Plant Machinery

Posts Tagged ‘Loaders’

Articulated front end loaders are designed by engineers from the ground up to push hard into earth and lift heavy loads at the front of the loader and also to be extremely versatile in the field.

The following article illustrates 8 points of difference between an articulated front end loader and a front end loader fitted to a tractor generally after purchase.

1. Maneuverability. Articulated front end loaders allow you to work in very tight areas – places where tractors can’t even begin to access. Articulated steering is similar to having two very short machines attached together with a rod, so really you are operating a very short machine and the other chassis follows behind. Tractors on the other hand have a rigid chassis and are no-where near as maneuverable as a modern articulated front end loader. This ability to operate in confined areas of articulated front end loaders allows you to gain access to places you couldn’t with your tractor. The higher utilization rate of articulated front end loaders pays off with less jobs having to be performed manually. Often maintenance that has been done for years by hand, now gets done rapidly with a compact articulated front end loader! The much better all around visibility in a compact articulated front end loader also makes productivity in confined areas much higher as the operator isn’t concerned about damage to buildings, machinery, personnel or animals constantly on the job site.

2. Steering under load. Articulated front end loaders utilize strong rams to pivot the whole front chassis which steers the vehicle in the required direction. The powerful steering is required as under load the centre of gravity shifts approximately 2/3 of the whole machine onto the front axle, making it heavy under load if the steering isn’t suitable. Tractors however are designed to tow – this is the reason the big wheels designed for heavy loads, are mounted at the back and the small wheels, which are easier to steer, are mounted at the front. When a front end loader is added to a tractor and the operator loads the bucket, the tractor’s centre of gravity shifts onto the front wheels and axles, making it very hard to steer as they aren’t designed to turn under such a heavy load. As the centre of gravity shifts when a load is picked up with the front end loader a massive amount of pressure transfers onto the front axle and CV joints in the tractor. Tractors really are designed to tow and when loaded on the back of the three point linkage when towing, pressure is actually reduced on the front wheels as the centre of gravity shifts backwards taking pressure off the CV joints! Tractor front axles aren’t designed for the constant loading when working with a front end loader and may not last. Front wheel assist has now been included by some tractor manufactures to help with the steering when the front end loader takes a full load but it still has difficultly under full load as the CV joints are loaded up and under stress. Articulated front end loaders however have rigid axles so they don’t have any CV joints to get damaged under when the centre of gravity shifts forwards when loading – the steering is controlled via articulating the whole front chassis – just another reason showing that articulated front end loaders are truly designed from the ground up for loading, particularly in the long run when maintenance costs are taken into account.

3. Loading speed. Many farmers load their trucks with tractors, however when you load with a big tractor you waste a lot of diesel compared to an articulated front end loader. When operating a big tractor you need a lot more space to get in the right position to load and then to dump into the truck. The truck must be parked much further away from the pile of material to be moved as the tractor has limited maneuverability.

On the other hand articulated front end loaders operate easily in very confined areas so they don’t need to travel as far to dump and get in the right position to load again. This is due to the very tight steering angle – one of the greatest advantages of an articulated vehicle. The most efficient compact articulated front end loaders on the market now have articulation angles of 47 degrees. Smaller articulated front end loaders, generally under 1750kg, have articulation angles of 60 degrees as they don’t incorporate a drive shaft so the articulation angle can be made much higher.

4. Transmission advantages. Most modern articulated front end loaders utilize a clutchless hydrostatic transmission which gives you smooth power transfer when digging constantly into soil or hard materials. The hydrostatic transmission makes articulated front end loaders much faster in speed than tractors in loading situations, allowing the operator to perform more work in less time. As articulated front end loaders use a fluid hydrostatic the operator isn’t wearing out mechanical clutches or gearboxes with friction as you would need to constantly shift between gears with a manual gearbox like in a tractor.

The hydrostatic transmission that is used in the most modern articulated front end loaders allows the driver to concentrate solely on loading the bucket rather than having to change manual gears all the time to maximize speed against the torque required for loading. The hydrostatic transmission means that the articulated front end loader can be driven into a pile for loading and the hydrostatic pump is load sensing and automatically senses the power required and adjusts torque as necessary for the most efficient loading. The speed in the hydrostatic articulated front end loader is controlled just by pressing the accelerator pedal down more or less, the same as operating an automatic car.

