ROLLS, BENDINO. flew?, Plate-bending Rolls.—The full-page illustration, Fig. 1, represents the No. 12 power bending rolls made by the Niles Tool Works, Hamilton. 0., for bending plates imp to 2 in. in thiekness. This machine is 22+ ft. between the housings, and has four wrought-iron forged rolls, 22i ft. long between the journals.
The two feeding rolls are placed vertically one over the other, and are :32 in. in diameter, and the two bending rolls are placed one on each side of the center rolls. These are 25i in, in diameter, and move in guides in the housings. They are so placed as to move very closely by the lower center roll when the latter is touching the upper roll. The upper feed roll runs in fixed bearings in the housing, and the lower roll runs in bearings having a vertical adjust ment of 5 in., obtained by means of heavy steel adjusting screws 8 in. in diameter, operated by tangent gearing.
The bending rolls have an adjustment of 20 in. When in their lowest position the upper surface is 4 in. below the bottom of the upper feed roll, from which position they move up ward until they touch the upper feed roll. The adjusting screws for these rolls are of steel, 7 in. in diameter. and are operated IT tangent gearing. The two bending rolls and the lower feed roll are raised and lowered by a pair of reversing engines, which are used for this purpose only. Clutches are provided in the train of elevating gear for all the movable rolls, so that either one or both ends of any of them can be moved independently. Safety friction clutches are provided in the gear train of the lower feed roll, which allow the gearing to slip when the feed rolls and plate are Dressed tightly together. Graduated index scales are provided to indicate the exact height of the ends of the rolls.
The two feed rolls are positively geared together from opposite ends. The main gear on each roll is 10 ft. diameter, 15 in. face, and 5 in. pitch. They are driven by a pair of re versing engines, whose cylinders are 12 in. diameter, and stroke 16 in. The machine is mounted on a heavy cast-iron sole plate, 18 in. deep, bedded in a massive stone foundation, and sunk to a level of 7ft. below the floor line. The plates are intended to pass through
the rolls at a height of 19 in. above the floor. The reverse levers and throttles for the engines are operated from one common platform, erected on the sole plate, level with the floor, and all clutch and operating levers are brought to a convenient position above the floor.
Vertical Plate-bending Rolls.—Fig. 2 illustrates a vertical plate-bending machine, built by Thomas Shanks & Co., Johnstone. Scotland, which is capable of bending cold steel plates 1+ in. thick, and 12 ft. 6 in. wile. The front roller is of steel, 23 in. in diameter, and is adjustable to and from the inner rollers, which are 10 in. in diameter, of forged steel. The adjustment is by two screws driven by worm-wheels and vertical worm-shaft, with bevel gear worked from either side of the machine. The forged iron nuts of the screws form the slide and bearings which carry the journals of the front roller. The machine rests on four cast iron stools, to which is bolted a strong frame carrying one end of the pinion shaft, contain ing two bearings for the back rollers, and a parallel space for the sliding block of the front roller. To this plate is also bolted a gearing frame, with the bearing for the cross-shaft and bevel pinion. These plates, with the four stools, are bolted to the masonry foundation. The top framing, carrying the rollers at the top, as also the top main pinion shaft, is cast-iron, and it is supported on a massive vertical standard, checked and bolted to the sole plates, and this forms a rigid frame to self-contain the strains. It is cast with bearings for the anti friction rollers. These are 12 in. broad, those at the sides being 10 in. in diameter, and at the back 18 in. in diameter. They are so arranged that they transfer the pressnre off the roller to the vertical standard. The inner rollers are each driven by a large spur-wheel, 31 in. pitch, worked by pinions. keyed to the connecting shaft, 8 in. in diameter. upon which also is keyed the large bevel wheel. Spur-wheels and pinions enable the gearing to be altered for heavy or light work. The engines for driving the machine are of the vertical type, hav ing 12 in. cylinders.