The Mechanical Handling and Storing of Material

COAL TIPS OR HOISTS 583 of the platform, beneath which they are passed under guide pulleys, rising from thence to the top of the tower and back to the hoist winch. The platform is raised by a combined action of the ropes until the side meets an adjustable stop which checks the descent of the counterweight. As the hoisting rope continues to pull it turns the cradle and brings the car in contact with the counterweight ropes, which hold it firmly against the rails whilst the load is emptied into an inclined shoot which terminates in a telescopic tube through which the coal is lowered and trimmed. This extension reduces bieakage and assists trimming in the ship’s hold, as it can be moved about so as to reach from side to side of the ship. The later tips on this principle (see illustration) are of sufficient size to handle loads of 75 tons, including coal and car.1 The machine is so designed as to take the truck as it is delivered by gravity at the foot of the incline, haul it into the cradle, and empty the contents into the vesssl, after which the car is led. out of the cradle on to the track for empties. It is claimed that this machine has discharged as many as thirty cars and 1,000 tons of coal per hour. The Brown-Hoist Electric Coal Tip.—Fig. 828 shows a tip, which was erected by the Brown Hoisting Machinery Co. for the Hocking Valley Railroad Co., of Toledo, U.S.A. By means of this machine the 50-ton coal wagons are picked up and emptied sideways into a large shoot from which the coal is directsd into the hold of a. vessel. 'X'he loaded truck is pushed, on the cradle—which will take any sized, truck by a car-pushing device. I'he truck is secured in position by hydraulic clamps on top and sides, then the tip is started and the cradle slowly revolves until the car is in a discharging position. During this process the material flows into hoppered compartments fixed to the cradle, each of which is connected with a transfer tube through which the material passes, these compartments being fitted with doors which are automatically rslsased on touching the lower end of the transfer tubes. Each empty car is replaced by the next loaded car coming along, and is run by gravity to the empty track, the process already described being then repeated. thirty cars per hour may be handled with such a tip. Long’s Coal Tip.—This coal tip is the invention of Mr Timothy Long, of the Excelsior Ironworks, Cleveland, Ohio, U.S.A., and has been successfully put into operation at the Erie Docks, Cleveland. The diagram, Fig. 829, illustrates the principle on which it works, although the, one at the Cleveland Docks is at a higher level above the quay than the tip shown in this illustration. This apparatus consists of a cylinder mounted at each end on rails on which it can revolve, and large enough to receive the railway truck. Within the cylinder is a continuation of the outer track by means of which the wagon enters. It is clamped in position, and the cylinder is then caused to revolve towards the shoot by means of cables and a winch. Through this partial revolution of the cylinder the wagon is tilted sufficiently to discharge the coal into a shoot or hopper, after which the cylinder is rolled back to the starting point, where the wagon again assumes its normal position and is pushed out by a full one. The cylinder is 40 ft. in length and has an internal diameter of 11 ft., whilst the outer diameter is 16 ft. It consists of a strong framework, and has openings of sufficient size for the coal to pass through in the discharging position. The capacity of this tip is stated to be three hundred cars, or 7,500 tons of coal, per 1 This tip has been fully described in a paper read by Mr J. D. Twinberrow before the Institution of Mechanical Engineers. See Proceedings Inst. M.E.. 1900, page 574.