5. Low operating height. Some modern compact articulated front end loaders are built with very low operating heights. This allows you to go inside buildings and perform more work. Tractors are designed for towing with large rear wheels and so are much higher and could never access such low areas. This allows many intensive farming operations such as small horse stables, cow sheds, chicken pens and greenhouses to be quickly cleaned out. Compact articulated front end loaders are also generally much narrower than equivalent tractors and allow access up the side of residential properties, building sites, and vineyards. A big advantage of compact articulated loaders is that the low height and narrow width allow access into building and demolition sites for construction and removal of debris.

The low height and relatively narrow width of articulated front end loaders when further coupled with the extremely tight turning circle gives even more accessibility in confined spaces. The low operating height of a compact articulated front end loader also gives another benefit not realized at the beginning – the easy access for personnel to the cabin area means they get used constantly for all jobs as they are so convenient. Tractors, due to their high wheels at the back must have high cabin heights and constantly getting in and out can be chore, particularly for smaller tasks and where one has to get in and out of the cabin frequently and so often the job is just done by hand. Another advantage of the low height of compact articulated front end loaders is when trucking machines about the total transport height is lower and permits don’t need to be obtained.

6. Centre of gravity. Articulated front end loaders are built from the ground up to maximize the efficiency of the weight they can lift at the front of the machine. The placement of counterweights and the longitudinal centre of gravity on an articulated front end loader is designed completely differently to that a tractor. Articulated front end loaders have a very heavy chassis and the most efficient designs incorporate weight as far behind the rear axle as possible to make lifting at the front as efficient. Significant weight as far out the back of the rear axle as practical makes it possible to lift higher amounts at the front of the articulated front end loader due to the simple lever principle – the more counter weight out the back, the more effective it will be. Articulated front end loaders when unloaded have approximately 2/3 of the total machine weight resting on the rear axle, however when loaded the centre of gravity shifts to 2/3 of the total weight on the front axle.

Tractors on the other hand are built completely differently to an articulated front end loader – all their weight is mounted as far forward as possible to give the best stability and capacity when towing – counterweights are even designed to hang off the front of the tractor! Their longitudinal centre of gravity of a tractor is approximately 50/50 on the front and rear axles, with a shift towards more weight on the front axle in bigger tractors. A quick look at any tractor shows that the engine has been mounted as far forward as practical which gives great stability at the back of the machine and allows the tractor to maintain weight on the front wheels for traction when towing a heavy object – the opposite of an articulated front end loader.

7. View of front end when operating. Compact articulated front end loaders are built from scratch to have a great view of the front end as this is where all the work occurs and the driver must have a great view if they are to perform work quickly and safely. The front chassis on an articulated front end loader is minimized in size so maximum visibility is created for the driver. The mast is also designed to be as streamlined as possible so no interference occurs to the drivers view and anything unnecessary is put behind or underneath the driver such as the engine.

The view of the front end of a tractor is totally different – tractors are designed for towing so the engine is put as far forward as possible and then a front end loader mast added afterwards. The tractors engine totally obscures the front end of the tractor so it is very difficult to see the working face and more guess work and less precise work has to be performed with a tractor than an articulated loader. The tractor is thus can only be used for very rough work and all finishing must be performed by another machine or done later by hand. It is very easy to see which machine is built for heavy duty work – an articulated front end loader or a tractor with a loader, pay careful attention to the size of rams, pins and the strength of the mast and it is quickly apparent that only a good quality articulated front end loader is built for an industrial life.

8. Towing Vs pushing. Articulated front end loaders are built for constant pushing. However, tractors are designed for towing; they are not designed to develop the pushing force which is needed for loading and shifting. Generally everyone understands that the bigger the wheel, the less the torque that can efficiently generated from it. The massive rear wheels of big towing tractors make the ability of developing a lot of torque an impossibility, however big tyres at the back create a lot of stability and the ability to have massive loads on the rear utilizing the three point linkage perfectly. The front wheels on tractors however are very small and not designed for the same loading as the rear – hence their small size. Articulated front end loaders however have the same tyre size all around which are much smaller than tractors so it is easy for the axles to generate much higher torque which is required to dig into hard materials when loading or cutting into bare earth.

