Thickness of coatings

Curing time will also depend upon the thickness of coat and the shape of the workpiece. 

Thickness of coat This can be checked by a magnetic coating thickness tester gauge (Figure A13.5)... 

The paint is then cured in an oven. The curing time will depend upon the thickness of coat, shape of the workpiece and type of oven and its effectiveness. Generally, a coat of up to 60-70 microns at a stoving temperature of 180-200 C (depending upon the type of powder) should take around 10-12 minutes to cure. Contact the manufacturers for exact details. 

Power output and velocity controller to monitor control over quantity of powder and thickness of coat. 

Typical thickness of coating on galvanised sheet or sherardised componenis. Typical thickness of zinc plating. 

As a general guide to the thickness of coating desirable for various applications, the requirements of BS 1872 1964 for electrodeposited tin coatings are shown in Tables 13.12 and 13.13. 

These techniques are frequently used to study corrosion under coatings in neutral solutions and enjoy sporadic success, depending primarily on the type and thickness of coating being studied. 

One of the rate-determining processes on the whole NSR reaction is a diffusion of NOx and SOx in the catalyst. The thickness of coatings with a hexagonal cell substrate is almost uniform, therefore, SOx desorption of the catalyst is greatly improved with the hexagonal cell substrate compared to that on the conventional square cell. 

The determination of the thickness of the layers of fat and lean tissue in animal flesh is the most popular use of ultrasound in the food industry at present [5,6]. In fact there are over a hundred references pertaining to this application of ultrasound in the Food Science and Technology Abstracts (1969-1993). In contrast to most other applications of ultrasound in the food industry, which have rarely developed further than use in the laboratory, there are a number of commercial instruments available for grading meat quality [6, 30-32]. This application is based on measurement of time intervals between ultrasonic pulses reflected from boundaries between layers of fat, lean tissue and bone. Ultrasonic techniques have the advantage that they are fairly cheap, easy to operate and give predictions of meat quality of live animals. Other examples of thickness determinations include liquid levels in cans or tanks, thickness of coatings on confectioneries, egg shell thickness. 

The most common use of beta particles has been in the measurement of thickness of materials made in continuous sheets, eg, paper, plastics, and metal foils. Other important measurements include the packing density in cigarettes, the compn of hydrocarbon liquids, and the thickness of coatings on sheet materials by beta back-... 

At first sight the application of lacquer by dipping components into a suitable tank or reservoir might seem the simplest method but in fact it is rather difficult to control and has serious limitations. Only very simple components can be prepared satisfactorily in this way more complicated shapes with recesses and reverse angles often are not coated effectively (since their configurations can lead to the entrapment of air) or may show variation in thickness of coating. For satisfactory results, even with simple components, the viscosity of the lacquer in the reservoir must be kept constant by continuous monitoring and adjustment, and the entry and removal of the components must be very smooth, well-controlled, and uniform. 

The following example is the coating solution containing azide compound, novolak and coupler. The average thickness of coating layer was 3.7fi. All parts given are by weight percent. 

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