202 



CHAPTER XI 



Fig. 98 



The size of rollers has become standardized in six-inch lengths, from 

 36 inches to 84 inches ; the corresponding diameters extend from 24 inches 

 to 42 inches, but diameters over 36 inches are very exceptional. A metric 



size which is very common in localities 

 §^^^^^^^^ where French firms have been active 



is 800 mm. by 1600 mm. 



The King and Side Cap Bolts.— The 



arrangement of the king and side cap 

 bolts varies in different patterns. To 

 each top cap there may be four top 

 cap bolts, between which pass the side 

 cap bolts ; or the positions may be 

 reversed, there being four side cap 

 bolts carried on either side of a hous- 

 ing, between which pass two king bolts. 

 All these arrangement'^ are included 

 in McOnie's patent (2444 of 1877). 

 Fletcher's patent (13397 of 1893) ar- 

 ranges either the king bolts or the side cap bolts with slots, so as to allow 

 one to pass through the other. 



The arrangement adopted in the majority of mills as now butlt is to cause 

 the king bolts to converge from above so as to meet at a point a little below 

 the bedplate, as indicated in Fig. 81. This arrangement is specifically 

 claimed in Chapman's patent (10469 of 1894), its object being to diminish 

 the width of the trash turner and to obtain 

 accommodation for larger journals without in- 

 crease of the apical angle. A similar result is 

 obtained by adopting the form shown in Fig. 



99, and also by flattening the bolts, as claimed 

 in Aitken's patent (14647 of 1897). 



Any influence of the king bolts on the trash 

 turner is eliminated by the use of U-bolts re- 

 cessed into the housing, as indicated in Fig. 



100. This arrangement is due to McOnie (patent 

 2444 of 1877), but it is usually known as Still- 

 man's, from his patent (10369 of 1900). Similar 

 in its effect on the removal of interference with 

 the trash turner is the use of T-headed bolts, 

 the heads of which co-act with the housing and 

 terminate at a location above the trash turner. 

 These designs, which call for the use of steel 

 housings, permit of the bolts being placed as 

 far apart as desired, whereby a ram of wide 

 diameter can be accommodated in the top cap, 

 allowing a decreased intensity of hydraulic 

 pressure on the ram. 



Complete elimination of both king and side 

 cap bolts is obtained b}' McNeil (patent 6228 of 1912), who forms the 

 housings with projections, which engage with counterpart projections cast 

 on the caps, as indicated in Fig. loi. The removal of the caps is effected 

 by sliding. 



Fig. 99 



