The Bucyrus Drag Line Excavator

From Engineering Heritage New South Wales

   To expedite the work of removing large volumes of material from the station sites in Hyde Park a large earth-moving machine was purchased from the Bucyrus Company, of Milwaukee USA. It first excavated the softer upper strata at St James, before retracing its tracks, crossing Park Street and unearthing the city circle tunnel which had been carried from Museum by mining methods. Here the flyover for the Eastern Suburbs Railway was built in the open using the Bucyrus as a long-reach crane after it had completed its earth moving task.

A wide view of the northern end of Hyde Park from the roof of the Supreme Court building, with St Marys Cathedral under construction at left. The Bucyrus is being assembled in the centre of the picture. SARA NRS 16669
The chassis sits on its tracks centre left while other parts such as the boiler, the drag bucket and other crated components are stacked ready for use. Note the use of demolished sandstone pillars from the park's fence as dead weight on the stiff leg derrick's back stays. SARA NRS 16669

   Its operation is well described by a Sydney Morning Herald reporter on 12 July 1924.

It may here be mentioned, as a contribution to the evening tramboard debates, that apparently the name Bucyrus itself has not been excavated from the Greek mythological dictionary, and owns no origin later than middle-west settlement in the United States.

   Certainly that intelligent mechanical monster, would, in the opinion of any who have seen it at work deserve some Olympian ancestry. At the St James end it has already more than paid for itself (£16,000) in reducing cost of digging. The Bucyrus, in action stretches forth a mighty arm with an iron box dangling at the end of it. Its father, one would say, was a gigantic dry-fly fisherman; its mother an elephant. Into the required direction it flings out its scraper-box as though casting for its fish; it drags it back with a true elephant’s trunk motion. Then having discovered the waiting four-ton lorry, it swings around, performs the uncurling, releasing motion which again it learned from its mother; returns, and repeats the whole operation a second time; and the four-ton lorry is fully loaded. Two other towns in the United States and one in Canada may be perhaps forgiven for hastening to acquire merit by adopting the same name as that which sent this clever toy into an admiring world.

After assembly the machine moved to Park Street and then excavated back through the park. Spoil was carried away in small lorries. Note Bradfield and other engineers standing without PPE under the path of the swinging bucket. 1 August 1922 SARA NRS 166969
To load trucks this robust hopper was devised to enable the crude machine to achieve some precision. Apparently spoil was scattered about as demonstrated by the material on the ground around the stage, as well as the workman with shovel in hand. Note the Thornycroft truck parked beneath. SARA NRS 16669

   Resident Engineer Keith Fraser wrote a report on the operation. It is contained within a larger history of the City Railway by Bradfield now held by the National Library of Australia in box 4 of ‘Bradfield Papers’.


   The “Bucyrus” Dragline was received from the ship’s slings on May 9th, and the work of erection was commenced on the 12th idem; steam was raised and excavation work commenced on the 9th June. The machine was working until 21st June in the St James area, and removed a total quantity of 2,620 cubic yards, of which 2,086 cubic yards was stacked on the side of the cutting by the machine for replacement.    The machine was then moved towards the centre of the Eastern Suburbs cutting, removing the earth mounds on each side of the central avenue en route. Of these mounds 3,440 cubic yards were removed – 2,935 being stacked, and the remainder carted away to the tip by Departmental Lorries.    On July 5th a start was made with the excavation of the Eastern Suburbs cutting, and up to the 29th idem a total of 7,690 cubic yards were excavated. For the period July 29th to August 26th, 8,641 cubic yards were removed, and 9,706 cubic yards from August 26th to September 23rd.    It was originally arranged to convey the spoil to Darling Harbour by contract. The owners of private lorries were at first diffident in taking up the work, and as a sufficient number of departmental lorries could not always be spared from the urgent work of carting cement, gravel etc., it was difficult to keep the “Bucyrus” machine working to its full capacity. However, during the period September 23rd to October 21st nine contract lorries were working, thus increasing the output from the machine to 12,029 yards for the period, with a consequent decrease of 4d. per cubic yard in the cost of excavation. This quantity was increased to 14,219 cubic yards for the period October 21st to November 18th, and the maximum of 18,490 cubic yards was reached during the period ending December 30th. For the period ending January 30th, the machine removed 13,615 cubic yards, and it finally cut out at St James Square on February 19th, after removing 12,739 cubic yards during the three weeks from January 30th.

