ROLLING-MILL. 



Jg. 3. The wheel at the other end of the foaft, k, (fee 

 Jg. 2.) turns the wheel f, fituated direftly above it ; and 

 this gives motion to two wheels, e and g, of the fame di- 

 meniions as a and e. Their axles, L and K, are connected 

 with the upper of each pair of the rollers. By the intro- 

 duction of the wheel f, the fmall wheels, e and g, are made 

 to revolve in a contrary direction to the wheels a and c ; and, 

 at the fame time, the centres of the former are raifed a fuf- 

 ficient height above the latter, to allow for the difference in 

 height of the centres of the upper and lower rollers of each 

 pair. The coupling-boxes, L K and pp, which unite the 

 axles of the wheels to their refpe&ive rollers, have fufficient 

 play in the joints to allow for that fmall deviation which 

 takes place in feparating the rollers, to adjuft them to dif- 

 ferent thickneffes of the metal they are intended to roll ; 

 though thefe (hanks mould be reprefented longer than the 

 limits of our plate have allowed, the fpace between the 

 frames for the wheels being in reality eight feet, inftead 

 of five feet nine inches, as given in the drawing. 



By this arrangement of the wheels of the mill, the con- 

 trary motions of the two rollers are communicated from the 

 fame water-wheel, without the intervention of fmall pinions, 

 which, in works requiring fuch heavy ltrains as that of roll- 

 ing iron, always work with difficulty and enormous friftion ; 

 fo that they break and wear out conftantly, making great 

 interruptions to the work. In the prefent inftance, the 

 wheels are all of confiderable fize, and, therefore, tranfmit 

 the power more equably, at the fame time that they give 

 the two rollers precifely the fame velocity, which is a cir- 

 cumftance of fome importance in making good rolling for 

 plates or bars, which will be irregular, if one roller turns 

 fafter than the other, in confequence of one fide of the metal 

 being more expanded. The framing of the mill (Plate IV.) 

 is very clearly exprefled by the drawing. The axles H 

 and I, of the wheels a and c, arc fupported in bearings, 

 fcrewed down to iron frames, which are fecurely fixed to 

 the folid mafonry. On the other fide, the iron frame, O O, 

 is erected to fupport the axles of the wheel L K, and alfo 

 that of the wheel f, as (hewn in Jg. 2. The main axis k, 

 and the wheels upon it, are carried under ground, and fup- 

 ported on the walls, as (hewn by the plan. The roller- 

 frames, CD and E F, (Jg. 1.) are fixed down upon 

 ftrong beams, extended acrofs from the frame, O, to the 

 frame on the oppofite fide. The pofition of one of thefe 

 beams is (hewn by dotted lines on the right-hand fide, in 

 Jg. 1. The rollers, C, D, are exactly the fame as (hewn 

 in Plate V. Jgs. 3, 5, and 6, except that the pinions, d 

 and e, are omitted, being unneceffary, from the arrange- 

 ment of the wheels, which we have defcribed. The other 

 rollers at E F are made on a very different conftru&ion, 

 and are called (litters, becaufe they (lit or cut up a bar of 

 iron into feveral fmall fquare bars, of a fize proper for nail- 

 makers, or to form hoops for barrels. Thefe flitters con- 

 fid of two ftrong axles, mounted in a fimilar frame to the 

 other rollers ; but inftead of carrying plain cylindrical 

 rollers, they have rollers compofed of fteel rims or edges, 

 of the fame breadth as the rods they are to (lit, and leaving 

 between them deep grooves. The two flitters, or cutters, 

 are fo placed in their frame, that the rims of one roller will 

 enter into the grooves between the rims of the other. This 

 will be underltood by an examination of Jg. 4.. Plate V. ; 

