James Morgan travels to Caterpillar’s Malaga Demonstration & Learning Center in Spain to get to grips with the 320D2; a hydraulic excavator that has been built to deal with demanding operating conditions on Saudi Arabian construction sites
When it comes to GCC construction markets, few come close to that of Saudi Arabia. In 2013, construction projects worth a total of $42bn were awarded across the Kingdom, compared to $17bn during the previous year.
What’s more, with a raft of unprecedented initiatives underway – such as Kingdom Tower, King Abdullah Economic City (KAEC), and the Riyadh Metro – this rapid pace seems set to continue for years to come.
As well as spelling good news for the country and its citizens, this growth is music to the ears of the region’s PMV community.
However, delivering equipment that’s tough enough for typical operating conditions in Saudi Arabia is anything but simple. If a piece of kit is to survive in this unforgiving environment, it must be able to cope with heat, humidity, dust, and some of the dirtiest diesel in the Middle East.
Impressive though they may be, the precision, computerised machines common across regulated regions simply don’t have what it takes to make it on the construction sites of Saudi Arabia.
With this in mind, Caterpillar – in conjunction with its authorised KSA distributor, Zahid Tractor – has developed the 320D2; a back-to-basics hydraulic excavator designed to meet the demanding requirements of KSA contractors.
Feedback provided by Saudi Arabian end users was instrumental in the development of Caterpillar’s 320D2; the successor to the popular 320D hydraulic excavator. In conjunction with Zahid Tractor, Caterpillar surveyed its KSA customers to find out what they liked about the 320D, and what they thought could be improved.
Users responded in unison; whilst they were satisfied with the excavator’s performance and durability, they wanted a product that offered lower operating costs and that was able to cope with low-quality diesel common across the Kingdom.
“On average, fuel in the Middle East is around five times dirtier than it is in Europe,” explained Alexandre Favero, Caterpillar’s product application specialist for hydraulic tracked excavators in Africa and the Middle East.
“Users emphasised how important it was for us to consider this fact and to test our engines before sending them to market. Customers also said that electronic injection systems are too sensitive for contaminated fuel. This message was especially clear from those contractors who preferred to repair their own engines. Finally, we were told that operating costs were too high,” he said.
Whilst fuel consumption certainly impacts operating costs for Saudi users, due to the low price of diesel in the Kingdom, it is by no means the most important factor. A more pressing concern is the cost associated with repairs and maintenance; KSA customers want components that are more reliable, and that can be replaced over longer time intervals.
This feedback informed Caterpillar engineers about the elements of the 320D that should be retained, and those that should be rethought. Their first course of action was to take a back-to-basics approach to the engine, moving from an electrical to a mechanical-based model.
First and foremost, by making maintenance easier and cheaper, this step was intended to facilitate operators who prefer to adopt a DIY approach to machine repair. However, it also allowed the Caterpillar team to reduce pressure.
“The 320D had a maximum pressure of 1,200 bar, but for the 320D2, it is just 200 bar, making it much more tolerant against contaminants,” said Favero.
At high pressures, fuel contaminants can cause significant damage to the internal components of a machine. Since such contaminants are so common in Saudi Arabia, the low-pressure 320D2 offers greater protection against system failure.
“At a pressure of 1,200 bar, a single micron particle in the fuel can be travelling as fast as a bullet when it makes contact with a component,” explained Khalid El Shurafa, marketing manager at Zahid Tractor.
“This can cause parts of the machine to chip away, which in turn, can lead to additional contaminants in the fuel. When pressure is high, one micron can create more particles as it continues on its journey through the system. However, with the 320D2’s mechanical engine, the pressure has been reduced significantly, and this will help to minimise problems associated with fuel quality and contaminants,” he added.
Despite the advantages that the Cat C7.1 mechanical engine offers to KSA customers, the engineers were forced to make certain compromises. A 320D fitted with a C6.4 engine, for example, produces net power of 103kW at 1,800 rpm. The 320D2’s mechanical replacement, meanwhile, offers 98kW at 1,700 rpm.
On the face of it, this might look like a step backwards, but as Favero explained, the impact on performance is minimal and there are actually some significant advantages to the updated configuration.
“You can see that the machine’s net power has fallen, but we are not making a car,” he observed.
“More important than the machine’s power is the hydraulic power, which we were able to maintain. Moreover, the 320D2 is able to achieve this level of performance at 1,700 rpm rather than 1,800 rpm.
“One might assume that a machine operating at lower rpm is a machine that isn’t performing as well, but this just isn’t the case. It’s actually a machine that will enjoy a longer life,” Favero explained.
In order to maintain the 320D2’s hydraulic power, the Caterpillar team focused on optimising pump efficiency. By introducing shrouds, they decreased the space between the pumps and their casings, therefore minimising turbulence created by the system’s spinning components.
