No_3_March_1969 — Page 45

contractors

plant

HAND WINCHES

David Round and Son, Inc., PO Box 9557, Solon, Ohio, USA, have developed hand-powered winches of 5 tons and 2 tons capacity designed for either horizontal or vertical winching applications.

Each has drop-forged cut-steel gears, sealed ball bearings and an ex- tendable crank with ferrule grip to per- mit leverage and rotational speed to be adjusted for a specific job. A band type lever brake is fitted and a tail yoke for truck mounting is available.

Model 99 will lift 5 tons using com- pound gearing or 1,500 lb. at rapid lift.

Round model 99 winch

SA TOOL I

Pull required is 35 lb. The rope capa- city of the drum varies from 175 ft. of 5/8 in. rope to 485 ft. of 3/8 in. rope. Model 99 Junior requires a pull of only 16 lb; its drum accepts 80 ft. of 1⁄2 in. rope to 380 ft. of 4 in. rope.

BREAKING TOOL

Useful where explosives or a ball drop are prohibited or impractical, the type 10 Roc-Jak is an effective tool for the demolition of open-face rock or

mass concrete.

It is inserted into a pre-drilled hole and in less than two minutes 150 tons of hydraulic pressure makes a clean break in the material at right angles to the point of thrust. The material can be broken in any size.

In operation, oil pressure forces

С

Type 10 Roc-Jak

body against the wall of the hole. After the break the pistons are retract- ed by opening two valves. The body of the tool is 61 cm. long and 7.6 cm. in diameter. It is constructed of heat- treated, precision-ground steel. The breaker pistons are fitted with neoprene cups and are deisgned to withstand 1.055 Kgs/cm2 pressure.

K.O. Duncan Co., PO Box 504, Boulder, Colorado, USA, are the makers.

TRENCH CUTTER

Savings in the costs of digging trenches for carrying water, oil and gas are claimed for the Colman trencher which weighs only 300 lb. and can be transported in a small van.

To operate the machine, a cable is fixed to a stake in the ground and the machine draws itself along by means of a built-in winch powered by a four- stroke petrol engine. The 46,000 lb.

ten pistons outward from the Roc-Jak Colman trencher

breaking load of the digging chain en- ables the machine to be used in heavy soil.

Four digging speeds can be changed while the machine is moving. Gouged- out soil is deposited to one side by a worm auger. The makers are Colman Industrial, Ltd., East Street, Sudbury, Suffolk, UK.

SCAFFOLDING

U.B.M. Scaffolding Ltd., Winter- stoke Road, Bristol 3, UK, are marketing a scaffold tower system that accommo- dates both static and mobile towers and by the simple addition of bridge pieces doubles as a continuous plat- form scaffold.

The bridge units which convert two or a series of towers into a continuous platform scaffold are in 16 ft. and 8 ft. lengths. Pavement frames allow free pedestrian access under the scaf folding tower.

The basic components of the towers are rigid frames with verticals formed

UBM mobile tower

8 ft.

of 2 in. OD tube in two sizes by 2 ft. and 5 ft. by 2 ft. There are no loose fittings and a 20 ft. tower can be erected in about ten minutes by two men.

POLYTHENE FILM

A high-tensile polythene film has been added to the range of products made by British Cellophane Ltd., Twickenham, Middx., UK. It is called Tensiltarp.

In addition to its increased strength, the material is said to have all the ad- vantages of conventional polythene tarpaulin waterproof, windproof, resistant to tears and punctures, oil- resistant, and easy to store and handle. Its uses will be primarily as a long-life protective material in building.

Far East BUILDER, March 1969

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