When you think of construction equipment loaders are what normally cometo mind. Loaders are considered tractors with the bucket on the front of the tractor and the engine on the back as a counter weight for the work. Unlike excavators most loaders use wheels rather than tracks. The types of loaders and uses are listed below.

Front end Loader: This type of loader is also called a bucket loader or scoop loader because it has a wide square bucket that tilts to capture the dirt or to dig out an area. The bucker is a removable attachmentso you can also use it as a forklift.

You can also use a clamshelltype of bucket that opens to grab whatever you are working on in its jaws.

Loaders are used for snow removal, dirt removal, farming, andconstruction sites.

Skid and Track Loaders: A skid loader is a smaller loader than theaforementioned equipment. Skid loaders use 4 wheels rather than tracks, but they are similar to the mini excavator in design with a hydrauliclift and bucket on the front of the equipment. The difference is where the life arms are positioned. They are behind the driver’s shoulders rather than more forward of the cab.

Backhoe Loader: This type of loader combines two pieces of equipment into one. First off you have the traditional loader with the front-end bucket and the rear of the tractor has a backhoe. Inside the seat swivels so the operate can see what he or she is doing when operating the backhoe portion. When using the backhoe there are hydraulic stabilizers the operator will place on the ground in order to lift it off the ground a bit.

Loaders are very similar to excavators, but they each have their own uses. Most loaders are for the removal of debris or lifting rather than digging.

Construction is a multitasking activity. There are several people who are behind the job coming from the architectural and engineering fields. Normally, it is the project engineer who manages the work with several supervisors like the construction engineer, design engineer, etc. But for every successful venture comes with a careful planning. And those directly in charge with the overall design and execution are the ones who should know that the Caterpillar equipment is an infrastructure need.

A Heavy Need

For huge projects, heavy equipment are needed for the construction activities. There are three general types of infrastructure project that would definitely need front end loaders, and they are:
1. Building Construction. This is the common type where you will see from the smallest renovation of one room to as big as constructing a new building itself as an additional structure to a real property.
2. Highway Construction. You will find these projects in growing or expanding communities. With the help of front end loaders, the process of constructing the infrastructure in existing environment hastens.
3. Industrial Construction. This type of infrastructure is usually made by owners of big companies or corporations like medicine, manufacturing, petroleum, etc. The processes of work are handled by experts who likewise need powerful machines like Caterpillar equipment.

The Caterpillar Type

Caterpillar equipment are machines that are usually used extensively for the development of infrastructure projects. Aside from its use in the construction, Caterpillar equipment is also utilized in the maintenance of the various projects of the construction industry. From the Caterpillar type of equipment, other machines are incorporated with it like excavators, dozers, backhoes and loaders. Thus, we have the Caterpillar front end loaders.

The Loaders Advantage

Loaders or the front end loaders are wheeled machines that employ a tilting bucket and movable arms for easy lifting and moving of construction materials. Most often, depending on the work being done at the time it is needed, the tilting bucket may be replaced by other devices. Forks or clamshells are the most common replacement. Loaders can also be classified depending on the nature of the work, the size or scope that it has to perform.
? Skip Loader
? Skid Steer
? Backhoe
? Telescopic
? Wheel
? Scraper

A Significant Use

In the different construction of infrastructures, the front end loaders have their share of importance. Here are some of the uses of the machine:
1. For building roads, highways, and airports.
2. For the construction of water, dams, and sewer systems.
3. For the construction of the different housing projects, commercial buildings, schools, office, and hospital buildings.
4. For the mining industry, it is especially useful in drilling.
5. For excavation, minor demolitions, digging, preparation of constructions sites.
6. For simple landscaping.

Caterpillar front end loaders are the contractors’ best asset. They answer to the multitasking needs of the construction business.

Below broad definitions of various loader types are outlined.

Some of these definitions are interchangeable and often just relate to the size loader you are talking about. For example “articulated loader” is the generic term for any articulated loader and can include – mini loader, mini digger, front end loader, wheel loader and can even include some backhoe loaders which are articulated.

ARTICULATED LOADER
An articulated loader has an articulation joint in the middle. The loader is made from two chassis joined together, as opposed to a rigid bodied machine, like a car or skid steer. An articulated loader by definition has articulated steering, and covers all loaders with articulated steering from articulated mini loaders weighing in at just 1500kg, to the world’s largest wheel loaders.

