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Presented by :GAUTAM ANANTRAMAN K.A. GYANENDRA TIWARI

Introductiony Dragline is basically an intermittant excavator y In our country there are only about 50 dragline y It has longer reach and it requires no auxilary haulage equipment y For softer rock dragline of capacity 6 -10 cubic meter is used y Digging depth around 56m while the dumping radius 92m y Improvement over shovel: a) b) c)

stripping into the under water Works in muddy and unstable condition Stripping soft ore

Video

Parts of a DraglineBucket : Its capacity is 30 cubic meter y Boom made of made of low alloy steel tubes or steel angles, length varies from 9m to 96 m y Operators cab y Fairlead y Bucket hoist mechanism: concerned with raising and lowering of bucket y Boom hoist mechanism : a) Boom is lowered or raised by 4 part rope suspension system b) The rope is coiled or uncoiled to the boom hoist rope which is operated by a seperate motor

Parts of Draglinec) In case of smaller dragline model the ropes are revved between sheaves at the apex of the A frame and at the boom point d)In case of a larger one the rope is revved between A frame apex and sheaves at top of the mast Drag mechanism a) One end of drag rope is connected to drag drum unit and the other end connected to drag chain of the bucket by dragline yoke b) Its purpose is to handle the bucket under control of the drag controlled lever

Parts of Draglinec)The drum is a split lagging type with grooves for the drag rope d)An electrically controlled brake mounted over the pinion shaft Bucket hoist mechanism Meant for raising and lowering the bucket a) Motor provides power to the hoist drum via the gear box b) Shaft of the gearbox are connected to the hoist drum c) The hoist rope pasees round the A frame apex ,then over the sheave mounted at top of the mast over the sheave at the boom point to the dump sheave

Parts of Dragliney The brake of boom hoist drum is electrically operated

and is air released type

Parts of DraglineBoom unit It is of lattice and cross braced construction . Lower end of the boom unit is connected to the revolving unit

Video showing functioning of the Dragline(model)

Merits of Dragliney Used for handling softer unconsolidated material y Can dig well above and below grade and can excavate deep box cut y Greater digging depth and dumping radius y It has more flexibility in operation y Dragline boom length can be varied according to desire so it may or may y y y y

not require a disposal equipment Can negotiate gradient upto 12(degree) and ground pressure of 12kg/sqcm Presence of a hopper reloader helps in loading material onto belt conveyor ,rail wagon etc Maintainence is cheap Superior in wet pits

Limitation of Dragliney If the blasted rocks are of large lump causes insufficient y y y y y

filling and bucket and drag rope wear rapidly Production cost more compared to shovel Lesser spottying ability Lesser output than powered shovel Bucket fill factor is less as compared to powered shovel Lesser efficiency than shovel

Walking Dragliney Video explaining the mechanism of Walking dragline

MERITS a) It produces low presure because of its larger base area b) Turning off the machine is easy and possible in less space c) Requirement of power is less d) It does not damage the ground

Demerits of Waking Dragliney Time consuming y Could cause damage to vital features such as power line etc.

Video depicting depicting practical problems due to Walking Dragline