I 20

SHOP TOOLS.

is exerted on the top roll, so raising it, and facilitating theentering of the ingot at each passage tlirough the rolls. Atightening down screw, connected with a pinion and toothedquadrant, and actuated by a horizontal hydraulic press, iseinployed to lower the top roll. One revolution of the pinionsuffices for the whole vertical ränge of the roll. One move-ment of the handle which Controls the admission of water tothe press for lowering the top roll, serves to slacken thetightening down screws, the top roll being raised automaticallyby the pressure on the rams supporting it.

At the Elswick Works a forging press is constructed with acylinder 35 inches in diameter, to work at 3 tons per squareinch, so that a pressure of about 3000 tons is exerted. Thestroke of the ram is 9 feet, which provides for punching thecentres out of ingots. The work of punching an ingot 6 feetlong is done in two operations, and an ingot 4 feet long inone Operation. This press is served by four gas-reheatingfurnaces, and two overhead hydraulic cranes capable of handling60 tons. The total cost was about £25,000.

Messrs. Yickers & Co. of Sheffield are erecting a forgingpress, with cylinders 43 inches in diameter and about 5 feetstroke.

Messrs. Davy Brothers of Sheffield are constructing a 4000-ton hydraulic forging press for Messrs. Charles Cammell & Co.of Sheffield. In this machine two presses are employed insteadof one, with the resulting advantage of lessening the weightsand strains on the parts. The moving cross-head carrying thetool is guided by slide-blocks bored to fit the wrought steelcoluinns which support the entablative on which the pressesrest. By this arrangement the cross-head is guided indepen-dently of the pressing rams, and a forging can thus be placedconsiderably out of the mid-position between the rams, whilstthe width across the entablative can be reduced to the sinallestlimit. The sling chains holding the work are therefore able tohe brought closer than usual. A low-pressure water Service of60 lbs. to the square inch is connected to the presses, and fills