Structural steel painting

These apply also to marine painting, but here additional factors must be taken into account. The present action refers specially to differences between ships painting and structural steel painting. 

Uses Anticorrosive pigment for aq. and solv.-based paints, high gloss finishes, structural steel paints anticorrosive for food-contact materi-dis... 

Protection. Forged parts, rolled structural steel shapes and plates, and castings shall be cleaned, primed, and painted with a good commercial paint or other specified coating before shipment. Machined surfaces shall be protected with a suitable lubricant or compound. 

Severe attack frequently occurs at a water-line, which in practice can range from structural steel partly immersed in a natural water to a lacquered tin can used for containing emulsion paint. This can be illustrated by adding increeising amounts of sodium carbonate to a sodium chloride solution in which a steel plate is partly immersed (Fig. 1.48c, d and e). With increase in concentration of the inhibitor, attack decreases and becomes confined to the water-line. The attack at the water-line is intense and is characterised by a triangular pasty mass of corrosion products bounded on the upper surface by a dark-brown membrane that follows the contour of the water-line. The mechanism of water-line attack is not clear, but it is likely that the membrane of corrosion products results in the formation of an occluded cell, in which the anolyte and catholyte are prevented from mixing. These occluded cells are discussed in more detail subsequently. 

Structural steels are frequently protected from corrosion by means of a paint primer, but these materials can have an adverse effect on the... 

Painting of Metal Sprayed Structural Steel, BISRA Corrosion Advice Bureau (1966) Proceedings of the Second International Metal Sprayers Conference, Birmingham, Association of Metal Sprayers (1958). (Specific references to aluminium notes in TM 420, Aluminium Federation, London)... 

The outstanding virtue of zinc-rich paints is simplicity in application. No special equipment is required and the operation can, of course, be carried out on site, large or small structures being equally suitable for treatment. While there is some evidence that the zinc-rich paints will reduce iron oxides remaining on the steel surface, proper surface preparation is as important here as with traditional paints if the best results are to be achieved. The main use of zinc-rich paints is to protect structural steel-work, ships hulls, and vulnerable parts of car bodies, and to repair damage to other zinc coatings. 

Fancut, F. and Hudson, J. C., for the Protective Coatings (Corrosion) Sub-Committee of B.I.S.R.A., Protective Painting of Structural Steel, Chapman and Hall, London (1957)... 

Paint Finishes for Structural Steel for Atmospheric Exposure... 

In general, interior steelwork is exposed to less severe conditions than exterior, but in some chemical factories the reverse is true and here special types of paint are needed. Much structural steel is encased in concrete it is therefore hidden from view and is given some protection while the concrete remains alkaline. Where the concrete is thick, corrosion may be delayed, but as the concrete becomes carbonated and particularly if it is penetrated by acidic rain water, the metal will corrode. In general it is advisable that steel which is to be encased in concrete, especially for industrial plants, should... 

Paints used for protecting the bottoms of ships encounter conditions not met by structural steelwork. The corrosion of steel immersed in sea-water with an ample supply of dissolved oxygen proceeds by an electrochemical mechanism whereby excess hydroxyl ions are formed at the cathodic areas. Consequently, paints for use on steel immersed in sea-water (pH 8-0-8-2) must resist alkaline conditions, i.e. media such as linseed oil which are readily saponified must not be used. In addition, the paint films should have a high electrical resistance to impede the flow of corrosion currents between the metal and the water. Paints used on structural steelwork ashore do not meet these requirements. It should be particularly noted that the well-known structural steel priming paint, i.e. red lead in linseed oil, is not suitable for use on ships bottoms. Conventional protective paints are based on phenolic media, pitches and bitumens, but in recent years high performance paints based on the newer types of non-saponifiable resins such as epoxies. 

Ships, lorries, cars, bridges and many other iron and steel structures are painted to prevent rusting (Figure 10.21). However, if the paint is scratched,... 

The Painting Account in this case must be low the cost of structural steel includes painting and a high portion of equipment and piping is covered with insulation. We are using the low-end on the 0.02-0.08 range. 

Placing Equipment, Paint, Foundations, Insulation, Structural Steel... 

Table VII shows three asphalt coatings used In thicknesses comparable to Industrial paints. Film thicknesses are from 0.7 to 3 mils. These coatings find wide use In Industry for the protection of structural steel, for the protection of metal parts In storage (removable with solvents), and as pipe and tank coatings. The aluminum pigmented coating has two main advantages aluminum appearance Is more desirable than black, and the pigment protects the bitumen from the actinic rays, thereby extending the life of the coatings.

Super Alkyd . [Thibant Walker] Alkyd resin for enamels, primers, structural steel coatings, traffic paints. 

An extremely fire-resistant coating material designed for spray applications to onshore and offshore oil and gas facilities has been introduced by Hempel s Marine Paints. The product, called ContraFlam 3810, is easy to apply and is particularly well-suited to the protection of structural steel work, walls, and floors. Another coating of a surface hardener/weather barrier material, such as Contraflam Topclad 3811, can then be applied followed by a color coat. 

As indicated in Table 10.18, a zinc-rich primer is often recommended. It can be an organic zinc-epoxy or an inorganic zinc-ethyl-silicate primer. Zinc-rich primers are also used as so-called shop primers, or prefabrication primers, for temporary protection of semi-manufactured steel goods. After fabrication, e.g. of welded steel structures, the shop primer surface must be cleaned (degreased), and possible shop primer defects and weld joints have to be blast cleaned and coated with a primer before the whole structure is painted. Iron oxide is also used as a pigment in some shop primers. These must not be overpainted with a zinc-rich paint. 

Automobile, Steel structure manufacturing Painting booth Toluene, xylene, esters, alcohols... 

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