Articulated loaders have a lot of benefits compared to rigid bodied machines and any operator will quickly tell you this.

MINI LOADER and MINI DIGGERS
A mini loader is generally classified as a loader with a weight under 2000kg. The smallest mini loaders are stand on skid steer type loaders, although relatively recently some companies have released stand on mini articulated loaders. The stand on mini loaders are very limited in terms of capacity and size, as operators aren’t given a high comfort level as they have to stand up all day which isn’t conducive to a productive work life. The mini stand on loaders are suited to small jobs requiring the operator to jump on and off frequently.

The next step up in mini skid steer loaders are mini “bobcat” style loaders which have a seated operating position. These mini skid steers allow the operator to perform tight access work, and the comfort level increases as at least the operator has a seat to sit on throughout the day.

The biggest recent trend however is towards articulated mini loaders which are now rapidly becoming commonplace on construction sites across the world. They have a seat to operate from , great all round visibility as the operator sits on top of the machine and are able to handle more weight as the wheel base is significantly longer than a mini skid steer. An articulated loader of the same weight can outperform a mini skid steer in lift capacity as a longer wheel base gives more leverage at the tool frame.

The articulated mini loaders are also very comfortable to drive if an oscillating articulation joint is incorporated between the two chassis. The oscillating articulation joint allows the loaders wheels to conform to the rough terrain so each bump isn’t going through to the operator’s seat, basically it acts a type of suspension. Articulated mini loaders are now highly maneuverable so give the advantages of a longer wheel base, but are still able to work in restrictive areas, the same as a mini skid steer. The articulated mini loader also has the massive advantage of low ground disturbance and very minimal tyre wear.

Being able to run as many tools as possible is critical with any mini loader and hence all mini loaders – either articulated or skid steer, will have auxiliary output as standard. to be able to run tools.

FRONT END LOADER
The term front end loader can refer to any loader with a bucket attached at the front. However it is just about always referred to as an articulated loader and not a skid steer as front end loaders were traditionally used for the heavy duty front end work. The mast of a front end loader is fixed horizontally, as opposed to a telescopic loader, which can “telescope” out to gain more reach (described below). An articulated mini-loader, articulated loader and wheel loader are all a type of front end loader. What weight class actually contributes a front end loader category is quite arbitrary, but some manufacturers will designate articulated loaders in the operating weight 2 tonnes to 5 tonnes as front end loaders, however any size machine can often be called a front end loader.

The term front end loader is also used for tractor style front end loaders. These are a separate mast and bucket attached to the front end of a tractor, often after purchase, to enable it to do some work at the front of the machine. Tractors however are built for towing as the main weight of the machine, the engine, is placed far forward to give traction when towing and so is not ideal for heavy duty front end loader work.

All articulated front end loaders, articulated wheel loaders and all articulated mini loaders built by major manufactures have the seating position mounted on the rear chassis section. This is important as it allows much greater performance to be achieved quickly by the operator. When the operator sits on the rear of the loader, reversing is the same as when reversing a car, however when you sit on the front of the loader – every time you need to reverse the loader it is like having a swinging trailer behind you. Most operators’ can eventually get used to this operating position, but having to think every time when reversing hinders productivity, even with very experienced operators. This is particularly noticeable when working in confined areas as the tail swings out when attempting to reverse and must be controlled. This is the reason that all major world manufacturers now make the operator sit at the rear of the machine.

WHEEL LOADER
A wheel loader is generally regarded as a large articulated loader, however one of Australia’s industry bibles – Earthmover and Civil Contractor Plant Spec’s classifies all articulated loaders as wheel loaders and further categorizes them by operating horsepower. It is only articulated steering that gives the ability for such a large machine to operate efficiently, particularly over around the 8 tonne mark. Wheel loaders are often regarded as articulated loaders over 5 tonnes and continue up to the largest loaders in the word which are over 200 tonnes.
The larger the wheel loader, the greater the tendency for the loader to become a dedicated machine and not have a quick attach too frame. This is because wheel loaders are often used for production and so versatility is not required. Purpose built loaders can often be more efficient for a single job than a general purpose machine, by bringing in the hitch closer to the front axle of the loader, so capacity and stability is maximized.

