Open Cut

Dragline Bucket Filling Investigation

Open Cut » Overburden Removal

Published: January 97Project Number: C3002

Get ReportAuthor: Terry O'Beirne, Jeff Rowlands, Murray Phillips | ACIRL

The aim of this project was to develop a method for obtaining quantitative data to characterise dragline bucket filling behaviour. This has been achieved and data has been collected for four bucket filling scenarios:

1. Conventional BE bucket (Howick mine)
2. Esco Mark IV (Newlands Mine - Dragline 1)
3. Esco Mark IV (Newlands Mine - Dragline 2)
4. BE HPS III (Ravensworth Mine - Dragline 302)

The original methodology of the project had to be altered as problems arose and practical limitations to image acquisition using automatic digital photogrammetry methods were identified.

Nevertheless the project did show that terrestrial photogrammetrical techniques can be used as a cost effective means of quantifying bucket filling behaviour.

It also successfully quantified dragline bucket filling behaviour that was previously unknown, i.e.:

  • Payload density distribution can exist throughout a bucket due to overburden and/or bucket characteristics
  • Dragline buckets may carry payload volumes significantly above their rated capacity.
  • Importantly the project also documented that significant over drag was common

In all cases the volume did not appreciably increase after 10 seconds of drag. This highlights the importance of minimising overdrag when it is possible to disengage the bucket.

An unexpected spinoff from the project may be a way of estimating minimum fill times.

Using this information to provide visual or audible warnings for operators, could significantly reduce the occurrence of costly overdrag.

The fill rates for the different buckets were essentially linear. The drag velocities for the different machines were not necessarily identical however. Trend lines for the fill rates were as follows:

  • Howick 8.75 m3/sec (time 0 to 10 secs)
  • Newlands Dragline 1 5.1 m3/sec (time 0 to 10 secs)
  • Newlands Dragline 2 4.6 m3/sec (time 0 to 12 secs)

Payload Zones

The average payload densities in the zones were as follows:

  • Zone 1: Density = 2.23 t/m3
  • Zone 2: Density = 2.09 t/m3
  • Zone 3: Density = 1.79 t/m3

These results show that it is possible to have a density distribution through the payload in a dragline bucket.

This may be due to overburden characteristics or bucket type.

The implication is that the carry angle of a bucket may be critical to performance since it is essential that a dragline should move material as efficiently as possible, ie., the bucket payload density should be as high as possible so as to move as many tonnes of overburden in the smallest possible space.

If this is achieved then the required bucket basket size is reduced (and subsequent bucket weight).

Conclusions & recommendations

This project has demonstrated a cost effective technique for gaining quantitative data to characterise dragline bucket filling.

Four scenarios have been investigated. Each yielded data that indicate a variety of bucket filling behaviours exist depending upon bucket type, overburden characteristics and operating geometry.

It appears that the payload density in a dragline bucket varies significantly between situations and that a definite density distribution through a bucket can exist depending upon overburden characteristics and bucket type.

The use of digital devices for image acquisition may not be currently possible due to the contradiction of maximising image resolution versus covering a realistic field of view.

Real time reduction of digital images to digital terrain models requires more research due to the inherent nature of dragline operational geometry and conditions.

It is possible however that low resolution application for DTMs of overburden topography (eg. Indicating that the rear of a bucket is full) could be developed from existing hardware and software technology.

With additional work on different dragline buckets and overburden types and a larger statistical universe of results the observation of variation in density distribution throughout a dragline bucket could be confirmed or denied.

Perhaps more importantly, it may be possible to develop a technique for quantifying fill times for particular buckets and overburdens thus helping to control the costly problem of overdrag.



Health and safety, productivity and environment initiatives.


Open Cut

Safety, productivity and the right to operate are priorities for open cut mine research.

Recently Completed Projects

C19024Establishing Ecologically Sustainable Mine Water Release Criteria In Seasonally Flowing Streams

Extreme rainfall conditions in the Fitzroy Catchment over an approxi...