 though the rollers there (hewn are for a totally different 

 purpofe, (till the manner in which the rings of one roller 

 enter the grooves of the other is the fame as the flitters : but 

 the proportion of breadth is different, the (litters being made 

 with grooves of half an inch, three quarters, or one inch 

 wide, and many intermediate fizes, correfponding to the 



rods to be cut ; and they are not made from a folid roller, 

 but are formed of feparate circular plates of fteel of the juft 

 thicknefs, fitted fide by fide upon the axis, with circular 

 iron plates of equal thicknefs between them, which form the 

 fpaces ; and being of a lefs diameter than the fteel plates, 

 or cutters, they leave deep grooves between the edges. A 

 number of crooked guide-bars are extended acrofs the frame, 

 and pafs through the grooves, between the cutters ; but 

 lying at the very bottom of the grooves, and not being very 

 thick, they do not fill up the grooves, the circles of the 

 cutters projecting through thefe bars, which appear like a 

 grate, and one is applied to each roller. Thole which are 

 called the guides of the flitters are intended to prevent the 

 iron adhering in the grooves between the rims, or cutters, 

 when preffed down into them ; for the aftion of the (litters is 

 to divide the iron which is palled through them into fepa- 

 rate pieces, by the rim of one roller (for inftance, the lower' 

 forcing one piece of the bar down into the groove of the 

 lower roller, whilft the adjacent part is forced up, by the 

 rim of the lower roller, into the groove of the upper : the 

 bar is thus divided into as many rods as there are grooves in 

 the width which it covers. The angle at which the circles 

 of the cutters interfed each other, is that in which the 

 edges of a pair of fhears are found the moft favourable for 

 cutting ; and the (litters cut upon the fame principle, but 

 with feveral edges at the fame time. 



A rolling-mill generally contains a pair of fhears, of a fuf- 

 ficient ftrength to clip off the ends of the largeft iron bars, 

 to reduce them to lengths or pieces of a fufficient fize 

 for laminating into thin plates. Thefe are made different 

 from other kinds of fhears, in the circumftance that the cut- 

 ting parts, or edges, are fituated between the centre pin or 

 joint, and the part or handle where the powtr is applied : 

 the latter is of great ftrength, and made exceeding ftrong 

 in iron. The (hears are fixed in a vertical pofition, the 

 upper blade being firmly fixed by the framing, and the lower 

 one, which is the long lever, is lifted up by the mill when 

 the cut is to be made ; therefore it defcends when the 

 fhears are to open, and its own weight is fufficient for that 

 purpofe. The frame confifts of a very large and thick iron 

 plate, which is fecurely bolted down to the foundations : at 

 one end is an upright, which has a groove through it, to re- 

 ceive the moving blade, and guide it ; alfo the end of the 

 handle of the ftationary or upper blade is fupported by the 

 upper end of this upright. The joint-pin of the two blades 

 is fupported in a ftrong focket, or iron frame, alfo erefted 

 from the fame large plate, which carries the upright guide 

 at its other end. The two blades, therefore, lie fide by 

 fide, and having cutters, or blades, of fteel, let into the ad- 

 jacent fides of the iron levers or blades, the edges of thefe 

 pafs by each other when the cut is made, and will thus 

 cut any thing which is interpofed between them, in the fame 

 manner as fhears or fciffars ; and in this circumftance is their 

 only refemblance to thofe inftruments. The lower or mov- 

 ing blade, which is a long lever, refts at the extremity, 

 upon the periphery of an elliptical wheel, or camm, ( Jgs. 1, 

 and 3.) fixed upon the axis, I, of the rollers, (or, in other 

 cafes, upon the (haft of the water-wheel,) in an excentric 

 manner, fo that, in turning round, it will lift up the lever, 

 and clofe the (hears ; but when its oppofite or (horteft 

 radius comes beneath the lever, it is fuffered to defcend, and 

 open the blades. At this moment the workman introduces 

 the end of the iron-bar between the blades, pufhing the end 

 of it up to a flop, which regulates the length to be cut off; 

 then as the camm turns, it clofes the blades, and cuts at 

 once through the bar, although fome of the largeft are as 

 much as three inches broad, and an inch thick. 



7 Roller. 