FRONT AXLE STEERED LOADER
Front axle steered loaders are rigid bodied loaders, with the same steering principle as a car, the front wheels turn to steer the loader. This group covers the backhoe loaders, as explained below and all tractors. Tractors, although they can be fitted with a front end loader attachment to do light duty work, aren’t designed from the ground up for industrial earthmoving but are instead designed for towing as they have the majority of their weight mounted far forward so weight is still maintained on the front wheels when towing heavy implements.

BACKHOE LOADER
Backhoe loader’s are a front end loader with a permanently mounted backhoe, which is an excavator arm designed for trenching. Most manufacturers offer backhoes as a rigid bodied loader for extra stability when trenching, however a couple of articulated backhoe’s do exist. Backhoes in recent years have fallen out of favour as the purpose build excavator will always outperform them on a job site. The backhoe is also a compromise as a front end loader as an articulated loader will always outperform a rigid bodied loader due to the advantages of articulated steering.
A new entry into this backhoe market that crosses some traditional boundaries is the release of the front mounted excavator hoe. This allows the front end loader operator to add a front mounted hoe to perform some excavation work. The performance isn’t the same as a purpose built excavator, but allows extra utilization on a job site and doesn’t require trucking a new machine in just to finish off routine excavation tasks. The front hoe is particularly suited to articulated loaders as the operator needs to just turn the steering wheel slightly to dump the load out of the front hoe, and then to turn back again to start excavating again. Skid steers on the other hand start to scrub a lot of earth out from under the skid steer wheels when turning on the spot to dump after excavating a scoop of earth.

TELESCOPIC LOADER
A front end loader has a fixed mast – the mast can’t extend horizontally, only up and down. A telescopic loader on the other hand can extend out horizontally. The extra reach of a telescopic loader can be advantageous in certain situations but must be used with caution as the further the mast is extended, the lower the capacity if the loader as the centre of gravity shifts out. For true earthmoving work or materials handling with a bucket, an articulated loader or one of the modern articulated telescopic loaders is always the machine of choice due to superior all round visibility compared to rigid bodied telehandlers.

SKIDSTEER
A skidsteer is a rigid bodied (single chassis) loader, designed to skid on their wheels or tracks to turn sharply, and can even turn on the spot if necessary. Articulated front end loaders on the other hand use the articulation joint between the front and rear chassis to steer the loader in the required direction, so they cannot turn on the spot. Modern articulated loader manufacturers now make articulated loaders highly manoeverable and give numerous benefits over skidsteers so give the extra benefit of low tyre wear in comparison to a skidsteer. For a skidsteer to turn so sharply, one side of wheels/tracks locks up allowing the wheels on the other side to skid on themselves, allowing a very sharp turn. The downside here is that the tyres may be worn out very quickly as a result. The ground also gets ripped apart, often doing a lot of damage to the surface, even on asphalt. Visibility is also quite bad, as the driver is confined in a small metal cabin with the mast attached either side of the cabin, further restricting visibility. The driver sits very low to the ground with the engine behind the operator.

Skidsteers are broken up into two main groups – stand on skid steers, and larger skid steers. All sizes of skid steers are available with conventional tyres or with tracks. Tracks give more grip in boggy conditions, however maintenance costs are incredibly high compared to wheeled skidsteers. The cost isn’t just the tracks themselves, but also the complex lug and wheel assembly that turn the tracks. Fuel consumption is also significantly higher in a tracked loader as the rolling resistance of a track is much higher than wheels.

FORKLIFT
A forklift is an industrial vehicle with a hydraulically operated vertical mast and pallet forks. Forklifts are a common sight in warehouses worldwide and generally don’t have the capability to operate off hard surfaces unless they are specifically built for an all terrain capability. The pallet forks or tines are inserted under loads to lift, stack and move them. Typically a forklift is not designed to have many other tools or attachments.

Forklifts are purpose built and are able to lift larger loads that a comparable front end loader with a fork attachment. The vertical mast of the forklift is mounted much closer to the chassis of the machine, so the centre of gravity of the load is closer which allows the forklift to always outperform a front end loader of comparable weight. Some operators however still prefer to use a front end loader as the extra reach allows them to unload a truck from one side. A new entry into this market is the Schaffer articulated forklift, it combines the all terrain capability of a strong earthmoving front end loader with the capacity of an industrial forklift.