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API TR 13TR3-2018 pdf free download

API TR 13TR3-2018 pdf free download.Size Measurement of Dry, Granular Drilling Fluid Particulates.
Laser diffraction, also referred to as static laser light scattering, is one of the most common measurements for determining particle size analysis and is the current dominant method for measurement of finer granular drilling materials. The fundamental measurement of LD results from light diffraction patterns created as particles pass by a laser as either a dispersed dry powder or, more commonly, as particles suspended in a liquid carrier fluid. The light scattering produces a total raw diffraction pattern of the entire population of particles; this method results in an ensemble measurement of all the particles in the sample. Laser diffraction is typically performed by dispersing the particulate sample in a liquid medium and passing the dispersion through the laser light field, wherein the light diffraction (scattering) angle is measured to interpret particle size in terms of an equivalent spherical diameter. There are several different analytical interpretation techniques that can be applied to the raw diffraction pattern that will impact the measured dimensions reported. Both an advantage and a disadvantage of the method is that wet LD typically uses a very small amount of sample, which must be effectively dispersed in the transparent medium (fluid). Dry laser diffraction typically uses more material (several grams). The percentage of the laser light being scattered is dependent upon the concentration of the sample in the transparent medium. This concentration must be optimized to permit effective measurement because concentrations that are too high will result in multiple scattering (which delivers a false lower reading of the size). Conversely, a concentration that is too low will result in poor accuracy because of low signal and poor statistical representation of the particle population. Dispersion of the sample in the medium can be optimized by the use of surfactant/dispersants, agitation, and sonication.
Laser diffraction is the current standard PSA technique for conventional drilling fluid particulates, including barite, bentonite, and drilled solids. Laser diffraction is most accurate with granular materials having low aspect ratios and material blends comprised of components having similar relative density (specific gravity). The effective particle size range for this technique, depending upon equipment configuration, is quite broad. The effective size range of wet LD extends from 0.01 µm to around 3000 µm. For dry LD, the effective range is typically 0.1 µm to 3000 µm. NOTE With anisometric materials, the LD effective range is typically reduced to 1 µm to 1 00 µm. Image Analysis (IA) This method utilizes sophisticated optical microscopy coupled with digital analytical software to provide a visual representation of the particles and analysis of shape and size of the particles. Two techniques, static and dynamic, are available. In both cases, the sample is dispersed across and between a uniformly back-lit field and a highly pixilated charge coupled device (CCD). The sample particles block (eclipse) light from the illuminated platen, preventing or reducing the light that reaches a group of adjacent pixels on the detector. The maximum number of adjacent (eclipsed) pixels and the optical magnification of the system employed define the length of the measured dimension. Image analysis is also often used for determining information on particle shape. Large numbers of individual particles can be measured at once by CCD detectors with very high pixel counts. Various (and generally proprietary) statistical methods are then employed to process the data and define the size and shape attributes of the individual particles. Static IA methods measure static particles, but move the imaging device around to measure different particles. Dynamic IA methods continuously pass mechanically dispersed particles (in air or clear diluent fluid) between the back-lit field and the CCD detector.

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