   Thus, during its 8½ months’ work, the Dragline removed a grand total of 103,188 cubic yards. (Note: The maximum day’s work was 1370 tons. The average ratio tons – cubic yards was 1.5. 1370 tons/1.5 = 900 cubic yards approx).    The machine was digging to an average depth of 22 feet throughout, and the material encountered consisted mainly of clay with ironstone bands and shale. This material, although soft, was of an unyielding nature and explosives were used throughout to loosen it for the dragline.    The total cost for wages, explosives, and tool sharpening was £3,807.9.0, giving an average of 8.85d. per cubic yard. [9.6 cents/cubic metre]    The average cost of disposal to Darling Harbour amounted to 2/2.28 per cubic yard [27 cents/cubic metre]    If the excavation at Liverpool Street Station, where the work was done without excavating machinery, be taken for comparison the following results are obtained:-
Average rate of excavation, per cubic yard for dragline……………… ..8.85d [7.4c]

Liverpool Street……………………...................……………………… ……… …..3/10.04

Average saving per cubic yard on excavation…………… …… ….….. 3/ 1.19

Total saving on excavation of 103,188 cubic yards….£16,406/10/ 1¾. Owing to the use of Motor Lorries for disposal in place of drays, an average saving of at least 2/6d. per cubic yard was effected, giving a total saving on disposal of:- £12, 648.10.0, - this gives a grand total saved on excavation and disposal of £29,055.0.0.

Weight of spoil. In connection with the work of the dragline it is interesting to note that from the period ended September 23rd, to the completion of the work, the average weight of one cubic yard of the spoil removed amounted to 1.576 tons. After the period abovementioned, all the lorries were weighed, and there was very little variation in the average weight per month. The maximum variation being 0.2 tons above, in October. And 0.3 below the average in January 1923. The average lorry load in October amounted 5 tons 3 cwt. 3 qrs., in December 5 tons, 10 cwt., and in January 5 tons, 14 cwt 3 qrs. [4 quarters in a hundredweight, 20 hundredweight in a ton]

Coal. The average quantity of coal used by the machine from July 5th to September 23rd, when the machine was not working to full capacity, was 7.33 lbs per cubic yard excavated, but this was reduced to an average of 5.60 lbs per cubic yard excavated from September 23rd to February 19th.

Oils. The average cost of oils, waste, etc., for the whole work amounted to 0.06 pence per cubic yard excavated.

These costs are included in the average costs given above.''

   After its work at St James, there was no use for the machine at Town Hall where the site was much too restricted, or Wynyard where virtually the whole excavation was in hard rock. At the same time as the St James work ended, a Bucyrus dragline arrived at Temora to dig a large water supply dam. All newspaper descriptions, cryptic as they are, do not give any fact which would contradict the thesis that the two machines were one and the same. Any subsequent history is unknown.

The dragline digging from Park Street north towards the St James station site. The rough excavation is tidied up by 'batter men'. In the distance a truck is being loaded using the timber hopper device. 1 August 1922. SARA NRS 166969
Throughout the work public access was maintained across the middle of the park, at first by a fenced pathway and later by means of a bridge. This offered a good vantage point for the public to check progress. The gentlemen in the centre of the image may in fact be the photographer - the exposure being made by his assistant. 4 July 1922. SARA NRS 16669

With its work in Hyde Park North complete, the machine crossed Park Street to work in Hyde Park South. The stiff-leg derrick crane in the distance is on the edge of the the Museum station excavation and the City Circle tunnels have been mined from there and are about to be unearthed by the Bucyrus. 24 May 1923 SARA NRS 166969
A short section of the City Circle tunnels was built in the open using the Bucyrus as a crane. The two tracks diverge here and continue as mined tunnels. Above them will be built the Eastern Suburbs tunnels as a flyover. 20 July 1923 SARA NRS 16669

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