned using UHPWJ, the process reveals the original profile, which will be just as suitable for painting as it was when originally blast cleaned. Therefore, the all-important profile is already there ready for the new coating system to key into.
Ultra high pressure water jetting does not use hazardous chemicals. Despite the advantages, the recovery system for the water is important because some surface debris can be hazardous to the environment and may need to be contained and disposed of in accordance with environmental laws.
Hand and power tool cleaning
Hand and power tools Remove oil and grease by fresh water washing with a suitable detergent followed by fresh water rinsing to remove remaining salts and other contamination. Solvent cleaning may also be applied for small areas. Clean to bare steel in the selected areas according to the cleaning grade as specified in the specification or Product Data Sheet of the product to be applied. Feather around the edges and roughen the area of intact paint around the overlap zone of the repair with a suitable hand tool. Finally remove any remaining dust before applying the new paint.
Hand tool cleaning
The hand tools cover a wide range of wire brushes, scrapers, spatulas, synthetic abrasive pads and manual chipping hammers. The tools are very easy to use and ideal for smaller areas and irregular constructions.
Power tool cleaning
Productivity exceeds hand tools slightly, yet remains relatively low.
Power tools include pneumatic or electrical options and encompass various rotating wire brushes, grinders, and needle guns.
On the other hand, simpler manual tools are user-friendly and well-suited for smaller or irregular constructions.
The Society for Protective Coatings established three power tool cleaning standards:
SSPC- SP 3, SP 15, and SP 11.
While each of the three standards invokes the use of power tools, the degree of coating removal and surface roughness requirements vary.
Cleaning grades
The cleaning grades possible to obtain are:
• St 1: Not relevant – unsuitable for painting
• St 2: Thorough hand and power tool cleaning
• St 3. Very thorough hand and power tool cleaning.
Roughness
It is not possible to achieve a roughness profile that is higher than finer than fine with hand tools In generaL.
Only for certain power tools, such as a “bristle blaster”, a fine roughness profile of about Rz 25-40 µm can be achieved.
After cleaning to grade St 3, it is of outmost importance that polished areas are roughened with coarse sand paper, grain size about 40, before painting.
Finishing treatment
Clean solvent-wetted rags are used to remove dust and other remaining loose contaminants for small areas. For larger areas, brushes or vacuum cleaners.