Coatings of paint

After the surface hits been prepared, the final coat of paint is tipplied. The brief procedure for painting is almost the same as for the primer tind described in Table A I 3.4. 

A thickness of up to. 50 microns is possible through one coat of primer and paint. To obtain a greater thickness an additional coat of paint, rather than primer, may be applied after almost curing the first coat. A thickness of primer of more than 30 microns is not considered satisfactory as it may diminish its adhesive properties. To obtain u thickness of up to 100 microns, for instance, each coat (one of primer and two of paint) may be around. 30-35 microns,... 

Whenever a second coat of paint is required for better adhesion of paint, it is better to rub the painted surface of the first coat w ith i finer emery paper... 

Application of protective paints consists of surface preparation of steel, priming coat and finishing coats. Wherever possible, steel should be blast-cleaned before painting. Primers thoroughly wet the metal to promote adhesion of finishing paints and carry inhibitive pigments. For example, red lead oxide will minimize the spread of rust on metal surfaces. The total thickness of fmishing coats must be at least 0.125 mm for adequate protection and life. Four coats of paint usually are necessary to achieve this. 

Farb-abanderung, /. change in color. ab-streichrakel, m. /. color doctor, -abstu fung, /. color gradation. anstrich, m. coat of color, coat of paint, -bad, n. dye bath, band, n. typewriter ribbon. 

In all cases a priming coat of paint containing some form of hexavalent chromium such as zinc or strontium chromate should be used. 

Pickle, galvanise (0-10 mm), 2 coats of paint (one on site) 350 Brushdown, spot prime, 1 top coat —after 12 years 13-7 48-7... 

Wire-brush, 3 coats of paint (two on site) 23-9 Brushdown, spot prime, 2 top coats —4 year intervals 20-2 124-9... 

Painting In mildly corrosive conditions zinc coatings will probably have a life longer than that expected of the coated article, and no further treatment of the coating will be necessary. When, however, the coating is subjected to a more strongly corrosive environment one or more coats of paint can, with advantage, be applied over the zinc. 

Adhesion the degree of attachment between a paint or varnish film and the underlying material with which it is in contact. The latter may be another film of paint (adhesion between one coat and another) or any other material such as wood, metal, plaster, etc. (adhesion between a coat of paint and its substrate). Adhesion should not be confused with cohesion (. v.). 

Figures 19.62 and 19.63 were taken at the time of investigation into a failure of 1001 of steel which should have been coated with a nearly maintenance-free system. Zinc metal spray and four coats of paint were specified but, for reasons of economy, special measures for inspection were not taken. Within months of erection areas were flaking off where millscale had not been removed (Fig. 19.62) and other areas were blistering. Figure...

There is Europe s plastic skin, 2-seat coupe, called the Smart car with molded-in color that virtually eliminates painting. The idea was to eliminate the need for three coats of paint and reducing both cost and emission problems, Project started in 1994 via a joint venture of Daimler-Benz in Stuttgart, Germany, then known as Mercedes-Benz, and the Swiss watchmaker SMH AG in Biel. They created a... 

To demonstrate the use of such a comparative cost analysis, the production of a panel was analyzed according to different processes (Fig. 9-6). In these case studies the following conditions existed (1) the panels measured 61 x 91 cm (24 x 36 in.) with the wall thickness dictated by the process and part requirements so that the weights of the panels differed (2) production was at a level of 40,000/yr. (3) the plastics for all panels were of the same type, except that different grades had to be used, based on the process requirements, so that costs changed (4) each panel received one coat of paint, except that the structural foam also had a primer coating and (5) costs were allocated as needed to those processes that required trimming and other secondary operations. 

For converting rust to clinging layers as a basis for coatings of paint and varnish, the addition of alkyl phosphates to phosphoric acid is suggested to improve its wettability and penetration [260]. 

This problem can be avoided by mounting utility outlets above the work benches. This method also has the advantage of keeping the benches clear of obstructions and easy to clean. Of course, exposed water pipes and electrical conduit do not have much esthetic value, and they are dust catchers as well. A coat of paint, however, both improves their appearance and makes cleaning easier. An even better solution is to box them in and cover them with removable panels. 

Roll coating of paint is the final process in a coil coating line. Roll coating is an economical method to paint large areas of metal with a variety of finishes and to produce a uniform and high-quality coating. The reverse roll procedure for coils is used by the coil coating industry, and allows both sides of the coil to be painted simultaneously. 

Mineral wool/cement board—Perforated and solid sheet metal and ladder-type cable trays can be completely enclosed with 1 in (25 mm) minimum thickness mineral wool/cement board panels, or equivalent. The panels should be secured with stainless steel screw and stainless steel bands in (19 mm) wide by 0.02 in (0.5 mm) thick, located no more than 18 in (450 mm) apart. In freezing climates the fireproofing panels should be given a weatherproof coat of paint. The structural strength of the metal cable tray should be adequate to support the weight of the fireproofing. 

Cathodic inhibitors promote coverage of iron by a protective coating, but this need not be an iron oxide. Immersion of iron in a solution of phosphoric acid containing a suitable catalyst causes precipitation of a mixed Fe"-Fe " phosphate film which serves as a base for a coating of paint. 

Protective coatings of paint or plastic resins are a familiar means of corrosion. control by cutting off access of water, air, and electrolytes to the structure. The coating must, however, be complete and remain intact to be protective. Local penetration of the coating will generally create an... 

A streak camera is set up with the slit parallel to the long axis of the Lucite rod a photograph like that shown in Fig. 5-12(B) is obtained. This yields the shock velocity and the free surface velocity on the same photograph. In later work it was found that a coating of paint filled with microballoons (very tiny, hollow plastic spheres) could be substituted for the argon-filled gap with equal effect. 

Facilities that use small quantities of paint and a large variety of colors often purchase paint in small cans and containers (less than five gallons) for use in spray gun equipment. After emptying the can of paint into the spray gun s pressure pot, a coating of paint remains inside the can. Since these cans are seldom cleaned, the entire can must be discarded as waste. Also included in this waste stream should be outdated or leftover paint removed from storage. Source reduction methods for this waste stream include ... 

The panel used was cut from selected poplar wood to the dimensions, 6 x 12 x 1/4 inches. Two coats of paint were applied to these panels to provide a dry film thickness of 0.004 inch. 

They furthermore assume, together with J. Bailer,52 54 that the blue pigmentation of the disinfestation chamber walls could be due to a coat of paint. To exclude this pigmentation from the analysis, they decided to apply a method which is insensitive to iron cyanides. 

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