In doing so, the manufacturer increased pump efficiency by 3.7kW, reducing fuel consumption in the process.
“Although we have moved back to a mechanical engine, we’ve been able to decrease fuel consumption by 3%,” revealed Favero.
“And don’t forget, Caterpillar is very conservative when it comes to such figures. Personally, I think that if you were to visit an operator in Saudi Arabia who has been using one of these machines, he would tell you that the fuel savings are much greater than 3%,” he added.
Another major focus during the development of the 320D2 was its filters. The 320D required three or four filters, depending on the model in question. As these components needed to be replaced at intervals of approximately 250 hours, this could be a costly affair over time.
Replacing all four filters on a 320D with a Cat C6.6 engine, for example, would cost $4,404 in parts and labour. The 320D2, on the other hand, requires just two filters, and the change interval has been extended to 500 hours. Replacing the latest filters costs just $1,410, offering significant savings for operators.
The influence that Saudi Arabian end users have had on the 320D2 is also evident when looking at the type of components with which the excavator is compatible. For example, a large proportion of 20-tonne excavators operating in the Kingdom are used for hammer applications; a vital, but dirty, job. Caterpillar and Zahid have catered to this demand with the hammer return filter.
“More than 80% of 320D units operating in Saudi Arabia are used for hammer applications,” El Shurafa explained.
“Hammer work is not clean; it can introduce lots of contaminants into a machine’s hydraulics system, so having a filter to clean the hydraulic oil that flows back from the hammer is vital. Operating without an appropriate filter will lead to a damaged hydraulics system,” he said.
Favero continued: “The 320D had a return filter, but it was designed specifically for bucket applications. This type of filter will quickly become clogged if used during hammering. The 320D2’s hammer return filter, however, bypasses the main valve, reducing the amount of back pressure that is created. In turn, the oil is cooled by the hydraulic cooler, and the durability of the pump’s components is improved.”
The 320D2 boasts an impressive array of KSA-inspired improvements, but Caterpillar has also been careful to play to its strengths. In order to ensure that users’ end costs are minimised, the manufacturer has left several sections of the 320D2 as they were on the previous model.
“The front section of the excavator remains untouched, and the undercarriage is identical to that of the 320D,” said Favero.
The 320D2 is a rare breed in today’s technology-driven PMV market. Rather than adding features for their own sake, Caterpillar has designed a product perfectly in tune with the needs of Saudi Arabian end users. In many ways, this isn’t a model built by Cat; it’s a machine crafted by the Kingdom.
Test Drive:
Caterpillar 320D2 L Hydraulic Excavator
James Morgan climbs aboard the 320D2 L hydraulic excavator to find out whether the Saudi Arabia-inspired Caterpillar manages to deliver on its manufacturer’s promises
The beauty of Caterpillar’s Malaga Demonstration & Learning Center is that it provides visitors with the opportunity to engage in the practical as well as the theoretical. Located on the Costa del Sol in southern Spain, the facility boasts an array of conference rooms, a 200-seat auditorium, and wide-open terrain ripe for excavation.
The model available at the demonstration event was Caterpillar’s 320D2 L hydraulic excavator; a version that sports a longer chassis to aid stability on uneven and rocky terrain. Not wanting to miss the chance to do a little extra digging, I climbed aboard to sink the machine’s teeth into the Spanish soil.
Although the excavator’s redesigned mechanical engine is slightly less powerful than the electrical equivalents of its predecessor, you’d be hard pushed to notice. The 320D2 L felt both powerful and responsive.
The movement of the machine was anything but sluggish, and the boom never appeared to strain when slicing through the terrain. Within no time at all, I was removing bucket loads of dirt from the ground, and the only encumbering factor was my own limited skill as an operator.
The lines of sight to the front and sides are generous, and the excavator’s controls are just as tight as you’d expect from a Caterpillar machine. If anything, I found the 320D2 L to be a little too responsive, but this is nothing that couldn’t be overcome with practice – and of course – a more experienced operator at the helm.
It’s important to remember that improved performance was not at the top of the engineers’ to-do list when designing the 320D2. Caterpillar can be said to have achieved its customer-led objectives if it succeeds in delivering increased reliability and lower operating costs whilst maintaining performance levels offered by the 320D.
One thing that I cannot attest to is the 320D2’s ability to cope under KSA working conditions. The Malaga sun was certainly warm, but temperatures were nowhere near those reached during the height of a Saudi Arabian summer.
Even so, Zahid Tractor has undertaken a comprehensive testing regime to ensure that the 320D2 is tough enough to stand the test of time on its new stomping ground.
“We sent machines to very harsh customer sites across the Kingdom to monitor their performance in extreme conditions,” explained El Shurafa.
“The models were used for a variety of applications and we even added a few to our rental fleet. Before we launched the excavator, we had to be 100% confident about its ability to cope with operating conditions in Saudi Arabia,” he told PMV.
