The elasticity and resistance of the materials of engineering . ion to tensionas E is approached from Q. As a result of many of the experiments which have beenmade, the following mode of proportioning the head has here-tofore been very extensively used : Let r represent the radiusof the pin, while reference is made to Fig. 2. Then takeEN = The curve DRBK is a semicircle with a radiusequal to r -|- ^ with a centre, A^ so taken on the centreline of the bar that QB = o.^jw. GF is a portion of the samecurve, with ^as the centre {AC = AC); GUIs any curvewith a long radius joining 6^7^ g
The elasticity and resistance of the materials of engineering . ion to tensionas E is approached from Q. As a result of many of the experiments which have beenmade, the following mode of proportioning the head has here-tofore been very extensively used : Let r represent the radiusof the pin, while reference is made to Fig. 2. Then takeEN = The curve DRBK is a semicircle with a radiusequal to r -|- ^ with a centre, A^ so taken on the centreline of the bar that QB = o.^jw. GF is a portion of the samecurve, with ^as the centre {AC = AC); GUIs any curvewith a long radius joining 6^7^ gradually with the body of thebar. HG should be very gradual in order that there may be alarge amount of metal in the vicinity of CG, for there themetal is subjected to flexure as well as direct tension. FDis a straight line parallel to the centre line of the bar. As the preceding rule gives a head whose outline causes amore expensive die than a simple circle, at the present dayeye bar heads are usually formed as shown in Fig. 3. Art. 75.] EYE BAR ITEADF;. 647. ABD is a semicircle with a radius equal to ;* -f tor + ^, and whose centre C is the centre of the portions FA and HD are formed as before. There should be no weld across the bar in the vicinityof FH. Consequently, heads are usually formed by placingproper sized pieces upon the upset ends of the plain bars, andthen, after insertion in a heating furnace, forcing the head tothe desired shape in a die under hydraulic or steam pressure. The intensity of this pressure will affect, to a considerableextent, the permissible dimensions of the head. The greaterthe pressure, the better will be the results. The unfinished head is sometimes rolled on the bar, as bythe Kloman process. The thickness of the head is sometimes made greater thanthat of the body of the bar. If the head is circular, as in , the section of metal on each side of the pin (through AC oxCD) should be not far from eight-tenths that in the
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Keywords: ., book, bookcentury1800, booksubjectbuildingmaterials, bookyear1883
