DRAGLINES(GẦU DÂY)

I. OPERATION & EMPLOYMENT

DRAGLINE IS A VERSATILE MACHINE

6MAIN COMPONENTS

DRAGLINE BUCKET

DRAGLINE BUCKET

EMPLOYMENT

DOES NOT HAVE THE POSITIVE DIGGING ACTION OR LATERAL CONTROL

EASY OCCUR SPILLAGE

DRAGLINE LOADING IS GREATER THAN EACH OTHERS

MAXIMUM BUCKET SIZE DEPENDS ON MACHINE POWER, BOOM LENGTH,

MATERIAL WEIGHT.

PRODUCTION ESTIMATING

USING TABLE TO ESTIMATE DRAGLINE PRODUCTION

TABLE 3.7:IDEAL OUTPUT

OF THE DRAGLINE

TABLE 3.8:OPTIMUM

DEPTH OF CUTFOR SHORT

BOOM

TABLE 3.9:SWING-DEPTH

FACTORFOR

DRAGLINE

EXPECTED PRODUCTION = IDEAL OUTPUT X SWING-DEPTH FACTOR X EFFICIENCY

EXAMPLE 3.4

JOB MANAGEMENT

MINIMUM SWING ANGLEMAXIMUM PRODUCTION IN

SHOVEL OPERATION

LIGHTEST BUCKET SHOULD BE USED

INCREASEING THE ALLOWABLE BUCKET SIZE

& REDUCE CYCLE TIME

JOB MANAGEMENT

-The most efficient digging area is located within 15 degree forward and back of a vertical line

CLAMSHELLS(MÁY ĐÀO GẦU NGOẠM)

CLAMSHELLS ARE

COMMONLY USED FOR

EXCAVATING VERTICAL

SHAFTS AND FOOTINGS

UNLOADING BULK

MATERIALS FROM RAIL CARS AND

SHIPSMOVING

BULK MATERIAL

FROM STOCKPILES

TO BINS,HOPPE

RS

OPERATION & EMPLOYMENT

2 bucket halves are forced

together by action of sheaves

Closing line is released

The counterweights cause the bucket

halves to open as the bucket is held by the

holding line

Bucket penetration depends on

bucket weight - Light

- Medium- Heavy

- With and with out teeth

ORANGE PEEL BUCKET

-ROCK PLACEMENT

-UNDER WATER

EXCAVATION

PRODUCTION ESTIMATINGUSE EQUATION 2-1

PRODUCTION = VOLUME PER CYCLE X CYCLES PER HOUR

EXAMPLE 3-5

SOLUTION OF EXAMPLE 3.5

JOB MANAGEMENT

• Continue operation

Have clamshell loading chart

• Limit load to 80% of the safe lifting capacity

• Limit to 90% for crawler-mounted equipment

Clamshell loading chart is

NOT avaiable

JOB MANAGEMENTTest maybe

necessary to determine the size

of bucket

Cycle time is reduced by

organizing the job

Keep the machine level to avoid

swinging uphill or downhill