Catalyst of change
With a burgeoning economy driving high construction rates, the Asian excavator sales market is buoyant, but highly competitive. The market for heavy excavators has been extremely healthy in recent years and with abundant opportunities.
Caterpillar recently undertook a comprehensive comparative excavator production study test against another high selling brand to equip dealership staff with the facts when it comes to performance. Leading the study undertaken at an aggregate quarry was Caterpillar Large Excavator Product Specialist.
Fuel economy is probably the leading decision criterion in excavator selection but the research group discovered some confusion in the market and a sheer lack of understanding on excavator productivity measurements. The excavator competitive test measured productivity in very closely specified excavators and presented results — tonnes per hour, tonnes per litre burned and litres per hour collected via fuel flow meters and weigh scales on the quarry site.
In the first study, a Cat 349D LME was pitted against the similarly specified and weight competitive machine. The Cat has 10% more power and increased hydraulic flow from the same displacement engine.
Both machines were fitted with approximately 2.6m3 buckets. The extra power and hydraulic flow of the Cat 349D LME also allowed a larger 3.2m3 bucket to be attached to allow a further test of the machine’s fuel efficiency and productivity. Fitted with a 2.6 m3 bucket, the 349D LME outperformed the competitive machine with a 6% improvement in productivity in Standard Power (SP) mode and marked 9% better productivity when fitted with the larger capacity 3.2m3 bucket and operated in SP mode as compared to the competitive machine in the same mode.
For customers interested in productivity gains the 349D LME with a 3.2m3 bucket provided a great result with up to 18% improvement in productivity in Cat High Horsepower (HHP) mode and 9% improvement in fuel efficiency when operated in Economy (Eco) mode.
Another phase of the test pitted a Cat 340D LME fitted with a 2.69m3 bucket against the more powerful competitive machine.
It was a smaller machine fitted with a larger bucket and it delivered almost the same productivity (-2%) as the competitive machine but with a 16% improvement in fuel efficiency in HHP mode.
Similarly, for customers more focused on fuel consumption a 340D LME fitted with a 2.69m3 bucket delivers almost the same productivity as the larger competitive machine but with up to 14% less fuel burn when operated in Eco mode.
The research group concluded that choosing the right machine for the task combined with the correct bucket was critical in excavator sales in any application.
The study also pitted a popular Cat 336D2 against a competitor’s machine with the same bucket size but was 4 tonnes heavier.
The 336D2 features advanced engine controls and hydraulic flow control, which is designed to deliver up to an 8% improvement in fuel consumption compared to the 336D, under similar working conditions.
This study illustrated the Cat 336D2’s fuel performance — burning a comparative 4% less fuel than the competitive machine operating in their respective HHP mode. The Asian excavator market has welcomed the model Cat 336D2 which now consumes up to 8% less fuel than its predecessor but maintains the same power and performance. According to the group, Cat publicised hydraulic power figures in the excavator market and the productivity study also checked all the tested machines’ net engine power against the actual hydraulic power produced. For an excavator, hydraulic power is the heart of the machine and is actually doing the work.
The group also concluded that Cat excavators are efficient at converting mechanical power into hydraulic power and the study showed that the 349D LME converted engine power to hydraulic power at a rate of 86.1%. That compared to the competitive machine in the same class operating at just 79%.
The 340D LME converted engine net power to hydraulic power at a rate of just over 90%, as did the 336D2. This compared favourably to the competitive machine that converted at a rate of just 82.8%.
Cat machines are noted for their productivity in Asia, according to the group. In harder digging or difficult tasks, Cat was a preferred choice, but for customers in lighter duty tasks who are focussed on fuel economy it could now be proved that selecting the right Cat machine will deliver the results they are after.
The productivity study also highlighted that significant productivity gains would also be available to construction, mining and quarrying operations with the implementation of better haul truck and excavator fleet matching and load cycling. Productivity improvements of this style are quite a difficult sell to many companies but there are significant gains to be had by implementing simple haul fleet management processes. Unfortunately, some customers are not really concerned with productivity because they can’t create haul fleet efficiency and so focus on fuel efficiency only.
The author is large excavator product specialist, Caterpillar.
Power Management Modes
Cat excavators are able to operate in a choice of power management modes:
- High Horsepower (HHP) – Capability to operate at maximum rpm and reach 100% hydraulic flow depending on the application.
- Standard Power (SP) – Reduces maximum engine revs and reduces maximum hydraulic pump flow.
- Economy (Eco) – Further reduction in maximum engine rpm and maximum hydraulic pump flow rate.