Workshop Techniques
General information
Blasting is used for the removal of rust, paint layers and mill scale, old paint layers among other things.
In most cases, blasting is carried out as a pre-treatment before conservation, in order to obtain the desired cleanliness and roughness of the surface to be treated.
Blasting is a fast and efficient way to clean and roughen the material. This is done by spraying a blasting agent against the surface under high pressure.
Roughening is necessary to obtain a good anchor profile. The anchor profile is important to create good adhesion for a new coating to be applied.
Materials treated by us include: steel, cast iron, aluminium, stainless steel, wood, glass and hot-dip galvanized steel.
In the factory this is always done under controlled conditions. By using various types of abrasive, it is possible to achieve different degrees of roughness and cleanliness.
The required degree of cleanliness will be applied based on your specific wishes and in accordance with the requested conservation work.
The following cleanliness grades can be used depending on customer and conversion requirements:
- SA 1
- SA 2
- SA 2½
- SA 3
This can be checked with:
- ISO 8501-1 :1988 Pre-treatment of steel for the application of paint and related products. Visual assessment of surface cleanliness.
- Elcometer ISO 8503-1 Blasted Surface Comparison Test.
The higher the SA value, the cleaner the material. We indicate the roughness in microns. Depending on the material to be blasted and the required roughness and cleanliness,
we choose the right abrasive in consultation with the client. We work with cast iron, corundum, vasesil, ceramic pearls and sand in various coarsenesses.
Grit blasting
Blasting is done by blowing fine grit against the material with high pressure, which removes the paint layers, rust or mill scale. The pressure is varied for different materials.
This creates a surface that can be further processed by different coating systems. The blasting can be done by different types of abbrasive to achieve different degrees of roughness and cleanliness.
Braspenning has various blast halls available up to a maximum length of 40 metres.
Ceramic pearling
We started ceramic beading in 2015. Ceramic beading is mainly applied to stainless steel and aluminium, using a ceramic abrasive. This produces an even appearance whereby any discolorations
caused by welding or heating disappear. The difference with glass beading is that the finish is much smoother, making the surface easier to clean and less dirt adhesion.
The sensitivity to corrosion and staining is also considerably less. Ceramic beading is widely used in the food industry. Due to the beautiful, smooth, matt silver finish, this finish is also very suitable
for the design industry.
Ceramic beading vs. glass beads:
• Smoother finish – surface roughness: 0.7-1.2µm.
• Smooth, matt silver finish. • Grain size abrasive approximately 100µm.
• Less susceptibility to corrosion and staining.
Glass bead blasting
Glass bead blasting is a blasting technique that is used to improve the mechanical properties and to achieve an even surface. Glass bead blasting is done by blowing glass beads against the material with a
varied pressure. Glass bead blasting is usually performed on stainless steel and aluminum, but also on steel to create a finer profile.
Spray painting
The coating is applied immediately after blasting of the material. When spray painting, several layers of paint are usually applied, depending on the required layer thicknesses and regulations.
For this, we only uses top quality paint from renowned paint suppliers. These paint layers are applied both with high pressure (airless 50-350 bar) and with low pressure (hvlp 1-5 bar).
Of course everything under controlled conditions, by professionals and under the supervision of our coating inspector.
Metallizing / Thermal Sprayed Aluminum (TSA)
Blasting company Waterland/Amsterdam has more than 40 years of experience with metallising / thermal sprayed aluminum. Metallizing is the application of a layer of metal by means of flame spraying
or an electric arc. In both cases, a metal in the form of a wire is sprayed (melted) with a flame on the blasted material. This is possible with different metals / alloys, for example; zinc, zinc-aluminium 85%-15%,
bronze, copper, stainless steel or pure aluminum (99.5%).
This significantly extends the life of the treated material (up to 50 years depending on the layer thickness). This process is used for various purposes. For example against corrosion, but also as cathodic protection.
Bronze and copper is widely used in offshore lifting hooks against sparks (anti static). Metallizing / TSA is comparable to hot-dip galvanizing.
Advantages of metallizing / TSA compared to hot-dip galvanizing:
• workpiece dimensions are unlimited.
• can also be done on location
• material does not warp during process.
• good surface for coating (is rough).
• looks smooth (no drips or zinc nests).
• has very good adhesion to blasted surface (more than 20 mpa is possible).
Projects realized by Straalbedrijf Waterland/Amsterdam include: lock gates, crane parts (offshore EOS-Pluto project Woodside), bridges, pressure vessels for wind tunnel, fencing, etc.
Straalbedrijf Waterland/Amsterdam has several metallizing units that can also be used on location. We work for and together with various blasting and powder coating companies.
If it is not possible to metalliz in our factory (the object is too large or too heavy), a solution will be sought in collaboration with other companies.
