There are specific types of excavator machines that are suitable for the particular demand of a project. Among them are crawler and wheeled machines. But which one is right for you? After all, using the wrong excavator can heavily affect the efficiency, cost and safety of the construction, mining, or any infrastructure development project.
Thus, in this blog, you will know all about the difference between wheeled and crawler excavators. As well as what kind of advantages each excavator machine brings, and which is the right machine, depending on the type of project you are handling.
What is a Crawler Excavator Machine and Its Advantages?
This type of excavator is known to be a heavy-duty machine due to its capability of powerful digging force and excellent stability on challenging terrain. They are easily recognisable thanks to them having continuous tank-like tracks made of metal or rubber tracks spanning the length of their chassis. They are the most common types of excavator machines seen on large construction sites. Offering excellent stability, but at the expense of slow top speed, which is typically less than 8–10 km/h.
On the other hand, they have pretty low ground pressure thanks to the distribution of their weight over a wider area. Plus, they come in different sizes, like a mini excavator under 6 metric tons, up to a massive excavator weighing over 40 metric tons. Such versatility and power, combined with a long track, provide unshakable stability. This ensures that heavier loads are handled safely, as well as using their greater breakout force for tough digging, trenching, and rock hammering.
Furthermore, their crawler-like long tracks enable them to have excellent grip on the mud, loose soil, sand, steep slopes, rocky ground, and uneven construction sites. This makes crawler excavators to be highly versatile in sites with poor ground conditions. As mentioned before, their lower ground pressure helps them to work better on soft ground, thus minimising site damage and reducing the risk of sinking. Such advantages make them a continuous working machine, reducing unnecessary operation holdups for projects in fixed areas.
What Disadvantages Can You Expect?
As mentioned before, all that force and stability come at the cost of speed. The crawler excavator machine can be very slow, making it very hard to move from one site to another. This slow movement speed can be both time-consuming and inefficient. Furthermore, they can not move between non-adjacent job sites or over long distances on their own. They need a lowboy trailer or something similar to its size to transport the excavator to the place required, adding to both cost and time.
The metal tracks of crawler excavators are rigid enough to seriously damage paved paths made of asphalt or concrete without a protective mat. Moreover, the excavators damage the road enough to make it unsuitable for roadwork and a hassle for transportation. Their undercarriage is complex and subject to high wear and tear from abrasion and debris, leading to higher maintenance costs and downtime. But apart from knowing the advantages and disadvantages of crawler machines, which projects are suitable for them?
Which Projects are Ideal for a Crawler Excavator Machine?
You already at this point know that crawler machines are best for large-scale projects like the construction of foundations, basements, and general site development. But, they are also good for earthmoving and trenching works, which involve digging pipelines, trenches and large-scale excavations. That’s not all, they are also favoured for mining and quarrying in rough, rocky terrain where handling of heavy loads is necessary.
The crawlers are also helpful in forestry and land-cleaning projects. Where operations may be carried out on uneven, often muddy or sloping ground, which requires the stability only offered by a crawler excavation machine. Lastly, they are also ideal for demolition, where maximum stability combined with high force is needed. They can handle heavy debris and other necessary attachments like grapples or hydraulic hammers with ease.
What is a Wheeled Excavator Machine and What Advantages Does it Bring?
A wheeled excavator or also known as a rubber-tired excavator machine, as the name suggests, swaps tracks with heavy-duty rubber tyres. Unlike crawlers, these tyres make wheeled excavators highly mobile. Such versatility makes them more suitable for projects that are situated in urban locations and require frequent relocation of the machines from one project site to another. Their heavy-duty rubber tyres help them to attain high speeds, often able to travel up to 32–40 km/h on public roads.
Moreover, higher mobility does not mean that they are highly unstable. Though they may not be as stable as crawler excavators, a wheeled excavator machine relies on outriggers or a dozer blade deployed on-site for stabilisation during digging. These blades also help with backfilling and levelling. However, they do have high ground pressure due to the smaller contact area of the tyres. They also have different steering modes due to having a steering wheel.
Wheeled excavators are great for saving time and resources as they can often use public roads for travelling from site to site. Many contractors favour these machines for their great mobility and for saving transport costs. Apart from that, they also cause no harm to paved roads, asphalt, finished concrete, and manicured lawns, unlike the crawlers. This makes them the perfect choice for any projects set in urban areas.
Also, unlike the crawler excavators, a wheeled excavator machine does not need any extra transport trailer. This massively reduces the extra cost of overhead and logistics of excavators for short or long distances. Additionally, the wheel and axle systems are generally less complicated to maintain, which leads to lower repair expenses as well. But, not everything is sunshine and roses with wheeled excavators. Let’s look at some of their disadvantages.
Disadvantages You Will Run into with Wheeled Excavators
In comparison to a crawler excavator machine, wheeled excavators have much lower digging force and stability, even when deployed with outriggers. They are also not ideal for heavy lifting and aggressive digging tasks, as too much force can compromise their balance. On the other hand, their tires are great for well-paved roads, but they perform poorly on soft, muddy, sandy, or extremely uneven terrain. Such terrain causes them to get stuck in muddy places, jeopardising the entire operation.
They also cannot attain stabilisation on their own, as they require setting up and retracting outriggers or the dozer blade for every digging operation. Such systems add to the cost and time of setting up proper operation for each new location. As mentioned before, due to having higher ground pressure, wheeled excavators run into the problem of sinking into soft ground or the tyres causing rutting.
Which Projects are Ideal for a Wheeled Excavator Machine?
Wheeled excavators are made for tight city spaces, road repairs, and street maintenance, where little to no disruption to daily life is permitted. It is ideal for road infrastructure projects like ditch cleaning or placing barriers, etc. Furthermore, they are ideal for projects on large, established sites with a mix of paved and gravel roads, where the machine needs to travel frequently over distances. They are also used in recycling yards or industrial plants where high manoeuvrability is necessary.
Final Takeaway
It all boils down to the type of excavation work you carry out. If you are someone who needs extra force and stability, especially on rough and uneven terrain, then a crawler excavator machine is the way to go. But, if most of your construction projects are situated in an urban setting, where high mobility in tight spaces and relocation is mandatory, then a wheeled excavator is your right bet.
