Wash boring

Wash-boring rig. (a) Driving the casing, (b) Advancing the hoie. 

United States, it rarely has been employed in Britain. This is mainiy because wash boring does not lend itself to many of the ground conditions encountered and aiso to the difficuity of identifying strata with certainty. 

The field vane shear test can be undertaken in boreholes formed by cable tool and wash boring methods. It is used to measure the shear strength of soft clays and clayey silts by means of a small vane, which is pushed into the soil. An increasing torque is applied to the vane until the cylinder of soil fails at which point the applied torque is noted. It is often the only way in which the shear strength of very soft soils can be measured reliably because of the difficulty of obtaining and testing truly undisturbed samples in such material. 

This tube is connected %vith rubber tubing of about 6 mm. bore to the carbon dioxide Kipp, via a wash-bottle containing sodium carbonate solution (to remove any dilute hydrochloric acid spray). It is very important, when the apparatus is in use, that there should be no constriction or bend in the rubber tube between the tap C and the wash-bottle. If these precautions are taken, a slow, e en, and easily controlled flow of gas can be obtained. 

Petroleum and Goal. The alkanolarnines have found wide use in the petroleum industry. The ethanolamines are used as lubricants and stabilizers in drilling muds. Reaction products of the ethan olamines and fatty acids are used as emulsion stabilizers, chemical washes, and bore cleaners (168). Oil recovery has been enhanced through the use of ethan olamine petroleum sulfonates (169—174). OH—water emulsions pumped from wells have been demulsifted through the addition of triethanolarnine derivatives. Alkanolarnines have been used in recovering coal in aqueous slurries and as coal—oil mix stabilizers (175—177). 

Another option is to use open filters, which are generally constructed in concrete. They are normally rectangular in configuration. The filter mass is posed on a filter bottom, provided with its own drainage system, including bores that are needed for the flow of filtered water as well as for countercurrent washing with water or air. 

After standing about three hours, the diphenylamine hydrochloride is filtered and washed with benzene (Note 10). The benzene is distilled from the filtrate (Note n) and the residual triphenylamine is transferred to a 500-cc. modified Claisen flask (Org. Syn. 1, 40) and distilled under reduced pressure. The first fraction consists of some benzene, then the temperature rises rapidly and a few cubic centimeters of deeply colored distillate comes over just before the amine fraction, which is collected at i95-205°/io-i2 mm. The distillate is a yellow liquid which soon solidifies to a light yellow solid. The side arm of the distilling flask should be of rather large bore (about 10 mm.) to prevent clogging by the amine which solidifies. The crude product weighs 220-235 g. and melts at 120-124°. 

Best Preparation on a Laboratory and Commercial Scale. A. Methylene diform amide. In a 2fi round bottom 1 neck flask are placed 540g of formamide and 70g of hexamine. The flask is fitted with a wide bore air condenser topped with a w jacketed reflux condenser, and the flask held at 140 for 5 hours. It is chilled in ice, the solid filtered, and washed on the filter with 90g of formamide. The cmde prod may be used in the next step. For a pure sample,- the crude solid is dissolved in et ale, decolorized with charcoal, and the soln chilled, mp 142—43°... 

In nondispersed systems no special agents are added to deflocculate the solids in the fluid. The main advantages of these systems are the higher viscosities and the higher yield point-to-plastics viscosity ratio. These alterated flow properties provide a better cleaning of the bore hole, allow a lower annular circulating rate, and minimize wash out of the bore hole. 

Acid washing is used to dissolve acid-soluble scales from the well bore and to open gravel packs and perforations plugged by such scales. 

Since over-ozonisation must be in any case avoided, attach a second wash bottle containing acid potassium iodide solution to the outlet tube of the first before the calculated time has elapsed. If no ground glass joint1 is available, use a long bored cork stopper which has been dipped in molten paraffin wax. 

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