Shakers

Earlier on when we described the cutting action of the drill bit we learned about the drilling fluid or mud. The mud cools the bit and also removes the cuttings by carrying them up the hole outside the drill pipe. At the surface the mud runs over a number of moving screens, the shale shakers (Fig. 3.11) which remove the cutting for disposal. The fine particles which pass through the screens are then removed by desanders and desilters, usually hydrocyclones. 

Marklein, R. Shaker Verlag, Aachen, 1998 (Ph.D. Thesis, University of Kassel, Kassel, 1997)... 

Aqueous solutions buffered to a pH of 5.2 and containing known total concentrations of Zn + are prepared. A solution containing ammonium pyrrolidinecarbodithioate (APCD) is added along with methyl isobutyl ketone (MIBK). The mixture is shaken briefly and then placed on a rotary shaker table for 30 min. At the end of the extraction period the aqueous and organic phases are separated and the concentration of zinc in the aqueous layer determined by atomic absorption. The concentration of zinc in the organic phase is determined by difference and the equilibrium constant for the extraction calculated. 

Before polyacrylamides are sold, the amount of residual acrylamide is determined. In one method, the monomer is extracted from the polymer and the acrylamide content is determined by hplc (153). A second method is based on analysis by cationic exchange chromatography (154). For dry products the particle si2e distribution can be quickly determined by use of a shaker and a series of test sieves. Batches with small particles can present a dust ha2ard. The percentage of insoluble material is determined in both dry and emulsion products. 

Although there is no official ASTM test to measure the water handling properties of gasoline, there are a number of widely used industry tests. One uses a Waring Blender to simulate high shear (57), whereas another uses a wrist action shaker to simulate mild shear conditions (58). 

FIG. 17-58 Typical shaker-type fabric filters, (a) Buell Norhlo (cutaway view), (h) Wheelahrator-Frye Inc, (sectional view),... 

Two principal types of fabric are adaptable to filter use woven fabrics, which are used in shaker and reverse-flow filters and felts, which are used in reverse-pulse filters. The felts made from synthetic fibers are needle felts (i.e., felted on a needle loom) and are normally rein-... 

Another mechanical shaker is the End-Shak, made by the Newark Wire Cloth Co. Sieves used are Newark test sieves, made to conform with the U.S. standard series. 

A number of less expensive sieve shakers are on the market, such as the Dynamic, by Soiltest Inc., Chicago the Cenco-Meinzer, by Central Scientific Co., Chicago the Tyler portable, by W. S. Tyler, Inc., Mentor, Ohio and also a number of electromagnetic vibratory shakers. The latter should be used only when strict comparability with other tests is not required, since it is difficult to be sure that identical intensity of vibration was present in the tests being compared. 

Flour and Feed Meal The roller mill is the traditional machine for grinding wheat and lye into high-grade flour. A typical mill used for this purpose is fitted with two pairs of rolls, capable of making two separate reductions. After each reduction the product is taken to a bolting machine or classifier to separate the fine flour, the coarse produc t being returned for further reduction. Feed is supphed at the top, where a vibratoiy shaker spreads it out in a thin stream across the full width of the rolls. 

Cleanliness Hardness Hydrostatic Tests Blade Shaker (Static) Rotor balance O Standard O High Speed Final Surface Inspection Crating inspection Spare Rotor Fit ... 

To ensure that blade stress levels are within the fatigue life requirements of the eompressor, it is usual praetiee to strain-gauge the blading on one or two prototype maehines, measure the stress levels, and generate a Campbell diagram showing the plotted test data. To measure data, an impeller ean also be mounted on a shaker table with a variable frequeney output (0-10,000 Hz). Aeeelerometers ean be mounted at various positions on the... 

Initially, tests are run to identify the major eritieal frequeneies of the impeller. Mode shapes are then determined visually at eaeh of the eritieal frequeneies. To obtain these mode visualizations, salt is sprinkled evenly on the dise surfaee. The shaker is maintained at a partieular frequeney, at whieh value a given eritieal frequeney is exeited for a eertain length of time so that the salt partieles display the mode shape. The salt aeeumulates in the nodal regions. Photographs are taken at lower values of these eritieal frequeneies. Photography allows a qualitative identifieation of the appropriate mode shapes eorresponding to eaeh frequeney. Figure 5-27 shows an impeller with the mode shapes. 

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