C25030Coal Mine Open Pit Final Void Closure And Relinquishment - Addressing Uncertainty In Coal Mine Environmental Planning

This report addresses uncertainties faced by coal mine operators whe...

C27046Estimation Of True Deformation Vector From Slope Radar Monitoring

Slope deformation radar monitors are now widely used in open cut coa...

Open Cut

Coal Preparation

Maximising throughput and yield while minimising costs and emissions.

Recently Completed Projects

C27004Improving Coal Flotation With Oscillatory Air Supply

This report provides detailed information on coal flotation with os...

C25018Improving Solids Recovery And Moisture Reduction In Ultrafine Coal Dewatering

This report provides detailed information on fine coal dewatering in...

C27028Lab Froth Flotation Testing Guide With Coal Quality

Correct outcomes from laboratory froth flotation testing in coal bor...

Coal Preparation

Technical Market Support

Market acceptance and emphasising the advantages of Australian coals.

Recently Completed Projects

C26039Nanoporosity In Cokes: Their Origin, Control And Influence On CO2 Reactivity

This project using the outcomes of previous project C24060, examine...

C28063A Comprehensive Technical Review Of High-Efficiency Low-Emission (HELE) Pulverised Coal Combustion Technologies For Power Generation

Research and development has been undertaken worldwide to realise co...

C28064Carbon Structure Transformation During Coking Of Australian Coking Coals: Better Understanding The Coke Formation

Carbon structures of coke that are formed during the plastic layer a...

Technical Market Support

Mine Site Greenhouse Gas Mitigation

Mitigating greenhouse gas emissions from the production of coal.

Recently Completed Projects

C28076Selective Absorption Of Methane By Ionic Liquids (SAMIL) - Phase 2 Demonstration In A Packed Bed Reactor

An alternative approach to high temperature oxidation of ventilation...

C26004CFD Modelling Of Reverse Thermal Oxidisers For VAM Abatement - CFD Modelling Of Fixed-Bed RTO Devices

The project is part of a larger multi‐phase program of study a...

C27058Technological Assessment Of A Recycle Reactor For VAM Abatement

Underground coal mining emits high volumes of methane, diluted in ve...

Mine Site Greenhouse Gas Mitigation

Low Emission Coal Use

Step-change technologies aimed at reducing greenhouse gas emissions.

Recently Completed Projects

C17060BGasification Of Australian Coals

Four Australian coals were trialled in the Siemens 5 MWth pilot scale ga...

C17060AOxyfuel Technology For Carbon Capture And Storage Critical Clean Coal Technology - Interim Support

The status of oxy-fuel technology for first-generation plant is indicate...

C18007Review Of Underground Coal Gasification

This report consists of a broad review of underground coal gasification,...

Low Emission Coal Use

Mining And The Community

The relationship between mines and the local community.

Recently Completed Projects

C16027Assessing Housing And Labour Market Impacts Of Mining Developments In Bowen Basin Communities

The focus of this ACARP-funded project has been to identify a number...

C22029Understanding And Managing Cumulative Impacts Of Coal Mining And Other Land Uses In Regions With Diversified Economies

The coal industry operates in the context of competing land-uses that sh...

C23016Approval And Planning Assessment Of Black Coal Mines In NSW And Qld: A Review Of Economic Assessment Techniques

This reports on issues surrounding economic assessment and analysis ...

Mining And The Community


National Energy Research,Development & Demonstration Council (NERDDC) reports - pre 1992.

Recently Completed Projects

1609-C1609Self Heating of Spoil Piles from Open Cut Coal Mines

Self Heating of Spoil Piles from Open Cut Coal Mines

1301-C1301Stress Control Methods for Optimised Development...

Stress Control Methods for Optimised Development and Extraction Operations

0033-C1356Commissioned Report: Australian Thermal Coals...

Commissioned Report: Australian Thermal Coals - An Industry Handbook