Special Gear to Carry Big Propeller
Page 34
If you've noticed an error in this article please click here to report it so we can fix it.
QPECIAL equipment was made by Annis and ■ –./ Co., Ltd., Pump Lane, Hayes, Middx., for the
carriage this week of the world's largest propeller from the makers, J. Stone and Co. (Charlton), Ltd., Charlton, to the shipyards in Barrow-in-Furness.
The propeller, intended for a 47,500-ton Greekowned oil tanker, the biggest yet built, weighed 30 tons 8 cwt. and had a radius of 11 ft. 3 in. So that the width of the load could be kept within 20 ft.
it was carried slightly tilted in the rested position.
Near the destination, the load had to pass between two buildings only 16 ft. 4 in. apart. The table bearing the propeller had therefore to be arranged to. tilt to 400 so that the width of the load -could be reduced, to allow the Scamrnell-Dyson outfit. to negotiate this constriction.
A "dress rehearsal" was held at Charltsm a few day's before the load was due to .set off last Sunday. The apparatus built upon the 24-wheeled trailer, a former Tank transporter, took the form Of three transverSe beams welded to. the chassis. Pivoted on these beams was a frame incorporating a boss on which the propeller was to be placed.
The boss was located so that the ,averhang of the blades would be equal on each side of the trailer. Attached to one end of the frame was a longitudinal beam, at each end of which was a heavy jack. When the jacks were operated, the beam was raised and the frame inclined, so that there would be' no overhang on one side and that on the other side reduced to about 5 ft.
The propeller was lowered on to the trailer by an overhead conveyor and secured to the boss. The jacks were then wound up, the beam being raised approximately 4 ft. Elevation was a fairly lengthy process, as every inch involved 38 turns of the handle of each jack. The jacks were made up from lorry differentials and were pivoted to incline inwards as the table tilted.
When the load was inclined to afford the required clearance, the height of the outfit was 17 ft.
The idea for the special equipment was that of Mr. Frank Annis. head of Annis and Co., Ltd., and plans were drawn up by Mr. G. Hougham, consultant engineer. The gear was built in the company's own workshops.
How the propeller was to be tilted to enable a narrow gap to be negotiated. Raised like this, !here was no overhang on one side and that on the other reduced. In the resting position, the load was slightly inclined to be no wider than 20ft.
NEW INSTRUMENTS
AN oil-pressure gauge calibrated from 0-100 p.s.i. has been marketed by the Key-Leather Co., Ltd., 5 Urswick Road, London, E.9. It is 2 in. in diameter and is supplied with fittings at £2 5s. 6d.
The company also offer a temperature gauge at £2 12s. 6d. A version with an illuminated dial costs £3. It is calibrated from 40-120° C.
A32